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SIM900_AT Command
Manual_ V1.03

SIM900 AT Command Manual
SIM900_AT Command Manual_V1.03 2 12/24/2010
Document Title: SIM900 AT Command Manual
Version: 1.03
Date: 2010-12-24
Status: Release
Document Control ID: SIM900_AT Command Manual_V1.03
General Notes
SIMCom offers this information as a service to its customers, to support application and
engineering efforts that use the products designed by SIMCom. The information provided is based
upon requirements specifically provided to SIMCom by the customers. SIMCom has not
undertaken any independent search for additional relevant information, including any information
that may be in the customer’s possession. Furthermore, system validation of this product designed
by SIMCom within a larger electronic system remains the responsibility of the customer or the
customer’s system integrator. All specifications supplied herein are subject to change.
Copyright
This document contains proprietary technical information which is the property of Shanghai
SIMCom Wireless Solutions Ltd, copying of this document and giving it to others and the using or
communication of the contents thereof, are forbidden without express authority. Offenders are
liable to the payment of damages. All rights reserved in the event of grant of a patent or the
registration of a utility model or design. All specification supplied herein are subject to change
without notice at any time.
Copyright © Shanghai SIMCom Wireless Solutions Ltd. 2010

Version History
Version Chapter What is new
V1.00 New version Created on the basis of SIM900 AT Test Result
V1.01 3.2.50 AT+CALS
6.2.27 AT+CBTE
6.2.30 AT+STTONE
8.2.21 AT+CIPDPDP
8.2.25AT+CIPUDPMODE
6.2.45 AT+SGPIO
6.2.46 AT+SPWM
6.2.47 AT+ECHO
Add new command
Add new command
Add new command
Add new command
Add new command
Add new command
Add new command
Add new command
V1.02 3.2.16 AT+CLCC
3.2.30 AT+CR
Add write command
Add parameter GPRS
V1.03 6.2.47 AT+SPWM
6.2.48 AT+ECHO
6.2.50 AT+GSMBUSY
8.2.26 AT+CIPRXGET
8.2.27 AT+CIPQRCLOSE
8.2.28 AT+CIPSCONT
9.2.1 AT+SAPBR
10.2.x HTTP commands
11.2.x FTP commands
Modified the command
Modified the parameter scope
Add new command
Add new command
Add new command
Add new command
Add new command
Add new commands
Add new commands

Contents
1 Introduction..................................................................................................................................11
1.1 Scope of the document..........................................................................................................11
1.2 Related documents ................................................................................................................11
1.3 Conventions and abbreviations .............................................................................................12
1.4 AT Command syntax.............................................................................................................12
1.4.1 Basic syntax ...................................................................................................................12
1.4.2 S Parameter syntax.........................................................................................................13
1.4.3 Extended Syntax.............................................................................................................13
1.4.4 Combining AT commands on the same Command line.................................................13
1.4.5 Entering successive AT commands on separate lines.....................................................13
1.5 Supported character sets........................................................................................................13
1.6 Flow control..........................................................................................................................14
1.6.1 Software flow control (XON/XOFF flow control).........................................................14
1.6.2 Hardware flow control (RTS/CTS flow control)............................................................15
2 AT Commands According to V.25TER.......................................................................................16
2.1 Overview of AT Commands According to V.25TER ............................................................16
2.2 Detailed Description of AT Commands According to V.25TER...........................................17
2.2.1 A/ Re-issues the Last Command Given.......................................................................17
2.2.2 ATA ANSWER AN INCOMING CALL ....................................................................17
2.2.3 ATD Mobile Originated Call to Dial A Number..........................................................18
2.2.4 ATD><n> Originate Call to Phone Number in Current Memory................................20
2.2.5 ATD><str> Originate Call to Phone Number in Memory Which Corresponds to Field
<str>........................................................................................................................................21
2.2.6 ATDL Redial Last Telephone Number Used...............................................................23
2.2.7 ATE Set Command Echo Mode ..................................................................................23
2.2.8 ATH Disconnect Existing Connection.........................................................................24
2.2.9 ATI Display Product Identification Information .........................................................25
2.2.10 ATL Set Monitor speaker loudness............................................................................25
2.2.11 ATM Set Monitor Speaker Mode ..............................................................................25
2.2.12 +++ Switch from Data Mode or PPP Online Mode to Command Mode ..................25
2.2.13 ATO Switch from Command Mode to Data Mode....................................................26
2.2.14 ATP Select Pulse Dialling..........................................................................................26
2.2.15 ATQ Set Result Code Presentation Mode..................................................................26
2.2.16 ATS0 Set Number of Rings before Automatically Answering the Call.....................27
2.2.17 ATS3 Set Command Line Termination Character.....................................................27
2.2.18 ATS4 Set Response Formatting Character ................................................................28
2.2.19 ATS5 Set Command Line Editing Character.............................................................28
2.2.20 ATS6 Pause Before Blind Dialling............................................................................29
2.2.21 ATS7 Set Number of Seconds to Wait for Connection Completion..........................29
2.2.22 ATS8 Set Number of Seconds to Wait for Comma Dial Modifier Encountered in Dial
String of D Command .............................................................................................................30
2.2.23 ATS10 Set Disconnect Delay after Indicating the Absence of Data Carrier..............30

2.2.24 ATT Select Tone Dialing ...........................................................................................31
2.2.25 ATV TA Response Format .......................................................................................31
2.2.26 ATX Set CONNECT Result Code Format and Monitor Call Progress .....................32
2.2.27 ATZ Reset Default Configuration .............................................................................32
2.2.28 AT&C Set DCD Function Mode ...............................................................................33
2.2.29 AT&D Set DTR Function Mode................................................................................34
2.2.30 AT&F Factory Defined Configuration ......................................................................34
2.2.31 AT&V Display Current Configuration ......................................................................36
2.2.32 AT&W Store Active Profile ......................................................................................36
2.2.33 AT+GCAP Request Complete TA Capabilities List..................................................37
2.2.34 AT+GMI Request Manufacturer Identification .........................................................37
2.2.35 AT+GMM Request TA Model Identification ............................................................38
2.2.36 AT+GMR Request TA Revision Identification of Software Release.........................38
2.2.37 AT+GOI Request Global Object Identification.........................................................38
2.2.38 AT+GSN Request TA Serial Number Identification (IMEI) .....................................39
2.2.39 AT+ICF Set TE-TA Control Character Framing........................................................39
2.2.40 AT+IFC Set TE-TA Local Data Flow Control..........................................................40
2.2.41 AT+IPR Set TE-TA Fixed Local Rate .......................................................................41
2.2.42 AT+HVOIC Disconnect Voice Call Only..................................................................42
3 AT Commands According to GSM07.07.....................................................................................43
3.1 Overview of AT Command According to GSM07.07 ...........................................................43
3.2 Detailed Descriptions of AT Command According to GSM07.07 ........................................44
3.2.1 AT+CACM Accumulated Call Meter (ACM) Reset or Query....................................44
3.2.2 AT+CAMM Accumulated Call Meter Maximum (ACM max) Set or Query .............45
3.2.3 AT+CAOC Advice of Charge .....................................................................................46
3.2.4 AT+CBST Select Bearer Service Type........................................................................47
3.2.5 AT+CCFC Call Forwarding Number and Conditions Control....................................48
3.2.6 AT+CCWA Call Waiting Control ................................................................................49
3.2.7AT+CEER Extended Error Report ...............................................................................51
3.2.8 AT+CGMI Request Manufacturer Identification ........................................................53
3.2.9 AT+CGMM Request Model Identification..................................................................53
3.2.10 AT+CGMR Request TA Revision Identification of Software Release......................54
3.2.11 AT+CGSN Request Product Serial Number Identification (Identical with +GSN)...54
3.2.12 AT+CSCS Select TE Character Set...........................................................................55
3.2.13 AT+CSTA Select Type of Address ............................................................................56
3.2.14 AT+CHLD Call Hold and Multiparty........................................................................56
3.2.15 AT+CIMI Request International Mobile Subscriber Identity....................................57
3.2.16 AT+CLCC List Current Calls of ME.........................................................................58
3.2.17 AT+CLCK Facility Lock...........................................................................................60
3.2.18 AT+CLIP Calling Line Identification Presentation ...................................................61
3.2.19 AT+CLIR Calling Line Identification Restriction.....................................................62
3.2.20 AT+CMEE Report Mobile Equipment Error.............................................................63
3.2.21 AT+COLP Connected Line Identification Presentation ............................................64
3.2.22 AT+COPS Operator Selection...................................................................................66

3.2.23 AT+CPAS Phone Activity Status...............................................................................67
3.2.24 AT+CPBF Find Phonebook Entries...........................................................................67
3.2.25 AT+CPBR Read Current Phonebook Entries............................................................69
3.2.26 AT+CPBS Select Phonebook Memory Storage.........................................................69
3.2.27 AT+CPBW Write Phonebook Entry..........................................................................71
3.2.28 AT+CPIN Enter PIN..................................................................................................72
3.2.29 AT+CPWD Change Password...................................................................................73
3.2.30 AT+CR Service Reporting Control ...........................................................................74
3.2.31 AT+CRC Set Cellular Result Codes for Incoming Call Indication ...........................74
3.2.32 AT+CREG Network Registration..............................................................................75
3.2.33 AT+CRLP Select Radio Link Protocol Parameters...................................................77
3.2.34 AT+CRSM Restricted SIM Access ...........................................................................77
3.2.35 AT+CSQ Signal Quality Report................................................................................78
3.2.36 AT+FCLASS FAX: Select, Read or Test Service Class ............................................79
3.2.37 AT+FMI FAX: Report Manufactured ID...................................................................80
3.2.38 AT+FMM FAX: Report Model ID ............................................................................80
3.2.39 AT+FMR FAX: Report Revision ID .........................................................................80
3.2.40 AT+VTD Tone Duration............................................................................................81
3.2.41 AT+VTS DTMF and Tone Generation......................................................................81
3.2.42 AT+CMUX Multiplexer Control...............................................................................82
3.2.43 AT+CNUM Subscriber Number................................................................................84
3.2.44 AT+CPOL Preferred Operator List............................................................................85
3.2.45 AT+COPN Read Operator Names.............................................................................85
3.2.46 AT+CFUN Set Phone Functionality..........................................................................86
3.2.47 AT+CCLK Clock.......................................................................................................87
3.2.48 AT+CSIM Generic SIM Access ................................................................................87
3.2.49 AT+CALM Alert Sound Mode..................................................................................88
3.2.50 AT+CALS Alert Sound Select...................................................................................89
3.2.51 AT+CRSL Ringer Sound Level.................................................................................89
3.2.52 AT+CLVL Loud Speaker Volume Level ...................................................................90
3.2.53 AT+CMUT Mute Control..........................................................................................91
3.2.54 AT+CPUC Price Per Unit and Currency Table..........................................................92
3.2.55 AT+CCWE Call Meter Maximum Event ..................................................................92
3.2.56 AT+CBC Battery Charge...........................................................................................93
3.2.57 AT+CUSD Unstructured Supplementary Service Data.............................................94
3.2.58 AT+CSSN Supplementary Services Notification......................................................95
4 AT Commands According to GSM07.05.....................................................................................97
4.1 Overview of AT Commands According to GSM07.05..........................................................97
4.2 Detailed Descriptions of AT Commands According to GSM07.05.......................................97
4.2.1 AT+CMGD Delete SMS Message...............................................................................97
4.2.2 AT+CMGF Select SMS Message Format ...................................................................98
4.2.3 AT+CMGL List SMS Messages from Preferred Store................................................99
4.2.4 AT+CMGR Read SMS Message...............................................................................102
4.2.5 AT+CMGS Send SMS Message................................................................................105

4.2.6 AT+CMGW Write SMS Message to Memory ..........................................................106
4.2.7 AT+CMSS Send SMS Message from Storage ..........................................................108
4.2.8 AT+CNMI New SMS Message Indications ..............................................................108
4.2.9 AT+CPMS Preferred SMS Message Storage ............................................................ 111
4.2.10 AT+CRES Restore SMS Settings............................................................................ 111
4.2.11 AT+CSAS Save SMS Settings ................................................................................112
4.2.12 AT+CSCA SMS Service Center Address ................................................................113
4.2.13 AT+CSCB Select Cell Broadcast SMS Messages...................................................114
4.2.14 AT+CSDH Show SMS Text Mode Parameters .......................................................115
4.2.15 AT+CSMP Set SMS Text Mode Parameters ...........................................................115
4.2.16 AT+CSMS Select Message Service.........................................................................116
5 AT Commands for SIM Application Toolkit.............................................................................118
5.1 STK AT Command..............................................................................................................118
6 AT Commands Special for SIMCOM........................................................................................120
6.1 Overview.............................................................................................................................120
6.2 Detailed Descriptions of Commands...................................................................................121
6.2.1 AT+SIDET Change the Side Tone Gain Level.......................................................121
6.2.2 AT+CPOWD Power Off...........................................................................................122
6.2.3 AT+SPIC Times Remained to Input SIM PIN/PUK.................................................122
6.2.4 AT+CMIC Change the Microphone Gain Level.......................................................123
6.2.5 AT+CALA Set Alarm Time......................................................................................124
6.2.6 AT+CALD Delete Alarm..........................................................................................125
6.2.7 AT+CADC Read ADC .............................................................................................125
6.2.8 AT+CSNS Single Numbering Scheme .....................................................................125
6.2.9 AT+CDSCB Reset Cell Broadcast............................................................................126
6.2.10 AT+CMOD Configure Alternating Mode Calls .....................................................126
6.2.11 AT+CFGRI Indicate RI When Using URC ............................................................127
6.2.12 AT+CLTS Get Local Timestamp............................................................................127
6.2.13 AT+CEXTHS External Headset Jack Control........................................................129
6.2.14 AT+CEXTBUT Headset Button Status Reporting .................................................130
6.2.15 AT+CSMINS SIM Inserted Status Reporting.........................................................131
6.2.16 AT+CLDTMF Local DTMF Tone Generation.......................................................131
6.2.17 AT+CDRIND CS Voice/Data Call Termination Indication ...................................132
6.2.18 AT+CSPN Get Service Provider Name from SIM ..................................................133
6.2.19 AT+CCVM Get and Set the Voice Mail Number on the SIM .................................133
6.2.20 AT+CBAND Get and Set Mobile Operation Band .................................................134
6.2.21 AT+CHF Configure Hands Free Operation.............................................................135
6.2.22 AT+CHFA Swap the Audio Channels .....................................................................135
6.2.23 AT+CSCLK Configure Slow Clock........................................................................136
6.2.24 AT+CENG Switch On or Off Engineering Mode ...................................................137
6.2.25 AT+SCLASS0 Store Class 0 SMS to SIM When Received Class 0 SMS ..............139
6.2.26 AT+CCID Show ICCID ..........................................................................................139
6.2.27 AT+CMTE Set Critical Temperature Operating Mode or Query Temperature......139
6.2.28 AT+CBTE Battery Temperature Query...................................................................140

6.2.29 AT+CSDT Switch On or Off Detecting SIM Card.................................................140
6.2.30 AT+CMGDA Delete All SMS................................................................................141
6.2.31 AT+STTONE Play SIM Toolkit Tone....................................................................142
6.2.32 AT+SIMTONE Generate Specifically Tone...........................................................143
6.2.33 AT+CCPD Enable or Disable Alpha String............................................................143
6.2.34 AT+CGID Get SIM Card Group Identifier.............................................................144
6.2.35 AT+MORING Show State of Mobile Originated Call............................................144
6.2.36 AT+CMGHEX Enable or Disable Sending Non-ASCII Character SMS ...............145
6.2.37AT+AUTEST Audio Channel Loopback Test.........................................................146
6.2.38AT+CCODE Configure SMS Code Mode...............................................................146
6.2.39 AT+CIURC Enable or Disable Initial URC Presentation.......................................147
6.2.40 AT+CPSPWD Change PS Super Password............................................................147
6.2.41 AT+EXUNSOL Enable or Disable Proprietary Unsolicited Indications.................148
6.2.42 AT+CGMSCLASS Change GPRS Multislot Class ................................................148
6.2.43 AT+CDEVICE View Current Flash Device Type..................................................149
6.2.44 AT+CCALR Call Ready Query..............................................................................149
6.2.45 AT+GSV Display Product Identification Information.............................................150
6.2.46 AT+SGPIO Control the GPIO.................................................................................150
6.2.47 AT+SPWM Generate the Pulse-Width-Modulation ................................................151
6.2.48 AT+ECHO Echo Cancellation Control ...................................................................152
6.2.49 AT+CAAS Control Auto Audio Switch ..................................................................153
6.2.50 AT+SVR Configure Voice Coding Type for Voice Calls.........................................154
6.2.51 AT+GSMBUSY Reject Incoming Call....................................................................155
7 AT Commands for GPRS Support.............................................................................................156
7.1 Overview of AT Commands for GPRS Support..................................................................156
7.2 Detailed Descriptions of AT Commands for GPRS Support...............................................156
7.2.1 AT+CGATT Attach or Detach from GPRS Service ..................................................156
7.2.2 AT+CGDCONT Define PDP Context.......................................................................157
7.2.3 AT+CGQMIN Quality of Service Profile (Minimum Acceptable) ...........................159
7.2.4 AT+CGQREQ Quality of Service Profile (Requested) .............................................160
7.2.5 AT+CGACT PDP Context Activate or Deactivate....................................................162
7.2.6 AT+CGDATA Enter Data State.................................................................................162
7.2.7 AT+CGPADDR Show PDP Address.........................................................................163
7.2.8 AT+CGCLASS GPRS Mobile Station Class.............................................................164
7.2.9 AT+CGEREP Control Unsolicited GPRS Event Reporting......................................165
7.2.10 AT+CGREG Network Registration Status ..............................................................166
7.2.11 AT+CGSMS Select Service for MO SMS Messages ..............................................167
8 AT Commands for TCPIP Application Toolkit .........................................................................169
8.1 Overview.............................................................................................................................169
8.2.1 AT+CIPMUX Start Up Multi-IP Connection............................................................170
8.2.2 AT+CIPSTART Start Up TCP or UDP Connection...................................................170
8.2.3 AT+CIPSEND Send Data Through TCP or UDP Connection...................................172
8.2.4 AT+CIPQSEND Select Data Transmitting Mode .....................................................174

8.2.5 AT+CIPACK Query Previous Connection Data Transmitting State..........................175
8.2.6 AT+CIPCLOSE Close TCP or UDP Connection .....................................................176
8.2.7 AT+CIPSHUT Deactivate GPRS PDP Context ........................................................176
8.2.8 AT+CLPORT Set Local Port.....................................................................................177
8.2.9 AT+CSTT Start Task and Set APN, USER NAME, PASSWORD...........................177
8.2.10 AT+CIICR Bring Up Wireless Connection with GPRS or CSD .............................178
8.2.11 AT+CIFSR Get Local IP Address............................................................................179
8.2.12 AT+CIPSTATUS Query Current Connection Status ...............................................179
8.2.13 AT+CDNSCFG Configure Domain Name Server...................................................181
8.2.14 AT+CDNSGIP Query the IP Address of Given Domain Name...............................181
8.2.15 AT+CIPHEAD Add an IP Head at the Beginning of a Package Received..............182
8.2.16 AT+CIPATS Set Auto Sending Timer .....................................................................183
8.2.17 AT+CIPSPRT Set Prompt of ‘>’ When Module Sends Data...................................183
8.2.18 AT+CIPSERVER Configure Module as Server ......................................................184
8.2.19 AT+CIPCSGP Set CSD or GPRS for Connection Mode ........................................185
8.2.20 AT+CIPSRIP Show Remote IP Address and Port When Received Data................186
8.2.21 AT+CIPDPDP Set Whether to Check State of GPRS Network Timing..................187
8.2.22 AT+CIPMODE Select TCPIP Application Mode....................................................188
8.2.23AT+CIPCCFG Configure Transparent Transfer Mode ............................................188
8.2.24 AT+CIPSHOWTP Display Transfer Protocol in IP Head When Received Data.....189
8.2.25 AT+CIPUDPMODE UDP Extended Mode.............................................................190
8.2.26 AT+CIPRXGET Get Data from Network Manually ...............................................191
8.2.27 AT+CIPQRCLOSE Quick Remote Close ...............................................................192
8.2.28 AT+CIPSCONT Save TCPIP Application Context.................................................192
9 AT Commands for IP Application .............................................................................................194
9.1 Overview.............................................................................................................................194
9.2.1 AT+SAPBR Bearer Settings for Applications Based on IP.......................................194
10 AT Commands for HTTP Application.....................................................................................196
10.1 Overview...........................................................................................................................196
10.2 Detailed Descriptions of Commands.................................................................................196
10.2.1 AT+HTTPINIT Initialize HTTP Service.................................................................196
10.2.2 AT+HTTPTERM Terminate HTTP Service............................................................196
10.2.3 AT+HTTPPARA Set HTTP Parameters Value ........................................................197
10.2.4 AT+HTTPDATA Input HTTP Data.........................................................................198
10.2.5 AT+HTTPACTION HTTP Method Action .............................................................199
10.2.6 AT+HTTPREAD Read the HTTP Server Response................................................201
10.2.7 AT+HTTPSCONT Save HTTP Application Context ..............................................202
11 AT Commands for FTP Application........................................................................................203
11.1 Overview...........................................................................................................................203
11.2 Detailed Descriptions of Commands.................................................................................203
11.2.1 AT+FTPPORT Set FTP Control Port.......................................................................203
11.2.2 AT+FTPMODE Set Active or Passive FTP Mode...................................................204
11.2.3 AT+FTPTYPE Set the Type of Data to Be Transferred...........................................205

11.2.4 AT+FTPPUTOPT Set FTP Put Type .......................................................................205
11.2.5 AT+FTPCID Set FTP Bearer Profile Identifier .......................................................206
11.2.6 AT+FTPREST Set Resume Broken Download .......................................................206
11.2.7 AT+FTPSERV Set FTP Server Address ..................................................................207
11.2.8 AT+FTPUN Set FTP User Name ............................................................................208
11.2.9 AT+FTPPW Set FTP Password...............................................................................208
11.2.10 AT+FTPGETNAME Set Download File Name ....................................................209
11.2.11 AT+FTPGETPATH Set Download File Path.........................................................209
11.2.12 AT+FTPPUTNAME Set Upload File Name .........................................................210
11.2.13 AT+FTPPUTPATH Set Upload File Path..............................................................211
11.2.14 AT+FTPGET Download File.................................................................................211
11.2.15 AT+FTPPUT Set Upload File................................................................................212
11.2.16 AT+FTPSCONT Save FTP Application Context ..................................................213
12 Supported Unsolicited Result Codes........................................................................................215
12.1 Summary of CME ERROR Codes....................................................................................215
12.2 Summary of CMS ERROR Codes ....................................................................................216
13 AT Commands Sample ............................................................................................................219
13.1 Profile Commands.............................................................................................................219
13.2 SIM Commands ................................................................................................................220
13.3 General Commands...........................................................................................................221
13.4 Call Control Commands....................................................................................................222
13.5 SIM Toolkit Commands....................................................................................................224
13.6 Audio Commands..............................................................................................................224
13.7 SMS Commands ...............................................................................................................224
13.8 GPRS Commands .............................................................................................................226

1 Introduction
1.1 Scope of the document
This document presents the AT Command Set for SIMCOM SIM900 series cellular engine.
1.2 Related documents
You can visit the SIMCom Website using the following link:
http://www.sim.com

1.3 Conventions and abbreviations
In this document, the GSM engines are referred to as following term:
1) ME (Mobile Equipment);
2) MS (Mobile Station);
3) TA (Terminal Adapter);
4) DCE (Data Communication Equipment) or facsimile DCE (FAX modem, FAX board);
In application, controlling device controls the GSM engine by sending AT Command via its serial
interface. The controlling device at the other end of the serial line is referred to as following term:
1) TE (Terminal Equipment);
2) DTE (Data Terminal Equipment) or plainly "the application" which is running on an
embedded system;
1.4 AT Command syntax
The "AT" or "at" prefix must be set at the beginning of each Command line. To terminate a
Command line enter <CR>.
Commands are usually followed by a response that includes. "<CR><LF><response><CR><LF>"
Throughout this document, only the responses are presented, <CR><LF> are omitted
intentionally.
The AT Command set implemented by SIM900 is a combination of GSM07.05, GSM07.07 and
ITU-T recommendation V.25ter and the AT commands developed by SIMCom.
Note: A HEX string such as "00 49 49 49 49 FF FF FF FF" will be sent out through serial
port at the baud rate of 115200 immediately after SIM900 is powered on. The string shall be
ignored since it is used for synchronization with PC tool. Only enter AT Command through
serial port after SIM900 is powered on and Unsolicited Result Code "RDY" is received from
serial port. If auto-bauding is enabled, the Unsolicited Result Codes "RDY" and so on are
not indicated when you start up the ME, and the "AT" prefix, not "at" prefix must be set at
the beginning of each command line.
All these AT commands can be split into three categories syntactically: "basic", "S parameter",
and "extended". These are as follows:
1.4.1 Basic syntax
These AT commands have the format of "AT<x><n>", or "AT&<x><n>", where "<x>"is the
Command, and "<n>"is/are the argument(s) for that Command. An example of this is "ATE<n>",
which tells the DCE whether received characters should be echoed back to the DTE according to
the value of "<n>". "<n>" is optional and a default will be used if missing.

1.4.2 S Parameter syntax
These AT commands have the format of "ATS<n>=<m>", where "<n>" is the index of the S
register to set, and "<m>"is the value to assign to it. "<m>" is optional; if it is missing, then a
default value is assigned.
1.4.3 Extended Syntax
These commands can operate in several modes, as in the following table:
Table 1: Types of AT commands and responses
Test Command AT+<x>=? The mobile equipment returns the list of parameters
and value ranges set with the corresponding Write
Command or by internal processes.
Read Command AT+<x>? This command returns the currently set value of the
parameter or parameters.
Write Command AT+<x>=<…> This command sets the user-definable parameter
values.
Execution Command AT+<x> The execution command reads non-variable
parameters affected by internal processes in the GSM
engine.
1.4.4 Combining AT commands on the same Command line
You can enter several AT commands on the same line. In this case, you do not need to type the
"AT" or "at" prefix before every command. Instead, you only need type "AT" or "at" the
beginning of the command line. Please note to use a semicolon as the command delimiter after an
extended command, for example: ATE1&W&F+ICF?; +CFUN?; &W.
The Command line buffer can accept a maximum of 556 characters. If the characters entered
exceeded this number then none of the Command will executed and TA will return "ERROR".
1.4.5 Entering successive AT commands on separate lines
When you need to enter a series of AT commands on separate lines, please Note that you need to
wait the final response (for example OK, CME error, CMS error) of last AT Command you entered
before you enter the next AT Command.
1.5 Supported character sets
The SIM900 AT Command interface defaults to the IRA character set. The SIM900 supports the
following character sets:
• GSM format
• UCS2

• HEX
• IRA
• PCCP
• PCDN
• 8859-1
The character set can be set and interrogated using the "AT+CSCS" Command (GSM 07.07).
The character set is defined in GSM specification 07.05.
The character set affects transmission and reception of SMS and SMS Cell Broadcast messages,
the entry and display of phone book entries text field and SIM Application Toolkit alpha strings.
1.6 Flow control
Flow control is very important for correct communication between the GSM engine and DTE. For
in the case such as a data or fax call, the sending device is transferring data faster than the
receiving side is ready to accept. When the receiving buffer reaches its capacity, the receiving
device should be capable to cause the sending device to pause until it catches up.
There are basically two approaches to achieve data flow control: software flow control and
hardware flow control. SIM900 support both two kinds of flow control.
In Multiplex mode, it is recommended to use the hardware flow control.
1.6.1 Software flow control (XON/XOFF flow control)
Software flow control sends different characters to stop (XOFF, decimal 19) and resume (XON,
decimal 17) data flow. It is quite useful in some applications that only use three wires on the serial
interface.
The default flow control approach of SIM900 is hardware flow control (RTS/CTS flow control), to
enable software flow control in the DTE interface and within GSM engine, type the following AT
Command:
AT+IFC=1, 1
This setting is stored volatile, for use after restart, AT+IFC=1, 1 should be stored to the user
profile with AT&W.
NOTE:
The AT commands listed in the table of AT&W chapter should be stored to user profile with
AT&W for use after restart. Most other AT commands in V.25, 07.05, 07.07, GPRS will store
parameters automatically and can be used after module restart.
Ensure that any communications software package (e.g. Hyper terminal) uses software flow
control.
NOTE:
Software Flow control should not be used for data calls where binary data will be transmitted or

received (e.g. TCP/IP) as the DTE interface may interpret binary data as flow control characters.
1.6.2 Hardware flow control (RTS/CTS flow control)
Hardware flow control achieves the data flow control by controlling the RTS/CTS line. When the
data transfer should be suspended, the CTS line is set inactive until the transfer from the receiving
buffer has completed. When the receiving buffer is ok to receive more data, CTS goes active once
again.
To achieve hardware flow control, ensure that the RTS/CTS lines are present on your application
platform.

2 AT Commands According to V.25TER
These AT Commands are designed according to the ITU-T (International Telecommunication
Union, Telecommunication sector) V.25ter document.
2.1 Overview of AT Commands According to V.25TER
Command Description
A/ RE-ISSUES THE LAST COMMAND GIVEN
ATA ANSWER AN INCOMING CALL
ATD MOBILE ORIGINATED CALL TO DIAL A NUMBER
ATD><N> ORIGINATE CALL TO PHONE NUMBER IN CURRENT MEMORY
ATD><STR> ORIGINATE CALL TO PHONE NUMBER IN MEMORY WHICH
CORRESPONDS TO FIELD <STR>
ATDL REDIAL LAST TELEPHONE NUMBER USED
ATE SET COMMAND ECHO MODE
ATH DISCONNECT EXISTING CONNECTION
ATI DISPLAY PRODUCT IDENTIFICATION INFORMATION
ATL SET MONITOR SPEAKER LOUDNESS
ATM SET MONITOR SPEAKER MODE
+++ SWITCH FROM DATA MODE OR PPP ONLINE MODE TO
COMMAND MODE
ATO SWITCH FROM COMMAND MODE TO DATA MODE
ATP SELECT PULSE DIALLING
ATQ SET RESULT CODE PRESENTATION MODE
ATS0 SET NUMBER OF RINGS BEFORE AUTOMATICALLY
ANSWERING THE CALL
ATS3 SET COMMAND LINE TERMINATION CHARACTER
ATS4 SET RESPONSE FORMATTING CHARACTER
ATS5 SET COMMAND LINE EDITING CHARACTER
ATS6 PAUSE BEFORE BLIND DIALLING
ATS7 SET NUMBER OF SECONDS TO WAIT FOR CONNECTION
COMPLETION
ATS8 SET NUMBER OF SECONDS TO WAIT FOR COMMA DIAL
MODIFIER ENCOUNTERED IN DIAL STRING OF D COMMAND
ATS10 SET DISCONNECT DELAY AFTER INDICATING THE ABSENCE OF
DATA CARRIER
ATT SELECT TONE DIALING
ATV TA RESPONSE FORMAT
ATX SET CONNECT RESULT CODE FORMAT AND MONITOR CALL

PROGRESS
ATZ RESET DEFAULT CONFIGURATION
AT&C SET DCD FUNCTION MODE
AT&D SET DTR FUNCTION MODE
AT&F FACTORY DEFINED CONFIGURATION
AT&V DISPLAY CURRENT CONFIGURATION
AT&W STORE ACTIVE PROFILE
AT+GCAP REQUEST COMPLETE TA CAPABILITIES LIST
AT+GMI REQUEST MANUFACTURER IDENTIFICATION
AT+GMM REQUEST TA MODEL IDENTIFICATION
AT+GMR REQUEST TA REVISION IDENTIFICATION OF SOFTWARE
RELEASE
AT+GOI REQUEST GLOBAL OBJECT IDENTIFICATION
AT+GSN REQUEST TA SERIAL NUMBER IDENTIFICATION (IMEI)
AT+ICF SET TE-TA CONTROL CHARACTER FRAMING
AT+IFC SET TE-TA LOCAL DATA FLOW CONTROL
AT+IPR SET TE-TA FIXED LOCAL RATE
AT+HVOIC DISCONNECT VOICE CALL ONLY
2.2 Detailed Description of AT Commands According to V.25TER
2.2.1 A/ Re-issues the Last Command Given
A/ Re-issues the Last Command Given
Execution
Command
A/
Response
Re-issues the previous Command
Reference
V.25ter
Note
2.2.2 ATA ANSWER AN INCOMING CALL
ATA ANSWER AN INCOMING CALL

Execution
Command
ATA
Response
TA sends off-hook to the remote station.
Note1: Any additional commands on the same Command line are ignored.
Note2: This Command may be aborted generally by receiving a character
during execution. The aborting is not possible during some states of
connection establishment such as handshaking.
Response in case of data call, if successfully connected
CONNECT<text> TA switches to data mode.
Note: <text> output only if ATX<value> parameter setting with the
<value>>0
When TA returns to Command mode after call release
OK
Response in case of voice call, if successfully connected
OK
Response if no connection
NO CARRIER
Reference
V.25ter
Note
See also ATX
2.2.3 ATD Mobile Originated Call to Dial A Number
ATD Mobile Originated Call to Dial A Number
Execution
Command
ATD<n>[<mgsm
][;]
Response
This Command can be used to set up outgoing voice, data or fax calls. It
also serves to control supplementary services.
Note: This Command may be aborted generally by receiving an ATH
Command or a character during execution. The aborting is not possible
during some states of connection establishment such as handshaking.
If no dial tone and (parameter setting ATX2 or ATX4)
NO DIALTONE
If busy and (parameter setting ATX3 or ATX4)
BUSY
If a connection cannot be established
NO CARRIER
If the remote station does not answer
NO ANSWER

If connection successful and non-voice call.
<value> >0
OK
If connection successful and voice call
OK
Parameters
<n> String of dialing digits and optionally V.25ter modifiers dialing
digits:
0-9, * , #, +, A, B, C
Following V.25ter modifiers are ignored:
,(comma), T, P, !, W, @
Emergency call:
<n> Standardized emergency number 112 (no SIM needed)
<mgsm> String of GSM modifiers:
I Actives CLIR (Disables presentation of own number
to called party)
i Deactivates CLIR (Enable presentation of own number
to called party)
G Activates Closed User Group invocation for this call
only
g Deactivates Closed User Group invocation for this call
only
<;> Only required to set up voice call , return to Command state
Reference
V.25ter
Note
Parameter "I" and "i" only if no *# code is within the dial string
<n> is default for last number that can be dialed by ATDL
*# codes sent with ATD are treated as voice calls. Therefore, the
Command must be terminated with a semicolon ";"
See ATX Command for setting result code and call monitoring
parameters.
Responses returned after dialing with ATD
For voice call two different responses mode can be determined. TA
returns "OK" immediately either after dialing was completed or after
the call is established. The setting is controlled by AT+COLP. Factory
default is AT+COLP=0, this cause the TA returns "OK" immediately

after dialing was completed, otherwise TA will returns "OK",
"BUSY", "NO DIAL TONE", "NO CARRIER".
Using ATD during an active voice call:
When a user originates a second voice call while there is already an
active voice call, the first call will be automatically put on hold.
The current states of all calls can be easily checked at any time by
using the AT+CLCC Command.
2.2.4 ATD><n> Originate Call to Phone Number in Current Memory
ATD><n> Originate Call to Phone Number in Current Memory
Execution
Command
ATD><n>[<clir>
][ <cug>][;]
Response
This Command can be used to dial a phone number from current phonebook
memory.
If error is related to ME functionality
+CME ERROR: <err>
NO DIALTONE
BUSY
NO CARRIER
NO ANSWER
<value> >0
OK
If successfully connected and voice call

OK
Parameters
<n> Integer type memory location should be in the range of
locations available in the memory used
<clir>
I Override the CLIR supplementary service subscription
default value for this call
Invocation (restrict CLI presentation)
i Override the CLIR supplementary service subscription
default value for this call
Suppression (allow CLI presentation)
<cug>
G Control the CUG supplementary service information
for this call
CUG Not supported
g Control the CUG supplementary service information
for this call
CUG Not supported
<;> Only required to set up voice call , return to Command state
Reference
V.25ter
Note
parameters.
2.2.5 ATD><str> Originate Call to Phone Number in Memory Which Corresponds to Field
<str>
ATD><str> Originate Call to Phone Number in Memory Which Corresponds to Field
<str>
Execution
Command
ATD><str>[<clir
>][<cug>][;]
Response
This Command make the TA attempts to set up an outgoing call to stored
number.
All available memories are searched for the entry <str>.
+CME ERROR: <err>

NO DIALTONE
BUSY
NO CARRIER
NO ANSWER
<value> >0
OK
OK
Parameters
<str> String type (string should be included in quotation marks)
value ("x"), which should equal to an alphanumeric field in
at least one phone book entry in the searched memories. str
formatted as current TE character set specified by +CSCS.
I Actives CLIR (Disables presentation of own number
to called party)
i Deactivates CLIR (Enable presentation of own number
to called party)
G Activates Closed User Group invocation for this call
only
g Deactivates Closed User Group invocation for this call
only
<;> only required to set up voice call , return to Command state
Reference
V.25ter
Note
parameters.

2.2.6 ATDL Redial Last Telephone Number Used
ATDL Redial Last Telephone Number Used
Execution
Command
ATDL
Response
This Command redials the last voice and data call number used.
+CME ERROR: <err>
NO DIALTONE
BUSY
NO CARRIER
NO ANSWER
<value> >0
OK
OK
Reference
V.25ter
Note
parameters.
Return the numbers and symbols which ATD supports if there is no
last dialing context.
2.2.7 ATE Set Command Echo Mode
ATE Set Command Echo Mode
Execution Response

This setting determines whether or not the TA echoes characters received
from TE during Command state.
OK
Command
ATE<value>
Parameter
<value> 0 Echo mode off
1 Echo mode on
Reference
V.25ter
Note
2.2.8 ATH Disconnect Existing Connection
ATH Disconnect Existing Connection
Response
Disconnect existing call by local TE from Command line and terminate call
OK
Note: OK is issued after circuit 109(DCD) is turned off, if it was previously
on.
Execution
Command
ATH[n]
Parameter
<n> 0 Disconnect ALL calls on the channel the command is
requested. All active or waiting calls, CS data calls, GPRS call
of the channel will be disconnected.
1 Disconnect all calls on ALL connected channels. All active or
waiting calls, CSD calls, GPRS call will be disconnected.
(clean up of all calls of the ME)
2 Disconnect all connected CS data call only on the channel
the command is requested. (speech calls (active or waiting)
or GPRS calls are not disconnected)
3 Disconnect all connected GPRS calls only on the channel
the command is requested (speech calls (active or waiting)
or CS data calls are not disconnected.
4 Disconnect all CS calls (either speech or data) but does not
disconnect waiting call (either speech or data) on the
channel the command is requested.
5 Disconnect waiting call (either speech or data) but does not
disconnect other active calls (either CS speech, CS data or
GPRS) on the channel the command is requested.
(rejection of incoming call)
Reference
V.25ter
Note

2.2.9 ATI Display Product Identification Information
ATI Display Product Identification Information
Execution
Command
ATI
Response
TA issues product information text
Example:
SIM900 R11.0
OK
Reference
V.25ter
Note
2.2.10 ATL Set Monitor speaker loudness
ATL Set Monitor speaker loudness
Response
OK
Execution
Command
ATL<value> Parameter
<value> 0..9 volume
Reference
V.25ter
Note
No effect in GSM
2.2.11 ATM Set Monitor Speaker Mode
ATM Set Monitor Speaker Mode
Response
OK
Execution
Command
ATM<value> Parameter
<value> 0..9 mode
Reference
V.25ter
Note
No effect in GSM
2.2.12 +++ Switch from Data Mode or PPP Online Mode to Command Mode
+++ Switch from Data Mode or PPP Online Mode to Command Mode
Execution
Command
+++
Response
The +++ character sequence causes the TA to cancel the data flow over the
AT interface and switch to Command mode. This allows you to enter AT
Command while maintaining the data connection to the remote server.
OK
To prevent the +++ escape sequence from being misinterpreted as data, it
should comply to following sequence:

1. No characters entered for T1 time (1 second)
2. "+++" characters entered with no characters in between (0.5 second)
3. No characters entered for T1 timer (0.5 second)
4. Switch to Command mode, otherwise go to step 1.
Parameter
Reference
V.25ter
Note
To return from Command mode back to data mode: Enter ATO.
2.2.13 ATO Switch from Command Mode to Data Mode
ATO Switch from Command Mode to Data Mode
Response
TA resumes the connection and switches back from Command mode to data
mode.
CONNECT
If connection is not successfully resumed
NO CARRIER
else
TA returns to data mode from Command mode CONNECT <text> Note:
<text> only if parameter setting ATX>0
Execution
Command
ATO[n]
Parameter
<n> 0 Switch from Command mode to data mode.
Reference
V.25ter
Note
2.2.14 ATP Select Pulse Dialling
ATP Select Pulse Dialling
Execution
Command
ATP
Response
OK
Reference
V.25ter
Note
No effect in GSM
2.2.15 ATQ Set Result Code Presentation Mode
ATQ Set Result Code Presentation Mode
Execution
Command
ATQ<n>
Response
This parameter setting determines whether or not the TA transmits any result
code to the TE. Information text transmitted in response is not affected by
this setting.

If <n>=0:
OK
If <n>=1:
(none)
Parameter
<n> 0 TA transmits result code
1 Result codes are suppressed and not transmitted
Reference
V.25ter
Note
2.2.16 ATS0 Set Number of Rings before Automatically Answering the Call
ATS0 Set Number of Rings before Automatically Answering the Call
Response
<n>
OK
Read Command
ATS0?
Parameter
See Write Command
Response
This parameter setting determines the number of rings before auto-answer.
OK
ERROR
Write Command
ATS0=<n>
Parameter
<n> 0 Automatic answering is disable.
1-255 Number of rings the modem will wait for before answering
the phone if a ring is detected.
Reference
V.25ter
Note
If <n> is set too high, the calling party may hang up before the call can be
answered automatically.
2.2.17 ATS3 Set Command Line Termination Character
ATS3 Set Command Line Termination Character
Response
<n>
OK
Read Command
ATS3?
Parameter
See Write Command
Write Command
ATS3=<n>
Response
This parameter setting determines the character recognized by TA to

terminate an incoming Command line. The TA also returns this character in
output.
OK
ERROR
Parameter
<n> 13 Command line termination character
Reference
V.25ter
Note
Default 13 = CR. It only supports default value.
2.2.18 ATS4 Set Response Formatting Character
ATS4 Set Response Formatting Character
Response
<n>
OK
Read Command
ATS4?
Parameter
See Write Command
Response
This parameter setting determines the character generated by the TA for
result code and information text.
OK
ERROR
Write Command
ATS4=<n>
Parameter
<n> 10 Response formatting character
Reference
V.25ter
Note
Default 10 = LF. It only supports default value.
2.2.19 ATS5 Set Command Line Editing Character
ATS5 Set Command Line Editing Character
Response
<n>
OK
Read Command
ATS5?
Parameter
See Write Command
Write Command
ATS5=<n>
Response
This parameter setting determines the character recognized by TA as a
request to delete from the Command line the immediately preceding

character.
OK
ERROR
Parameter
<n> 0-8-127 Response formatting character
Reference
V.25ter
Note
Default 8 = Backspace.
2.2.20 ATS6 Pause Before Blind Dialling
ATS6 Pause Before Blind Dialling
Read Command
ATS6?
Response
ERROR
Response
OK
ERROR
Write Command
ATS6=<n>
Parameter
<n> 0..999 Time
Reference
V.25ter
Note
No effect in GSM
2.2.21 ATS7 Set Number of Seconds to Wait for Connection Completion
ATS7 Set Number of Seconds to Wait for Connection Completion
Response
<n>
OK
Read Command
ATS7?
Parameter
See Write Command
Response
This parameter setting determines the amount of time to wait for the
connection completion in case of answering or originating a call.
OK
ERROR
Write Command
ATS7=<n>
Parameter
<n> 1-60-255 Number of seconds to wait for connection completion
Reference Note

V.25ter If called party has specified a high value for ATS0=<n>, call setup may
fail.
The correlation between ATS7 and ATS0 is important
Example: Call may fail if ATS7=30 and ATS0=20.
ATS7 is only applicable to data call.
2.2.22 ATS8 Set Number of Seconds to Wait for Comma Dial Modifier Encountered in Dial
String of D Command
ATS8 Set Number of Seconds to Wait for Comma Dial Modifier Encountered in Dial
String of D Command
Response
<n>
OK
Read Command
ATS8?
Parameter
See Write Command
Response
OK
ERROR
Write Command
ATS8=<n>
Parameter
<n> 0-255 The value of this register determines how long the modem
should pause when it sees a comma in the dialing string.
Reference
V.25ter
Note
No effect in GSM
2.2.23 ATS10 Set Disconnect Delay after Indicating the Absence of Data Carrier
ATS10 Set Disconnect Delay after Indicating the Absence of Data Carrier
Response
<n>
OK
Read Command
ATS10?
Parameter
See Write Command
Response
This parameter setting determines the amount of time that the TA will
remain connected in absence of data carrier. If the data carrier is once more
detected before disconnecting, the TA remains connected.
OK
ERROR
Write Command
ATS10=<n>
Parameter

<n> 1-15-254 Number of tenths seconds of delay
Reference
V.25ter
Note
2.2.24 ATT Select Tone Dialing
ATT Select Tone Dialing
Execution
Command
ATT
Response
OK
Reference
V.25ter
Note
No effect in GSM
2.2.25 ATV TA Response Format
ATV TA Response Format
Response
This parameter setting determines the contents of the header and trailer
transmitted with result codes and information responses.
When <value>=0
0
When <value>=1
OK
Execution
Command
ATV<value>
Parameter
<value> 0 Information response: <text><CR><LF>
Short result code format: <numeric code><CR>
1 Information response: <CR><LF><text><CR><LF>
Long result code format: <CR><LF><verbose code>
<CR><LF>
The result codes, their numeric equivalents and brief descriptions of the use
of each are listed in the following table.
Reference
V.25ter
Note
ATV1 ATV0 Description
OK 0 Acknowledges execution of a Command
CONNECT 1 A connection has been established; the DCE is moving
from Command state to online data state
RING 2 The DCE has detected an incoming call signal from
network
NO CARRIER 3 The connection has been terminated or the attempt to
establish a connection failed
ERROR 4 Command not recognized, Command line maximum

length exceeded, parameter value invalid, or other
problem with processing the Command line
NO DIALTONE 6 No dial tone detected
BUSY 7 Engaged (busy) signal detected
NO ANSWER 8 "@" (Wait for Quiet Answer) dial modifier was used,
but remote ringing followed by five seconds of silence
was not detected before expiration of the connection
timer (S7)
PROCEEDING 9 An AT command is being processed
CONNECT
<text>
Manufacturer-
specific
Same as CONNECT, but includes
manufacturer-specific text that may specify DTE speed,
line speed, error control, data compression, or other
status
2.2.26 ATX Set CONNECT Result Code Format and Monitor Call Progress
ATX Set CONNECT Result Code Format and Monitor Call Progress
Response
This parameter setting determines whether or not the TA detected the
presence of dial tone and busy signal and whether or not TA transmits
particular result codes.
OK
ERROR
Execution
Command
ATX<value>
Parameter
<value> 0 CONNECT result code only returned, dial tone and busy
detection are both disabled.
1 CONNECT<text> result code only returned, dial tone and
busy detection are both disabled.
2 CONNECT<text> result code returned, dial tone
detection is enabled, busy detection is disabled.
3 CONNECT<text> result code returned, dial tone
detection is disabled, busy detection is enabled.
4 CONNECT<text> result code returned, dial tone and
busy detection are both enabled.
Reference
V.25ter
Note
2.2.27 ATZ Reset Default Configuration
ATZ Reset Default Configuration
Execution
Command
ATZ[<value>]
Response
TA sets all current parameters to the user defined profile.
OK

ERROR
Parameter
<value> 0 Restore profile 0
1 Restore profile 1
Reference
V.25ter
Note
Parameter impacted by Z command:
Command Parameter name Default value
ATE <echo> 0x01
ATQ <result> 0x00
ATV <format> 0x01
ATX <result> 0x04
AT&C <behavior> 0x01
AT&D <behavior> 0x01
AT+IFC <TA_by_TE> 0x00
AT+IFC <TE_by_TA> 0x00
AT+FCLASS <class> 0x00
ATS0 <num> 0x00
ATS3 <char> 0x00
ATS4 <char> 0x0D
ATS5 <char> 0x0A
ATS7 <time> 0x08
ATS8 <time> 0x32
ATS10 <time> 0x0E
2.2.28 AT&C Set DCD Function Mode
AT&C Set DCD Function Mode
Response
This parameter determines how the state of circuit 109 (DCD) relates to the
detection of received line signal from the distant end.
OK
ERROR
Execution
Command
AT&C[<value>]
Parameter
<value> 0 DCD line is always ON
1 DCD line is ON only in the presence of data carrier
Reference
V.25ter
Note

2.2.29 AT&D Set DTR Function Mode
AT&D Set DTR Function Mode
Response
This parameter determines how the TA responds when circuit 108/2 (DTR)
is changed from the ON to the OFF condition during data mode.
OK
ERROR
Execution
Command
AT&D[<value>]
Parameter
<value> 0 TA ignores status on DTR.
1 ON->OFF on DTR: Change to Command mode with
remaining the connected call.
2 ON->OFF on DTR: Disconnect call, change to Command
mode. During state DTR = OFF is auto-answer off.
Reference
V.25ter
Note
2.2.30 AT&F Factory Defined Configuration
AT&F Factory Defined Configuration
Response
TA sets all current parameters to the manufacturer defined profile.
OK
Execution
Command
AT&F[<value>]
Parameter
<value> 0 Set all TA parameters to manufacturer defaults.
Reference
V.25ter
Note
Parameter impacted by &F command:
Command Parameter name Default value
ATE <echo> 0x01
ATQ <result> 0x00
ATV <format> 0x01
ATX <result> 0x04
AT+IFC <TA_by_TE> 0x00
AT+IFC <TE_by_TA> 0x00
ATS0 <num> 0x00
ATS3 <char> 0x0D
ATS4 <char> 0x0A
ATS5 <char> 0x08

ATS7 <time> 0x64
ATS8 <time> 0x02
ATS10 <time> 0x0E
AT+CRLP <ver> 0x00
AT+CRLP <T4> 0x07
AT+CRLP <iws> 0x61
AT+CRLP <mws> 0x61
AT+CRLP <T1> 0x48
AT+CRLP <N2> 0x06
AT+CPBS <storage> 0x53 0x4D 0x00
AT+CSMP <fo> 0x11
AT+CSMP <vp> 0x00
AT+CSMP <vp> 0x18
AT+CSMP <vp> 0x00
AT+CSMP <vp> 0x00
AT+CSMP <fo> 0x11
AT+CSMP <vp> 0x00
AT+CSMP <vp> 0x18
AT+CSMP <vp> 0x00
AT+CSMP <vp> 0x00
AT+CSMP <fo> 0x11
AT+CSMP <vp> 0x00
AT+CSMP <vp> 0x18
AT+CSMP <vp> 0x00
AT+CSMP <vp> 0x00
AT+CSMP <vp> 0x00..0x00
AT+CSMP <pid> 0x00
AT+CSMP <dcs> 0x00
AT+CR <mode> 0x00
AT+CSTA <type> 0x81
AT+CBST <speed> 0x05 0x02 0x00
AT+CBST <name> 0x01 0x00
AT+CBST <ce> 0x01
AT+CRC <mode> 0x00
AT+CMOD <mode> 0x00
AT+CMEE <n> 0x00
AT+CREG <n> 0x00
AT+CGREG <n> 0x00

AT+CSMS <service> 0x00
AT+CMGF <mode> 0x00
AT+CSDH <show> 0x00
AT+CSCS <chset> 0x00
AT+CLIR <n> 0x00
AT+CLIP <n> 0x00
AT+COLP <n> 0x00
2.2.31 AT&V Display Current Configuration
AT&V Display Current Configuration
Response
TA returns the current parameter setting.
<current configurations text>
OK
ERROR
Execution
Command
AT&V[<n>]
Parameter
<n> 0 Responses in numeric format
Reference
V.25ter
Note
2.2.32 AT&W Store Active Profile
AT&W Store Active Profile
Response
TA stores the current parameter setting in the user defined profile.
OK
ERROR
Execution
Command
AT&W[<n>]
Parameter
<n> 0 Store the current configuration in profile 0
1 Store the current configuration in profile 1
Reference
V.25ter
Note
The user defined profile is stored in non volatile memory.
Parameter stored by &W
Command Parameter name Displayedby &V
ATE <echo> Y
ATQ <result> Y
ATV <format> Y
ATX <result> Y

AT&C <behavior> Y
AT&D <behavior> Y
AT+IFC <TA_by_TE> Y
AT+IFC <TE_by_TA> Y
AT+FCLASS <class> Y
ATS0 <num> Y
ATS3 <char> Y
ATS4 <char> Y
ATS5 <char> Y
ATS7 <time> Y
ATS8 <time> Y
ATS10 <time> Y
2.2.33 AT+GCAP Request Complete TA Capabilities List
AT+GCAP Request Complete TA Capabilities List
Response
TA reports a list of additional capabilities.
+GCAP: list of supported <name>s
OK
Execution
Command
AT+GCAP
Parameter
<name> +CGSM GSM function is supported
+FCLASS FAX function is supported
Reference
V.25ter
Note
The command can be executed only when the SIM card is present.
2.2.34 AT+GMI Request Manufacturer Identification
AT+GMI Request Manufacturer Identification
Response
OK
Test Command
AT+GMI=?
Parameter
Execution
Command
AT+GMI
TA reports one or more lines of information text which permit the user to
identify the manufacturer.
SIMCOM_Ltd
OK
Reference
V.25ter
Note

2.2.35 AT+GMM Request TA Model Identification
AT+GMM Request TA Model Identification
Test Command
AT+GMM=?
Response
OK
identify the specific model of device.
<model>
OK
Execution
Command
AT+GMM
Parameter
<model> product model identification text
Reference
V.25ter
Note
2.2.36 AT+GMR Request TA Revision Identification of Software Release
AT+GMR Request TA Revision Identification of Software Release
Test Command
AT+GMR=?
Response
OK
identify the revision of software release.
Revision: <revision>
OK
Execution
Command
AT+GMR
Parameter
<revision> Revision of software release
Reference
V.25ter
Note
2.2.37 AT+GOI Request Global Object Identification
AT+GOI Request Global Object Identification
Test Command
AT+GOI=?
Response
OK
Execution
Command
AT+GOI
Response
identify the device, based on the ISO system for registering unique object
identifiers.
<Object Id>

OK
Parameter
<Object Id> identifier of device type
see X.208, 209 for the format of <Object Id>
Reference
V.25ter
Note
2.2.38 AT+GSN Request TA Serial Number Identification (IMEI)
AT+GSN Request TA Serial Number Identification(IMEI)
Test Command
AT+GSN=?
Response
OK
Response
TA reports the IMEI (international mobile equipment identifier) number in
information text which permit the user to identify the individual ME device.
<sn>
OK
Execution
Command
AT+GSN
Parameter
<sn> IMEI of the telephone(International Mobile station Equipment
Identity)
Reference
V.25ter
Note
The serial number (IMEI) is varied by individual ME device.
2.2.39 AT+ICF Set TE-TA Control Character Framing
AT+ICF Set TE-TA Control Character Framing
Response
+ICF: (list of supported <format>s),(list of supported <parity>s)
OK
Test Command
AT+ICF=?
Parameters
See Write Command
Response
+ICF: <format>,<parity>
OK
Read Command
AT+ICF?
Parameters
See Write Command
Write Command
AT+ICF=<forma
t>,[<parity>]
Response
This parameter setting determines the serial interface character framing
format and parity received by TA from TE.

OK
Parameters
<format> 1 8 data 0 parity 2 stop
2 8 data 1 parity 1 stop
<parity> 0 odd
1 even
3 space (0)
Reference
V.25ter
Note
The Command is applied for Command state;
In <format> parameter, "0 parity" means no parity;
The <parity> field is ignored if the <format> field specifies no parity
and string "+ICF: <format>,255" will be response to AT+ICF?
Command.
2.2.40 AT+IFC Set TE-TA Local Data Flow Control
AT+IFC Set TE-TA Local Data Flow Control
Response
+IFC: (list of supported <dce_by_dte>s),(list of supported
<dte_by_dce>s)
OK
Test Command
AT+IFC=?
Parameters
See Write Command
Response
+IFC: <dce_by_dte>,<dte_by_dce>
OK
Read Command
AT+IFC?
Parameters
See Write Command
Response
This parameter setting determines the data flow control on the serial
interface for data mode.
OK
Write Command
AT+IFC=<dce_b
y_dte>[,<dte_by
_dce>]
Parameters
<dce_by_dte> Specifies the method will be used by TE at receive of
data from TA
0 No flow control

1 Software flow control
2 Hardware flow control
<dte_by_dce> Specifies the method will be used by TA at receive of
data from TE
0 No flow control
1 Software flow control
2 Hardware flow control
Reference
V.25ter
Note
2.2.41 AT+IPR Set TE-TA Fixed Local Rate
AT+IPR Set TE-TA Fixed Local Rate
Response
+IPR: (),(list of supported <rate>s)
OK
Test Command
AT+IPR=?
Parameter
See Write Command
Response
+IPR: <rate>
OK
Read Command
AT+IPR?
Parameter
See Write Command
Response
This parameter setting determines the data rate of the TA on the serial
interface. The rate of Command takes effect following the issuance of any
result code associated with the current Command line.
OK
Write Command
AT+IPR=<rate>
Parameter
<rate> Baud rate per second
0 (Auto-bauding)
1200
2400
4800
9600
19200
38400
57600
115200

Reference
V.25ter
Note
Factory setting is AT+IPR=0（auto-bauding）.
2.2.41.1 Auto-bauding
Synchronization between DTE and DCE ensure that DTE and DCE are correctly synchronized and
the baud rate used by the DTE is detected by the DCE (= ME). To allow the baud rate to be
synchronized, simply issue an "AT" string. This is necessary when you start up the module while
auto-bauding is enabled. It is recommended to wait 3 to 5 seconds before sending the first AT
character. Otherwise undefined characters might be returned.
If you want to use auto-bauding and auto-answer at the same time, you can easily enable the
DTE-DCE synchronization, when you activate auto-bauding first and then configure the
auto-answer mode.
Restrictions on auto-bauding operation
The serial interface has to be operated at 8 data bits, no parity and 1 stop bit (factory
setting).
Only the strings "AT" or "At" (not "aT" or "at") can be detected when auto-bauding is
enabled.
AT+IPR=0 setting to auto-bauding will take effect after module resets. If user wants to
change DTE baud rate during module is running, i.e. from 57600 to 4800, DTR shall be
used to urge auto-bauding progress. DTR shall be pulled up to invalid state at least 2
seconds by DTE and then pulled down to valid state. The step will urge auto-bauding
progress and DCE will synchronize its baud rate after it receives data from the serial port.
Unsolicited Result Codes that may be issued before the ME detects the new baud rate (by
receiving the first AT Command string) will be sent at the previously detected baud rate.
The Unsolicited Result Codes "RDY" and so on are not indicated when you start up the ME
while auto-bauding is enabled.
It is not recommended to switch to auto-bauding from a baud rate that cannot be detected
by the auto-bauding mechanism (e.g. 300 baud). Responses to +IPR=0 and any commands
on the same line might be corrupted.
Auto-bauding and baud rate after restart
The most recently detected baud rate can not be stored when module is powered down.
2.2.42 AT+HVOIC Disconnect Voice Call Only
AT+HVOIC Disconnect Voice Call Only
Execution
Command
AT+HVOIC
Response
Disconnect existing voice call by local TE from Command line and
terminate call with existing PPP or CSD connection on.
OK
Reference
V.25ter
Note

3 AT Commands According to GSM07.07
3.1 Overview of AT Command According to GSM07.07
Command Description
AT+CACM ACCUMULATED CALL METER(ACM) RESET OR QUERY
AT+CAMM ACCUMULATED CALL METER MAXIMUM(ACM MAX) SET OR
QUERY
AT+CAOC ADVICE OF CHARGE
AT+CBST SELECT BEARER SERVICE TYPE
AT+CCFC CALL FORWARDING NUMBER AND CONDITIONS CONTROL
AT+CCWA CALL WAITING CONTROL
AT+CEER EXTENDED ERROR REPORT
AT+CGMI REQUEST MANUFACTURER IDENTIFICATION
AT+CGMM REQUEST MODEL IDENTIFICATION
AT+CGMR REQUEST TA REVISION IDENTIFICATION OF SOFTWARE
RELEASE
AT+CGSN REQUEST PRODUCT SERIAL NUMBER IDENTIFICATION
(IDENTICAL WITH +GSN)
AT+CSCS SELECT TE CHARACTER SET
AT+CSTA SELECT TYPE OF ADDRESS
AT+CHLD CALL HOLD AND MULTIPARTY
AT+CIMI REQUEST INTERNATIONAL MOBILE SUBSCRIBER IDENTITY
AT+CLCC LIST CURRENT CALLS OF ME
AT+CLCK FACILITY LOCK
AT+CLIP CALLING LINE IDENTIFICATION PRESENTATION
AT+CLIR CALLING LINE IDENTIFICATION RESTRICTION
AT+CMEE REPORT MOBILE EQUIPMENT ERROR
AT+COLP CONNECTED LINE IDENTIFICATION PRESENTATION
AT+COPS OPERATOR SELECTION
AT+CPAS PHONE ACTIVITY STATUS
AT+CPBF FIND PHONEBOOK ENTRIES
AT+CPBR READ CURRENT PHONEBOOK ENTRIES
AT+CPBS SELECT PHONEBOOK MEMORY STORAGE
AT+CPBW WRITE PHONEBOOK ENTRY
AT+CPIN ENTER PIN
AT+CPWD CHANGE PASSWORD
AT+CR SERVICE REPORTING CONTROL
AT+CRC SET CELLULAR RESULT CODES FOR INCOMING CALL
SIM300_ATC_V1.03 1 08.29.2008

INDICATION
AT+CREG NETWORK REGISTRATION
AT+CRLP SELECT RADIO LINK PROTOCOL PARAMETERS
AT+CRSM RESTRICTED SIM ACCESS
AT+CSQ SIGNAL QUALITY REPORT
AT+FCLASS FAX: SELECT, READ OR TEST SERVICE CLASS
AT+FMI FAX: REPORT MANUFACTURED ID
AT+FMM FAX: REPORT MODEL ID
AT+FMR FAX: REPORT REVISION ID
AT+VTD TONE DURATION
AT+VTS DTMF AND TONE GENERATION
AT+CMUX MULTIPLEXER CONTROL
AT+CNUM SUBSCRIBER NUMBER
AT+CPOL PREFERRED OPERATOR LIST
AT+COPN READ OPERATOR NAMES
AT+CFUN SET PHONE FUNCTIONALITY
AT+CCLK CLOCK
AT+CSIM GENERIC SIM ACCESS
AT+CALM ALERT SOUND MODE
AT+CALS ALERT SOUND SELECT
AT+CRSL RINGER SOUND LEVEL
AT+CLVL LOUD SPEAKER VOLUME LEVEL
AT+CMUT MUTE CONTROL
AT+CPUC PRICE PER UNIT AND CURRENCY TABLE
AT+CCWE CALL METER MAXIMUM EVENT
AT+CBC BATTERY CHARGE
AT+CUSD UNSTRUCTURED SUPPLEMENTARY SERVICE DATA
AT+CSSN SUPPLEMENTARY SERVICES NOTIFICATION
3.2 Detailed Descriptions of AT Command According to GSM07.07
3.2.1 AT+CACM Accumulated Call Meter (ACM) Reset or Query
AT+CACM Accumulated Call Meter(ACM) Reset or Query
Test Command
AT+CACM=?
Response
OK
Read Command
AT+CACM?
Response
TA returns the current value of ACM.

+CACM: <acm>
OK
If error is related to ME functionality:
+CME ERROR: <err>
Parameter
<acm> string type (string should be included in quotation marks);
three bytes of the current ACM value in hexa-decimal format
(e.g. "00001E" indicates decimal value 30)
000000 – FFFFFF
Response
TA resets the Advice of Charge related accumulated call meter (ACM)
value in SIM file EF (ACM). ACM contains the total number of home
units for both the current and preceding calls.
OK
+CME ERROR: <err>
Write Command
AT+CACM=<pa
sswd>
Parameter
<passwd> string type (string should be included in quotation marks):
SIM PIN2
Reference
GSM 07.07 [13]
Note
3.2.2 AT+CAMM Accumulated Call Meter Maximum (ACM max) Set or Query
AT+CAMM Accumulated Call Meter Maximum(ACM max) Set or Query
Test Command
AT+CAMM=?
Response
OK
Response
TA returns the current value of ACM max.
+CAMM: <acmmax>
OK
+CME ERROR: <err>
Read Command
AT+CAMM?
Parameters
See Write Command
Write Command
AT+CAMM=<ac
mmax>[,<passwd
Response
TA sets the Advice of Charge related accumulated call meter maximum
value in SIM file EF (ACM max). ACM max contains the maximum

number of home units allowed to be consumed by the subscriber.
OK
ERROR
+CME ERROR: <err>
>]
Parameters
<acmmax> string type (string should be included in quotation
marks); three bytes of the max. ACM value in
hex-decimal format (e.g. "00001E" indicates decimal
value 30)
000000 disable ACMmax feature
000001-FFFFFF
<passwd> string type (string should be included in quotation marks)
SIM PIN2
Reference
GSM 07.07 [13]
Note
3.2.3 AT+CAOC Advice of Charge
AT+CAOC Advice of Charge
Response
+CAOC: (list of supported <mode>s)
OK
Test Command
AT+CAOC=?
Parameters
See Write Command
Response
+CAOC: <mode>
OK
Read Command
AT+CAOC?
Parameters
See Write Command
Write Command
AT+CAOC=<mo
de>
Response
TA sets the Advice of Charge supplementary service function mode.
If <mode>=0, TA returns the current call meter value
+CAOC: <ccm>
OK
If <mode>=1, TA deactivates the unsolicited reporting of CCM value
OK
If <mode>=2, TA activates the unsolicited reporting of CCM value

OK
ERROR
+CME ERROR: <err>
Parameters
<mode> 0 Query CCM value
1 Deactivate the unsolicited reporting of CCM value
2 Activate the unsolicited reporting of CCM value
<ccm> String type (string should be included in quotation marks);
three bytes of the current CCM value in hex-decimal format
(e.g. "00001E" indicates decimal value 30); bytes are
similarly coded as ACMmax value in the SIM
000000-FFFFFF
Reference
GSM 07.07 [13]
Note
3.2.4 AT+CBST Select Bearer Service Type
AT+CBST Select Bearer Service Type
Response
+CBST: (list of supported <speed>s),(list of supported <name>s),(list of
supported <ce>s)
OK
Test Command
AT+CBST=?
Parameters
See Write Command
Response
+CBST: <speed>,<name>,<ce>
OK
Read Command
AT+CBST?
Parameters
See Write Command
Response
TA selects the bearer service <name> with data rate <speed>, and the
connection element <ce> to be used when data calls are originated.
OK
ERROR
Write Command
AT+CBST=<spee
d>[,<name>[,<ce
>]]
Parameters
<speed> 0 Auto-bauding (automatic selection of the speed; this

setting is possible in case of 3.1kHz modern and
non-transparent service)
7 9600 bps (V.32)
71 9600 bps (V.110 or X.31 flag stuffing)
Supported if UMTS_FTR is activated
<name> 0 Data circuit asynchronous (UDI or 3.1 kHz modem)
<ce> 1 Non-transparent
Reference
GSM 07.07 [14]
Note
GSM 02.02[1]: lists the allowed combinations of the sub parameters
It only supports the speed of 9600bps when in non-transparent mode.
3.2.5 AT+CCFC Call Forwarding Number and Conditions Control
AT+CCFC Call Forwarding Number and Conditions Control
Response
+CCFC: (list of supported <reason>s)
OK
Test Command
AT+CCFC=?
Parameter
See Write Command
Write Command
AT+CCFC =
<reason>,
<mode>
[, <number> [,
<type> [,<class>
[, <subaddr>
[,<satype>
[,time]]]]]]
Response
TA controls the call forwarding supplementary service. Registration,
erasure, activation, deactivation, and status query are supported.
Only ,<reads> and <mode> should be entered with mode (0-2,4)
If <mode>≠2 and Command successful
OK
If <mode>=2 and Command successful (only in connection with <reads> 0
–3)
For registered call forwarding numbers:
when <mode>=2 and command successful:
+CCFC: <status>,<class1>
[,<number>,<type>[,<subaddr>,<satype>[,<time>]]]
[<CR><LF>+CCFC: <status>,<class2>
[,<number>,<type>[,<subaddr>,<satype>[,<time>]]][…]
OK
If no call forwarding numbers are registered (and therefore all classes are
inactive):
+CCFC: <status>, <class>
OK
where <status>=0 and <class>=7
+CME ERROR: <err>

Parameters
<reason> 0 Unconditional
1 Mobile busy
2 No reply
3 Not reachable
4 All call forwarding
5 All conditional call forwarding
<mode> 0 Disable
1 Enable
2 Query status
3 Registration
4 Erasure
<number> string type (Phone number of forwarding address in format
specified by <type>)
<type> type of address
<subaddr> string type (subaddress of format specified by <satype>)
<satype> type of sub-address in integer
<class> 1 Voice (telephony)
2 Data (refers to all bearer services; with <mode>=2 this
may refer only to some bearer service if TA does not
support values 16, 32, 64 and 128)
4 Fax (facsimile services)
7 All classes
<time> 1..30 When "no reply" is enabled or queried, this gives the
time in seconds to wait before call is forwarded,
default value is 20.Supported only if it is multiples
of 5.
<status>
0 Not active
1 Active
Reference
GSM07.07
Note
3.2.6 AT+CCWA Call Waiting Control
AT+CCWA Call Waiting Control
Response
+CCWA: (list of supported <n>s)
OK
Test Command
AT+CCWA=?
Parameter
See Write Command
Read Command Response

+CCWA: <n>
OK
AT+CCWA?
Parameter
See Write Command
Response
TA controls the Call Waiting supplementary service. Activation,
deactivation and status query are supported.
If <mode>≠2 and Command successful
OK
If <mode>=2 and Command successful
+CCWA:<status>,<class1>[<CR><LF>+CCWA:<status>,<class2>[...]]
OK
ERROR
+CME ERROR: <err>
Note: <status>=0 should be returned only if service is not active for any
<class> i.e. +CCWA: 0, 7 will be returned in this case.
When mode=2, all active call waiting classes will be reported. In this mode
the Command is abortable by pressing any key.
Parameters
<n> 0 Disable presentation of an unsolicited result code
1 Enable presentation of an unsolicited result code
<mode> When <mode> parameter not given, network is not
interrogated
0 Disable
1 Enable
2 Query status
<class> is a sum of integers each representing a class of information
1 voice (telephony)
2 data (refers to all bearer services; with <mode>=2 this
4 fax (facsimile services)
7 default(1+2+4)
<status> 0 not active
1 enable
Write Command
AT+CCWA=<n>[,
<mode>[,<class>]]

Unsolicited result code
RING
+CCWA: <number>,<type>,<class>[,<alpha>]

Parameters
<number> String type (string should be included in quotation marks)
phone number of calling address in format specified by
<type>
<type> Type of address octet in integer format;
129 Unknown type (IDSN format number)
161 National number type (IDSN format)
145 International number type (ISDN format )
177 Network specific number (ISDN format)
<alpha> optional string type(string should be included in quotation
marks) alphanumeric representation of <number>
corresponding to the entry found in phone book.
Reference
G S M 0 7 . 0 7
Note
3.2.7AT+CEER Extended Error Report
AT+CEER Extended Error Report
Response
+CEER: (list of supported <n>s)
OK
Test Command
AT+CEER=?
Parameter
See Write Command
Response
+CEER: <n>
OK
Read Command
AT+CEER?
Parameter
See Write Command
Response
OK
Write Command
AT+CEER=<n>
Parameter
<n> 0 The reason for last call release as text code
1 The reason for last call release as number code
Execution
Command
AT+CEER
Response
TA returns an extended report of the reason for the last call release.
+CEER: <report>
OK

Parameter
<report> If AT+CEER=0, return <c>
<c> a string that represents the Cause
If AT+CEER=1, return
CauseSelect: <cs> Cause:<c>
<cs> number representing the CauseSelect
<c> number representing the Cause
Parameters
CauseSelect <cs> Cause <c>(number) <c>(string)
0 (No cause) 0 (No cause)
16 (Service provider) 0 (Unknown)
1 (Not Allowed)
2 (No cause)
6 (Wrong parameter)
9 (Network access not allowed)
20 (all call instances are used)
21 (ACM over ACM Max)
22 (invalid AOC element)
23 (SIM increase not allowed)
24 (switch off)
25 (Unknown call id)
28 (barred)
65 (Local cause) 1 (state error)
2 (no call entity)
3 (wrong TI)
6 (DTMF buffer overflow)
7 (call disconnected)
17 (No cell available)
32 (Local rejection)
33 (PLMN not allowed)
34 (emergency call not possible)
35 (authentication rejected)
36 (network rejection)
37 (LA not allowed)
38 (Local timeout)

39 (server congestion)
40 (local data rejection)
48 (failed replace PDP context)
66 (MM network cause) See [24.008]
67 (CC network cause) See [24.008]
69 (RP cause) See [24.008]
71 (SIM cause) 0 (Unknown problem)
1 (Memory problem)
2 (File Id not found)
6 (Increase problem)
7 (Technical problem)
11 (Command not allowed)
15 (SIM card out)
73 (SM cause) See [24.008]
Reference
GSM 07.07 [13]
Note
3.2.8 AT+CGMI Request Manufacturer Identification
AT+CGMI Request Manufacturer Identification
Test Command
AT+CGMI=?
Response
OK
Response
TA returns manufacturer identification text.
<manufacturer>
OK
Execution
Command
AT+CGMI
Parameter
<manufacturer> the ID of manufacturer
Reference
GSM 07.07 [13]
Note
3.2.9 AT+CGMM Request Model Identification
AT+CGMM Request Model Identification
Test Command Response

AT+CGMM=? OK
Response
TA returns product model identification text.
<model>
OK
Execution
Command
AT+CGMM
Parameter
<model> product model identification text
Reference
GSM 07.07 [13]
Note
3.2.10 AT+CGMR Request TA Revision Identification of Software Release
AT+CGMR Request TA Revision Identification of Software Release
Test Command
AT+CGMR=?
Response
OK
Response
TA returns product software version identification text.
Revision: <revision>
OK
Execution
Command
AT+CGMR
Parameter
<revision> product software version identification text
Reference
GSM 07.07 [13]
Note
3.2.11 AT+CGSN Request Product Serial Number Identification (Identical with +GSN)
AT+CGSN Request Product Serial Number Identification (Identical with +GSN)
Test Command
AT+CGSN=?
Response
OK
Response
see +GSN
<sn>
OK
Execution
Command
AT+CGSN
Parameter
<sn> International mobile equipment identity (IMEI)
Reference
GSM 07.07 [13]
Note

3.2.12 AT+CSCS Select TE Character Set
AT+CSCS Select TE Character Set
Response
+CSCS: (list of supported <chset>s)
OK
Test Command
AT+CSCS=?
Parameter
<chset> "GSM" GSM 7 bit default alphabet (3GPP TS 23.038);
"UCS2" 16-bit universal multiple-octet coded character set
(ISO/IEC10646); UCS2 character strings are
converted to hexadecimal numbers from 0000 to
FFFF; e.g. "004100620063" equals three 16-bit
characters with decimal values 65, 98 and 99
"IRA" International reference alphabet (ITU-T T.50)
"HEX" Character strings consist only of hexadecimal
numbers from 00 to FF;
"PCCP" PC character set Code
"PCDN" PC Danish/Norwegian character set
"8859-1" ISO 8859 Latin 1 character set
Response
+CSCS: <chset>
OK
Read Command
AT+CSCS?
Parameter
See Test Command
Response
Sets which character set <chset> are used by the TE. The TA can then
convert character strings correctly between the TE and ME character sets.
OK
+CME ERROR: <err>
Write Command
AT+CSCS=<chse
t>
Parameter
See Test Command
Reference
GSM 07.07 [13]
Note

3.2.13 AT+CSTA Select Type of Address
AT+CSTA Select Type of Address
Response
+CSTA: (list of supported <type>s)
OK
Test Command
AT+CSTA=?
Parameter
See Write Command
Response
+CSTA: <type>
OK
Read Command
AT+CSTA?
Parameter
<type> Current address type setting.
Response
OK
If <type> is not in the parameter range:
ERROR
Write Command
AT+CSTA=<type
>
Parameter
Reference
GSM 07.07 [13]
Note
The ATD Command overrides this setting when a number is dialed.
3.2.14 AT+CHLD Call Hold and Multiparty
AT+CHLD Call Hold and Multiparty
Response
+CHLD: (list of supported <n>s)
OK
Test Command
AT+CHLD=?
Parameter
See Write Command
Write Command
AT+CHLD=<n>
Response
TA controls the supplementary services Call Hold, Multiparty and Explicit

Call Transfer. Calls can be put on hold, recovered, released, added to
conversation, and transferred.
Note These supplementary services are only applicable to tele service 11
(Speech: Telephony).
OK
+CME ERROR: <err>
Parameter
<n> 0 Releases all held calls or sets User Determined User Busy
(UDUB) for a waiting call
1 Releases all active calls (if any exist) and accepts the other
(held or waiting) call.
1x Releases a specific active call x
2 Place all active calls on hold (if any) and accept the other
(held or waiting) call.
2x Places all active calls on hold except call X with which
communication shall be supported.
3 Adds a held call to the conversation.
4 Connects the two calls and disconnects the subscriber from
both calls(ECT)
6 Swap operation(retrieves the held call and holds the active
call). Not applicable for calls engaged in a multiparty
operation(+CME ERROR returned)
6x Retrieves the specified held call x. Not applicable for calls
engaged in a multiparty operation (+CME ERROR
returned)
7x Holds the specified active call x. Not applicable for calls
engaged in a multiparty operation (+CME ERROR
returned)
8x Releases the specified call x (whatever its state).
9x Aborts MO speech call x setup without releasing other
calls. Possible if OK result code is sent before call is
connected: allowed if *PSCSSC mode = enabled and
+COLP = disabled.
Reference Note
3.2.15 AT+CIMI Request International Mobile Subscriber Identity
AT+CIMI Request International Mobile Subscriber Identity
Test Command
AT+CIMI=?
Response
OK

Response
TA returns <IMSI>for identifying the individual SIM which is attached to
ME.
<IMSI>
OK
+CME ERROR: <err>
Execution
Command
AT+CIMI
Parameter
<IMSI> International Mobile Subscriber Identity (string without
double quotes)
Reference
GSM 07.07 [13]
Note
3.2.16 AT+CLCC List Current Calls of ME
AT+CLCC List Current Calls of ME
Response
+CLCC: (0,1)
OK
Test Command
AT+CLCC=?
Parameters
See Write Command
Response
+CLCC: <n>
OK
Read Command
AT+CLCC?
Parameters
See Write Command
Response
OK
Write Command
AT+CLCC=<n>
Parameter
<n> 0 Don’t report a list of current calls of ME automatically
when the current call status changes.
1 Report a list of current calls of ME automatically when the
current call status changes.

Response
TA returns a list of current calls of ME.
Note: If Command succeeds but no calls are available, no information
response is sent to TE.
[+CLCC: <id1>,<dir>,<stat>,<mode>,<mpty>[,<number>,<type
>,<alphaID>][<CR><LF>+CLCC:
<id2>,<dir>,<stat>,<mode>,<mpty>
[,<number>,<type>,<alphaID>][...]]]
OK
+CME ERROR: <err>
Execution
Command
AT+CLCC
Parameters
<idx> 1..7 Call identification number
This number can be used in +CHLD command operations
<dir> 0 Mobile originated (MO) call
1 Mobile terminated (MT) call
<stat> State of the call:
0 active
1 held
2 dialing (MO call)
3 alerting (MO call)
4 incoming (MT call)
5 waiting (MT call)
6 disconnect
<mode> Bearer/tele service:
0 voice
1 data
2 fax
<mpty> 0 Call is not one of multiparty (conference) call parties
1 Call is one of multiparty (conference) call parties
<number> String type(string should be included in quotation marks)
phone number in format specified by <type>.
<type> Type of address
<alphaId> String type(string should be included in quotation marks)
alphanumeric representation of <number> corresponding
to the entry found in phone book.
Reference
GSM 07.07
[13][14]
Note

3.2.17 AT+CLCK Facility Lock
AT+CLCK Facility Lock
Response
+CLCK: (list of supported <fac>s)
OK
Test Command
AT+CLCK=?
Parameter
See Write Command
Response
This Command is used to lock, unlock or interrogate a ME or a network
facility <fac>. Password is normally needed to do such actions. When
querying the status of a network service (<mode>=2) the response line for
‘not active’ case (<status>=0) should be returned only if service is not
active for any <class>.
If <mode>≠2 and Command is successful
OK
If <mode>=2 and Command is successful
+CLCK: <status>[,<class1>[<CR><LF>+CLCK:
<status>,<class2>[…]]
OK
+CME ERROR: <err>
Write Command
AT+CLCK=
<fac>,<mode>
[,<passwd>
[,<class>]]
Parameters
<fac>
"AO" BAOC (Barr All Outgoing Calls)
"OI" BOIC (Barr Outgoing International Calls)
"OX" BOIC-exHC (Barr Outgoing International Calls
except to Home Country)
"AI" BAIC (Barr All Incoming Calls)
"IR" BIC-Roam (Barr Incoming Calls when Roaming
outside the home country)
"AB" All Barring services
"AG" All out oing barring services
"AC" All in Coming barring services
"FD" SIM card or active application in the UICC (GSM or
USIM) fixed dialling memory feature (if PIN2
authentication has not been done during the current
session, PIN2 is required as <passwd>)
"SC" SIM (lock SIM/UICC card) (SIM/UICC asks
password in MT power-up and when this lock
command issued) Correspond to PIN1 code.

"PN" Network Personalization, Correspond to NCK code
"PU" Network subset Personalization
Correspond to NSCK code
"PP" Service Provider Personalization
Correspond to SPCK code
<mode> 0 unlock
1 lock
2 query status
<passwd> String type (Shall be the same as password specified for the
facility from the MT user interface or with command Change
Password +CPWD)
<class> 1 voice (telephony)
2 data refers to all bearer services; with <mode>=2 this
4 fax (facsimile services)
7 all classes
<status> 0 Not active
1 Active
Reference
GSM 07.07 [14]
Note
CME errors if SIM not inserted or PIN is not entered.
3.2.18 AT+CLIP Calling Line Identification Presentation
AT+CLIP Calling Line Identification Presentation
Response
+CLIP: (list of supported <n>s)
OK
Test Command
AT+CLIP=?
Parameter
See Write Command
Response
+CLIP: <n>, <m>
OK
+CME ERROR: <err>
Read Command
AT+CLIP?
Parameters
See Write Command
Write Command
AT+CLIP=<n>
Response
TA enables or disables the presentation of the CLI at the TE. It has no
effect on the execution of the supplementary service CLIP in the network.
OK

+CME ERROR: <err>
Parameters
<n> 0 Disable +CLIP notification.
1 Enable +CLIP notification.
<m> 0 CLIP not provisioned
1 CLIP provisioned
2 unknown (e.g. no network, etc.)
Unsolicited Result Code
When the presentation of the CLI at the TE is enabled (and calling
subscriber allows), an unsolicited result code is returned after every RING
(or +CRING: <type>) at a mobile terminating call.
+CLIP: <number>,<type> [,<subaddr>,<satype>,<alphaId>,<CLI
validity>]
Parameters
<number> String type (string should be included in quotation marks)
phone number of calling address in format specified by
<type>
129 Unknown type(IDSN format number)
161 National number type(IDSN format)
145 International number type(ISDN format )
177 Network specific number(ISDN format)
<subaddr> string type (subaddress of format specified by <satype>)
<satype> Integer type(type of subaddress)
<alphaId> string type (string should be included in quotation marks)
to the entry found in phone book
<CLI validity> 0 CLI valid
1 CLI has been withheld by the originator
2 CLI is not available due to interworking problems
or limitations of originating network
Reference Note
3.2.19 AT+CLIR Calling Line Identification Restriction
AT+CLIR Calling Line Identification Restriction
Test Command
AT+CLIR=?
Response
+CLIR: (list of supported <n>s)
OK

Parameter
See Write Command
Response
+CLIR: <n>, <m>
OK
+CME ERROR: <err>
Read Command
AT+CLIR?
Parameters
See Write Command
Response
TA restricts or enables the presentation of the CLI to the called party when
originating a call.
The Command overrides the CLIR subscription (default is restricted or
allowed) when temporary mode is provisioned as a default adjustment for
all following outgoing calls. This adjustment can be revoked by using the
opposite Command.
OK
+CME ERROR: <err>
Write Command
AT+CLIR=<n>
Parameters
<n> (parameter sets the adjustment for outgoing calls):
0 presentation indicator is used according to the subscription of
the CLIR service.
1 CLIR invocation
2 CLIR suppression
<m> (parameter shows the subscriber CLIR service status in the
network):
0 CLIR not provisioned
1 CLIR provisioned in permanent mode
2 unknown (e.g. no network, etc.)
3 CLIR temporary mode presentation restricted
4 CLIR temporary mode presentation allowed
Reference Note
3.2.20 AT+CMEE Report Mobile Equipment Error
AT+CMEE Report Mobile Equipment Error
Test Command
AT+CMEE=?
Response
+CMEE: (list of supported <n>s)

OK
Parameter
See Write Command
Response
+CMEE: <n>
OK
Read Command
AT+CMEE?
Parameter
See Write Command
Response
TA disables or enables the use of result code +CME ERROR: <err> as an
indication of an error relating to the functionality of the ME.
OK
+CME ERROR:<err>
Write Command
AT+CMEE=<n>
Parameter
<n> 0 Disable +CME ERROR: <err> result code and use ERROR
instead.
1 Enable +CME ERROR: <err> result code and use numeric
<err>
2 Enable +CME ERROR: <err> result code and use verbose
<err> values
Reference
GSM 07.07 [13]
Note
3.2.21 AT+COLP Connected Line Identification Presentation
AT+COLP Connected Line Identification Presentation
Response
+COLP: (list of supported <n>s)
OK
Test Command
AT+COLP=?
Parameter
See Write Command
Response
+COLP: <n>,<m>
OK
+CME ERROR: <err>
Read Command
AT+COLP?
Parameters
See Write Command

Response
TA enables or disables the presentation of the COL (Connected Line) at the
TE for a mobile originated call. It has no effect on the execution of the
supplementary service COLR in the network.
Intermediate result code is returned from TA to TE before any +CR or
V.25ter responses.
OK
+CME ERROR: <err>
Parameters
<n> (parameter sets/shows the result code presentation status in the
TA):
0 Disable +COLP notification
1 Enable +COLP notification
<m> (parameter shows the subscriber COLP service status in the
network):
0 COLP not provisioned
1 COLP provisioned
2 Unknown (e.g. no network, etc.)
Intermediate result code
When enabled (and called subscriber allows), an intermediate result code is
returned before any +CR or V.25ter responses:
+COLP: <number>,<type>[,<subaddr>,<satype> ,<alphaId>]
Write Command
AT+COLP=<n>
Parameters
<number> string type (string should be included in quotation marks)
phone number of format specified by <type>
<subaddr> string type (string should be included in quotation marks)
sub address of format specified by <satype>
<satype> Type of sub address octet in integer format (refer GSM
04.08 [8] sub clause 10.5.4.8)
<alphaId> string type (string should be included in quotation marks)
to the entry found in phone book.
Reference Note

3.2.22 AT+COPS Operator Selection
AT+COPS Operator Selection
Response
TA returns a list of quadruplets, each representing an operator present in
the network. Any of the formats may be unavailable and should then be an
empty field. The list of operators shall be in order: home network,
networks referenced in SIM, and other networks.
+COPS: (list of supported<stat>, long alphanumeric <oper>, short
alphanumeric <oper>, numeric <oper>)s [,,(list of supported
<mode>s),(list of supported <format>s)]
OK
+CME ERROR: <err>
Test Command
AT+COPS=?
Parameters
See Write Command
Response
TA returns the current mode and the currently selected operator. If no
operator is selected, <format> and <oper> are omitted.
+COPS: <mode>[,<format>, <oper>]
OK
+CME ERROR: <err>
Read Command
AT+COPS?
Parameters
See Write Command
Response
TA forces an attempt to select and register the GSM network operator. If
the selected operator is not available, no other operator shall be selected
(except <mode>=4). The selected operator name format shall apply to
further read commands (+COPS?).
OK
+CME ERROR: <err>
Write Command
AT+COPS =
<mode>,
[<format>[,<oper
>]]
Parameters
<stat> 0 unknown
1 operator available
2 operator current
3 operator forbidden
<oper> Refer to [27.007]
operator in format as per <format>

<mode> 0 automatic mode; <oper> field is ignored
1 manual (<oper> field shall be present, and <AcT>
optionally)
4 manual/automatic (<oper> field shall be present); if
manual selection fails, automatic mode (<mode>=0) is
entered
<format> 0 long format alphanumeric <oper>
1 short format alphanumeric <oper>
2 numeric <oper>; GSM Location Area Identification
number
Reference
GSM 07.07 [14]
Note
3.2.23 AT+CPAS Phone Activity Status
AT+CPAS Phone Activity Status
Response
+CPAS: (list of supported <pas>s)
OK
Test Command
AT+CPAS=?
Parameter
See Execution Command
Response
TA returns the activity status of ME.
+CPAS: <pas>
OK
+CME ERROR: <err>
Execution
Command
AT+CPAS
Parameter
<pas> 0 Ready (MT allows commands from TA/TE)
2 Unknown (MT is not guaranteed to respond to
instructions)
3 Ringing (MT is ready for commands from TA/TE, but the
ringer is active)
4 Call in progress (MT is ready for commands from TA/TE,
but a call is in progress)
Reference
GSM 07.07 [13]
Note
3.2.24 AT+CPBF Find Phonebook Entries
AT+CPBF Find Phonebook Entries

+CPBF: maximum length of field <nlength>,maximum length of field
<tlength>
OK
+CME ERROR: <err>
AT+CPBF=?
Parameters
See Write Command
Response
TA returns phone book entries (from the current phone book memory
storage selected with +CPBS) which contains alphanumeric string
<findtext>.
[+CPBF:<index1>,<number>,<type>,<text>][----]
<CR><LF>[+CBPF:<index2>,<number>,<type>,<text>]
OK
Write Command
AT+CPBF=[<find
text>]
Parameters
<findtext> string type(string should be included in quotation marks)
field of maximum length <tlength> in current TE character
set specified by +CSCS.
<index1> integer type values in the range of location numbers of
phone book memory
<index2> integer type values in the range of location numbers of
phone book memory
<number> string type(string should be included in quotation marks)
phone number of format <type>
<type> type of address octet in integer format ;
<text> string type (string should be included in quotation marks)
field of maximum length <tlength> in current TE character
set specified by +CSCS.
<nlength> integer type value indicating the maximum length of field
<number>
<tlength> integer type value indicating the maximum length of field
<text>
Reference
GSM 07.07 [13]
Note

3.2.25 AT+CPBR Read Current Phonebook Entries
AT+CPBR Read Current Phonebook Entries
Response
TA returns location range supported by the current storage as a compound
value and the maximum lengths of <number> and <text> fields.
+CPBR: (list of supported <index>s), <nlength>, <tlength>
OK
Test Command
AT+CPBR=?
Parameters
<index> location number
<nlength> max. length of phone number
<tlength> max. length of text for number
Response
TA returns phone book entries in location number range <index1>...
<index2> from the current phone book memory storage selected with
+CPBS. If <index2> is left out, only location <index1> is returned.
+CPBR:<index1>,<number>,<type>,<text>[<CR><LF>+CPBR: .....
<CR><LF>+CPBR: <index2>, <number>, <type>, <text>]
OK
Write Command
AT+CPBR=
<index1>
[, <index2>]
Parameters
<index1> read as of this location number
<index2> read to this location number
<number> phone number
<type> type of number
<text> text for phone number in current TE character set specified
by +CSCS.
Reference
GSM 07.07 [13]
Note
3.2.26 AT+CPBS Select Phonebook Memory Storage
AT+CPBS Select Phonebook Memory Storage
Response
+CPBS: (list of supported <storage>s)
OK
Test Command
AT+CPBS=?
Parameter
See Write Command
Read Command
AT+CPBS?
Response
+CPBS: <storage>[,<used>,<total>]

OK
Parameters
See Write Command
Response
TA selects current phone book memory storage, which is used by other
phone book commands.
OK
Write Command
AT+CPBS=<stora
ge>
Parameters
<storage> "DC" ME dialed calls list(+CPBW may not be applicable
for this storage)(same as LD)
"EN" SIM (or MT) emergency number (+CPBW is not
be applicable for this storage)
"FD" SIM fix dialing-phone book. If a SIM card is
present or if a UICC with an active GSM
application is present, the information in EFFDN
under DFTelecom is selected
"MC" MT missed (unanswered received) calls list
(+CPBW may not be applicable for this storage)
"ON" SIM (or MT) own numbers (MSISDNs) list
(reading of this storage may be available through
+CNUM also). When storing information in the
SIM/UICC, if a SIM card is present or if a UICC
with an active GSM application is present, the
information in EFMSISDN under DFTelecom is
selected.
"RC" MT received calls list (+CPBW may not be
applicable for this storage)
"SM" SIM/UICC phonebook. If a SIM card is present or
if a UICC with an active GSM application is present, the
EFADN under DFTelecom is selected.
"LA" Last Number All list (LND/LNM/LNR)
"ME" ME phonebook
"BN" SIM barred dialed number
"SD" SIM service dial number
"VM" SIM voice mailbox
"LD" SIM last-dialing-phone book
<used> integer type value indicating the total number of used
locations in selected memory
<total> integer type value indicating the total number of locations
in selected memory
Reference
GSM 07.07 [13]
Note

3.2.27 AT+CPBW Write Phonebook Entry
AT+CPBW Write Phonebook Entry
Response
TA returns location range supported by the current storage, the maximum
length of <number> field, supported number formats of the storage, and
the maximum length of <text> field.
+CPBW: (list of supported <index>s), <nlength>, (list of supported
<type>s), <tlength>
OK
Test Command
AT+CPBW=?
Parameters
See Write Command
Response
TA writes phone book entry in location number <index> in the current
phone book memory storage selected with +CPBS. Entry fields written are
phone number <number> (in the format <type>) and text <text> associated
with the number. If those fields are omitted, phone book entry is deleted. If
<index> is left out, but <number> is given, entry is written to the first free
location in the phone book.
OK
Write Command
AT+CPBW=
<index>
[, <number>,
[<type>, [<text>]]]
Parameters
<nlength> Max length of phone number
<tlength> Max length of text for number
<index> Location number
<number> Phone number
<type> Type of number;
129 National number type (IDSN format
<text> String type(string should be included in quotation marks):
text for phone number in current TE character set specified
by +CSCS.
Note: The following characters in <text> must be entered via the
escape sequence:
GSM char. Seq. Seq.(hex) Note
5C 5C 35 43 (backslash)
" 22 5C 32 32 (string delimiter)
BSP 08 5C 30 38 (backspace)
NULL 00 5C 30 30 (GSM null)
‘0’ (GSM null) may cause problems for application layer

software when reading string lengths.
Reference
GSM 07.07 [13]
Note
3.2.28 AT+CPIN Enter PIN
AT+CPIN Enter PIN
Test Command
AT+CPIN=?
Response
OK
Response
TA returns an alphanumeric string indicating whether some password is
required or not.
+CPIN: <code>
OK
Read Command
AT+CPIN?
Parameter
<code>
READY MT is not pending for any password
SIM PIN MT is waiting SIM PIN to be given
SIM PUK MT is waiting for SIM PUK to be given
PH_SIM PIN ME is waiting for phone to SIM card (antitheft)
PH_SIM PUK ME is waiting for SIM PUK (antitheft)
SIM PIN2 PIN2, e.g. for editing the FDN book possible
only if preceding Command was acknowledged
with +CME ERROR:17
SIM PUK2 possible only if preceding Command was
acknowledged with error +CME ERROR: 18.
Response
TA stores a password which is necessary before it can be operated (SIM
PIN, SIM PUK, PH-SIM PIN, etc.).
If the PIN required is SIM PUK or SIM PUK2, the second pin is required.
This second pin, <new pin>, is used to replace the old pin in the SIM.
OK
+CME ERROR: <err>
Write Command
AT+CPIN=<pin>
[, <new pin>]
Parameters
<pin> string type; password
<new pin> string type; If the PIN required is SIM PUK or SIMPUK2:
new password
Reference Note

GSM 07.07 [13]
3.2.29 AT+CPWD Change Password
AT+CPWD Change Password
Response
TA returns a list of pairs which present the available facilities and the
maximum length of their password.
+CPWD: (list of supported <fac>s, list of supported <pwdlength>s)
OK
Test Command
AT+CPWD=?
Parameters
<fac> see Write Command
<pwdlength> integer max. length of password
Response
TA sets a new password for the facility lock function.
OK
Write Command
AT+CPWD =
<fac>, <oldpwd>,
<newpwd>
Parameters
<fac>
"AO" BAOC (Barr All Outgoing Calls)
"OI" BOIC (Barr Outgoing International Calls)
"OX" BOIC-exHC (Barr Outgoing International Calls
except to Home Country)
"AI" BAIC (Barr All Incoming Calls)
"IR" BIC-Roam (Barr Incoming Calls when Roaming
outside the home country)
"AB" all Barring services
"P2" SIM PIN2
"SC" SIM (lock SIM/UICC card) (SIM/UICC asks password
in MT power-up and when this lock command
issued) Correspond to PIN1 code.
<oldpwd> string type (string should be included in quotation marks):
password specified for the facility from the user interface
or with Command. If an old password has not yet been
set, <oldpwd> is not to enter.
<newpwd> string type (string should be included in quotation marks):
new password
Reference
GSM 07.07 [13]
Note

3.2.30 AT+CR Service Reporting Control
AT+CR Service Reporting Control
Response
+CR: (list of supported <mode>s)
OK
Test Command
AT+CR=?
Parameter
See Write Command
Response
+CR: <mode>
OK
Read Command
AT+CR?
Parameter
See Write Command
Response
TA controls whether or not intermediate result code +CR: <serv> is
returned from the TA to the TE at a call set up.
OK
Parameter
<mode> 0 Disable
1 Enable
Intermediate result code
If enabled, an intermediate result code is transmitted at the point during
connect negotiation at which the TA has determined which speed and
quality of service will be used, before any error control or data
compression reports are transmitted, and before any final result code (e.g.
CONNECT) is transmitted.
+CR:<serv>
Write Command
AT+CR=<mode>
Parameters
<serv> ASYNC asynchronous transparent
SYNC synchronous transparent
REL ASYNC asynchronous non-transparent
REL SYNC synchronous non-transparent
GPRS for GPRS
Reference
GSM 07.07 [13]
Note
3.2.31 AT+CRC Set Cellular Result Codes for Incoming Call Indication
AT+CRC Set Cellular Result Codes for Incoming Call Indication

+CRC: (list of supported <mode>s)
OK
AT+CRC=?
Parameter
See Write Command
Response
+CRC: <mode>
OK
Read Command
AT+CRC?
Parameter
See Write Command
Response
TA controls whether or not the extended format of incoming call
indication is used.
OK
Parameter
<mode> 0 Disable extended format
1 Enable extended format
When enabled, an incoming call is indicated to the TE with unsolicited
result code +CRING: <type> instead of the normal RING.
Write Command
AT+CRC=<mode
>
Parameter
<type> ASYNC asynchronous transparent
SYNC synchronous transparent
REL ASYNC asynchronous non-transparent
REL SYNC synchronous non-transparent
FAX facsimile
VOICE voice
Reference
GSM 07.07 [13]
Note
3.2.32 AT+CREG Network Registration
AT+CREG Network Registration
Response
+CREG: (list of supported <n>s)
OK
Test Command
AT+CREG=?
Parameter
See Write Command

Read Command
AT+CREG?
Response
TA returns the status of result code presentation and an integer <stat>
which shows whether the network has currently indicated the registration
of the ME. Location information elements <lac> and <ci> are returned
only when <n>=2 and ME is registered in the network.
+CREG: <n>,<stat>[,<lac>,<ci>]
OK
+CME ERROR: <err>
Response
TA controls the presentation of an unsolicited result code +CREG: <stat>
when <n>=1 and there is a change in the ME network registration status.
OK
Parameters
<n> 0 Disable network registration unsolicited result code
1 Enable network registration unsolicited result code
+CREG: <stat>
2 Enable network registration unsolicited result code with
location information +CREG: <stat>[,<lac>,<ci>]
<stat> 0 Not registered, MT is not currently searching a new
operator to register to
1 Registered, home network
2 Not registered, but MT is currently searching a new
3 Registration denied
4 Unknown
5 Registered, roaming
<lac> String type (string should be included in quotation marks);
two byte location area code in hexadecimal format
<ci> String type (string should be included in quotation marks);
two byte cell ID in hexadecimal format
If <n>=1 and there is a change in the MT network registration status
+CREG: <stat>
If <n>=2 and there is a change in the MT network registration status or a
change of the network cell:
+CREG: <stat>[,<lac>,<ci>]
Write Command
AT+CREG=[<n>
]
Parameters
See Write Command
Reference
GSM 07.07 [13]
Note

3.2.33 AT+CRLP Select Radio Link Protocol Parameters
AT+CRLP Select Radio Link Protocol Parameters
Response
TA returns values supported. RLP versions 0 and 1 share the same
parameter set. TA returns only one line for this set (where <verx> is not
present).
+CRLP: (list of supported <iws>s),(list of supported <mws>s),(list of
supported <T1>s),(list of supported <N2>s),(list of supported
<ver1>s),(list of supported <T4>s)
OK
Test Command
AT+CRLP=?
Parameters
See Write Command
Response
TA returns current settings for RLP version. RLP versions 0 and 1 share
the same parameter set. TA returns only one line for this set (where
<verx> is not present).
+CRLP: <iws>,<mws>,<T1>,<N2>,<ver1>,<T4>
OK
Read Command
AT+CRLP?
Parameters
See Write Command
Response
TA sets radio link protocol (RLP) parameters used when non-transparent
data calls are setup.
OK
Write Command
AT+CRLP=<iws
>[,<mws>[,<T1>[
,<N2>[,<ver>[,<T
4>]]]]] Parameters
<iws> 0-61 Interworking window size (IWF to MS)
<mws> 0-61 Mobile window size(MS to IWF)
<T1> 44-255 Acknowledgment timer T1 in 10 ms units
<N2> 1-255 Retransmission attempts N2
<verx> 0 RLP version number
<T4> 7 Re-sequencing period in integer format, in units of 10 ms.
Reference
GSM 07.07 [13]
Note
3.2.34 AT+CRSM Restricted SIM Access
AT+CRSM Restricted SIM Access
Test Command
AT+CRSM=?
Response
OK

Response
+CRSM: <sw1>, <sw2> [,<response>]
OK
ERROR
+CME ERROR: <err>
Write Command
AT+CRSM=<Co
mmand>[,<fileId
>[,<P1>,<P2>,<P
3>[,<data>]]]
Parameters
<Command>
176 READ BINARY
178 READ RECORD
192 GET RESPONSE
214 UPDATE BINARY
220 UPDATE RECORD
242 STATUS
All other values are reserved; refer GSM 11.11.
<fileId> integer type; this is the identifier for an elementary data file on
SIM. Mandatory for every Command except STATUS
<P1>,<P2>,<P3> integer type, range 0 – 255
Parameters to be passed on by the ME to the SIM; refer GSM
11.11.
<data> information which shall be written to the SIM (hex-decimal
character format)
<sw1>, <sw2> integer type, range 0 - 255
Status information from the SIM about the execution
of the actual Command. These parameters are delivered to the
TE in both cases, on successful or failed execution of the
Command; refer GSM 11.11.
<response> response of a successful completion of the Command
previously issued (hexadecimal character format)
Reference
GSM 07.07
GSM 11.11
Note
3.2.35 AT+CSQ Signal Quality Report
AT+CSQ Signal Quality Report
Test Command
AT+CSQ=?
Response
+CSQ: (list of supported <rssi>s),(list of supported <ber>s)
OK
Execution
Command
AT+CSQ
Response
+CSQ: <rssi>,<ber>

OK
+CME ERROR: <err>
Execution Command returns received signal strength indication <rssi>
and channel bit error rate <ber> from the ME. Test Command returns
values supported by the TA.
Parameters
<rssi>
0 -115 dBm or less
1 -111 dBm
2...30 -110... -54 dBm
31 -52 dBm or greater
99 not known or not detectable
<ber> (in percent):
0...7 As RXQUAL values in the table in GSM 05.08 [20]
subclause 7.2.4
99 Not known or not detectable
Reference
GSM 07.07 [13]
Note
3.2.36 AT+FCLASS FAX: Select, Read or Test Service Class
AT+FCLASS FAX: Select, Read or Test Service Class
Response
+FCLASS: (list of supported <class>s)
OK
Test Command
AT+FCLASS=?
Parameter
See Write Command
Response
+FCLASS: <class>
OK
Read Command
AT+FCLASS?
Parameter
See Write Command
Response
TA sets a particular mode of operation (data fax). This causes the TA to
process information in a manner suitable for that type of information
OK
Write Command
AT+FCLASS=
<class>
Parameter
<n> 0 data

1 fax class 1 (TIA-578-A)
Reference
GSM 07.07 [13]
Note
3.2.37 AT+FMI FAX: Report Manufactured ID
AT+FMI FAX: Report Manufactured ID
Test Command
AT+FMI =?
Response
OK
Response
identify the manufacturer.
<manufacturer Id>
OK
Execution
Command
AT+FMI
Parameter
<manufacturer Id> the ID of manufacturer
Reference
EIA/TIA-578-D
Note
3.2.38 AT+FMM FAX: Report Model ID
AT+FMM FAX: Report Model ID
Test Command
AT+FMM =?
Response
OK
Response
identify the specific model of device.
<model Id>
OK
Execution
Command
AT+FMM
Parameter
<model Id> the ID of model
Reference
EIA/TIA-578-D
Note
3.2.39 AT+FMR FAX: Report Revision ID
AT+FMR FAX: Report Revision ID
Test Command
AT+FMR =?
Response
OK

Response
identify the version, revision level or data or other information of the
device.
Revision:<Revision Id>
OK
Execution
Command
AT+FMR
Parameter
<Revision Id> the version, revision level or data or other information
of the device.
Reference
EIA/TIA-578-D
Note
3.2.40 AT+VTD Tone Duration
AT+VTD Tone Duration
Response
+VTD: (list of supported <n>s)
OK
Test Command
AT+VTD=?
Parameter
See Write Command
Response
+VTD: <n>
OK
Read Command
AT+VTD?
Parameter
See Write Command
Response
This Command refers to an integer <n> that defines the length of tones
emitted as a result of the +VTS Command. This does not affect the D
Command.
OK
Write Command
AT+VTD = <n>
Parameter
<n> 1-255 duration of the tone in 1/10 seconds
Reference
GSM 07.07 [13]
Note
3.2.41 AT+VTS DTMF and Tone Generation
AT+VTS DTMF and Tone Generation
Test Command
AT+VTS=?
Response
+VTS: (list of supported <dtmf>s), ,(list of supported <duration>s)

OK
Parameters
See Write Command
Write Command
Generate tone
Duration is set by
+VTD
AT+VTS=<dtmf-
string>
Response
This Command allows the transmission of DTMF tones and arbitrary
tones in voice mode. These tones may be used (for example) when
announcing the start of a recording period.
Note: D is used only for dialing.
OK
+CME ERROR: <err>
Note: The Command is writing only.
Parameters
<dtmf-string> which has a max length of 20 characters, must be entered
between double quotes ("") and consists of combinations of the following
separated by commas. But a single character does not require quotes.
1) <dtmf> A single ASCII characters in the set 0-9, #,*, A-D. This is
interpreted as a sequence of DTMF tones whose duration is set by the
+VTD Command.
2) {<dtmf>, <duration>} This is interpreted as a DTMF tone whose
duration is determined by <duration>.
<duration> duration of the tone in 1/10 seconds range :1-255
Reference
GSM 07.07 [13]
Note
3.2.42 AT+CMUX Multiplexer Control
AT+CMUX Multiplexer Control
Response
+CMUX: list of supported (<mode>s),(<subset>s),(<port_spe
ed>s),(<N1>s),(<T1>s),(<N2>s),(<T2>s),(<T3>s),(<k>s)
OK
Test Command
AT+CMUX=?
Parameters
See Write Command
Read Command
AT+CMUX ?
Response:
+CMUX:[<mode>[,<subset>[,<port_speed>[,<N1>[,<T1>[,<N2>[,<T2
>[,<T3>[,<k>]]]]]]]]]

OK
ERROR
Parameters
See Write Command
Response
+CME ERROR: <err>
Write Command
AT+CMUX=<mo
de>[,<subset>[,<
port_speed>[,<N
1>[,<T1>[,<N2>[,
<T2>[,<T3>[,<k>
]]]]]]]]
Parameters
<mode> multiplexer transparency mechanism
0 Basic option
<subset> the way in which the multiplexer control channel is set up
0 UIH frames used only
<port_speed> transmission rate
1 9 600 bits/t
2 19 200 bits/t
3 38 400 bits/t
4 57 600 bits/t
5 115 200bit/s
6 230 400 bits/t
7 460 800 bits/t
proprietary values, available if MUX NEW PORT
SPEED FTR is activated
8 921 600 bits/t
Proprietary values, available if MUX NEW PORT
SPEED FTR is activated
<N1> maximum frame size
1-32768 Default: 127
<T1> acknowledgement timer in units of ten milliseconds
1-255 Default:10 (100 ms)
<N2> maximum number of re-transmissions
0-100 Default:3
<T2> response timer for the multiplexer control channel in units of
ten milliseconds
2-255 Default:30
<T3> wake up response timers in seconds
1-255 Default:10
<k> window size, for Advanced operation with Error Recovery
options
1-7 Default:2
Reference
GSM 07.07 [13]
Note
The multiplexing transmission rate is according to the current serial baud
rate. It is recommended to enable multiplexing protocol under 115200

bit/s baud rate
Multiplexer control channels are listed as follows:
Channel Number Type DLCI
None Multiplexer Control 0
1 07.07 and 07.05 1
2 07.07 and 07.05 2
3 07.07 and 07.05 3
4 07.07 and 07.05 4
3.2.43 AT+CNUM Subscriber Number
AT+CNUM Subscriber Number
Test Command
AT+CNUM=?
Response
OK
Response
+CNUM: [<alpha1>],<number1>,<type1>[,<speed>,<service>]
[<CR><LF>+CNUM:[<alpha2>],<number2>,<type2>[,<speed>,<serv
ice>]
[...]]
OK
+CME ERROR: <err>
Execution
Command
AT+CNUM
Parameters
<alphax> optional alphanumeric string associated with <numberx>;
used character set should be the one selected with
Command Select TE Character Set +CSCS
<numberx> string type (string should be included in quotation marks)
phone number of format specified by <typex>
<typex> type of address octet in integer format (refer GSM04.08[8]
subclause 10.5.4.7)
<speed> as defined by the +CBST Command
<service> (service related to the phone number: )
0 asynchronous modem
1 synchronous modem
2 PAD Access (asynchronous)
3 Packet Access (synchronous)
4 Voice
5 Fax
Reference
GSM 07.07 [13]
Note

3.2.44 AT+CPOL Preferred Operator List
AT+CPOL Preferred Operator List
Response
+CPOL: (list of supported <index>s),(list of supported <format>s)
OK
Test Command
AT+CPOL=?
Parameters
See Write Command
Response
+CPOL: <index1>,<format>,<oper1>
[<CR><LF>+CPOL: <index2>,<format>,<oper2>[…]]
OK
+CME ERROR: <err>
Read Command
AT+CPOL?
Parameters
See Write Command
Response
OK
+CME ERROR: <err>
Write Command
AT+CPOL=<ind
ex>[,<format>,<o
per>]
Parameters
<index> integer type: order number of operator in SIM preferred
operator list
<format> indicates whether alphanumeric or numeric
format used (see +COPS Command)
0 long format alphanumeric <oper>
1 short format alphanumeric <oper>
2 numeric <oper>
<oper> string type(string should be included in quotation marks)
Reference
GSM 07.07 [13]
Note
3.2.45 AT+COPN Read Operator Names
AT+COPN Read Operator Names
Test Command
AT+COPN=?
Response
OK
Execution
Command
AT+COPN
Response
+COPN: <numeric1>,<alpha1>
[<CR><LF>+COPN: <numeric2>,<alpha2>
[…]]

OK
+CME ERROR: <err>
Parameters
<numericn> string type (string should be included in quotation marks):
operator in numeric format (see +COPS)
<alphan> string type (string should be included in quotation marks):
operator in long alphanumeric format (see +COPS)
Reference
GSM 07.07 [13]
Note
3.2.46 AT+CFUN Set Phone Functionality
AT+CFUN Set Phone Functionality
Response
+CFUN: (list of supported <fun>s),(list of supported <rst>s)
OK
+CME ERROR: <err>
Test Command
AT+CFUN=?
Parameters
See Write Command
Response
+CFUN: <fun>
OK
+CME ERROR: <err>
Read Command
AT+CFUN?
Parameters
See Write Command
Response
OK
+CME ERROR: <err>
Write Command
AT+CFUN=<fun
>,[<rst>]
Parameters
<fun> 0 minimum functionality
1 full functionality (Default)
4 disable phone both transmit and receive RF circuits
<rst> 0 Do not reset the MT before setting it to <fun> power
level
1 Reset the MT before setting it to <fun> power level

Reference
GSM 07.07 [13]
Note
Minimum functionality mode(AT+CFUN=0)and RF disabled
functionality mode (AT+CFUN=4) cannot be switched to each other.
The <fun> power level will be written to flash except minimum
functionality.
AT+CFUN=1,1 can be used to reset module purposely. Response
string "OK" will be returned after module resets if baud rate is set to
fixed baud rate.
3.2.47 AT+CCLK Clock
AT+CCLK Clock
Test Command
AT+CCLK=?
Response
OK
Response
+CCLK: <time>
OK
+CME ERROR: <err>
Read Command
AT+CCLK?
Parameter
See Write Command
Response
OK
+CME ERROR: <err>
Write Command
AT+CCLK=<tim
e>
Parameter
<time> string type(string should be included in quotation marks)
value; format is "yy/MM/dd,hh:mm:ss±zz", where characters
indicate year (two last digits),month, day, hour, minutes,
seconds and time zone (indicates the difference, expressed in
quarters of an hour, between the local time and GMT; range
-47...+48). E.g. 6th of May 1994, 22:10:00 GMT+2 hours
equals to "94/05/06,22:10:00+08"
Reference
GSM 07.07 [13]
Note
3.2.48 AT+CSIM Generic SIM Access
AT+CSIM Generic SIM Access

Test Command
AT+CSIM=?
Response
OK
Response
+CSIM: <length>,<response>
OK
+CME ERROR: <err>
Write Command
AT+CSIM=<leng
th>,<Command>
Parameters
<length> integer type: length of characters sent to the TE in
<Command> or <response> (i.e. twice the number of
octets in the raw data)
<Command> string type(string should be included in quotation
marks): hex format: GSM 11.11 SIM Command sent
from the ME to the SIM
<response> string type(string should be included in quotation
marks): hex format: GSM 11.11 response from SIM to
<Command>
Reference
GSM 07.07 [13]
Note
3.2.49 AT+CALM Alert Sound Mode
AT+CALM Alert Sound Mode
Response
+CALM: (list of supported <mode>s)
OK
+CME ERROR: <err>
Test Command
AT+CALM=?
Parameter
See Write Command
Response
+CALM: <mode>
OK
+CME ERROR: <err>
Read Command
AT+CALM?
Parameter
See Write Command
Write Command Response

OK
+CME ERROR: <err>
AT+CALM=<mo
de>
Parameter
<mode> 0 normal mode
1 silent mode (all sounds from ME are prevented)
Reference
GSM 07.07 [13]
Note
If CALM is set to silent mode before, when user sets CALM to normal
mode during an incoming call, the module maintains silent this time. But
next time the normal mode works.
3.2.50 AT+CALS Alert Sound Select
AT+CALS Alert Sound Select
Response
+CALS: (list of supported <n>s)
OK
+CME ERROR: <err>
Test Command
AT+CALS=?
Parameter
See Write Command
Response
+CALS: <n>
OK
+CME ERROR: <err>
Read Command
AT+CALS?
Parameter
See Write Command
Response
OK
+CME ERROR: <err>
Write Command
AT+CALS=<n>
Parameter
<n> 0-19 alert sound type
Reference Note
3.2.51 AT+CRSL Ringer Sound Level
AT+CRSL Ringer Sound Level

+CRSL: (list of supported <level>s)
OK
+CME ERROR: <err>
AT+CRSL=?
Parameter
See Write Command
Response
+CRSL: <level>
OK
+CME ERROR: <err>
Read Command
AT+CRSL?
Parameter
See Write Command
Response
OK
+CME ERROR: <err>
Write Command
AT+CRSL=<leve
l>
Parameter
<level> integer type value (0-4) with manufacturer specific range
(smallest value represents the lowest sound level)
0 LEVEL OFF
1 LEVEL LOW
2 LEVEL MEDIUM
3 LEVEL HIGH
4 LEVEL CRESCENDO
Reference
GSM 07.07 [13]
Note
It is related to the command AT+CLVL.
3.2.52 AT+CLVL Loud Speaker Volume Level
AT+CLVL Loud Speaker Volume Level
Response
+CLVL: (list of supported <level>s)
OK
+CME ERROR: <err>
Test Command
AT+CLVL=?
Parameter
See Write Command

+CLVL: <level>
OK
+CME ERROR: <err>
AT+CLVL?
Parameter
See Write Command
Response
OK
+CME ERROR: <err>
Write Command
AT+CLVL=<leve
l>
Parameter
<level> 0-100 integer type value with manufacturer specific range
(smallest value represents the lowest sound level)
Reference
GSM 07.07 [13]
Note
3.2.53 AT+CMUT Mute Control
AT+CMUT Mute Control
Response
+CMUT: (list of supported <n>s)
OK
Test Command
AT+CMUT=?
Parameter
See Write Command
Response
+CMUT: <n>
OK
+CME ERROR: <err>
Read Command
AT+CMUT?
Parameter
See Write Command
Response
OK
+CME ERROR: <err>
Write Command
AT+CMUT=<n>
Parameter
<n> 0 mute off
1 mute on

Reference
GSM 07.07 [13]
Note
Only during a call this command can be set successfully.
3.2.54 AT+CPUC Price Per Unit and Currency Table
AT+CPUC Price Per Unit and Currency Table
Test Command
AT+CPUC=?
Response
OK
Response
+CPUC: <currency>,<ppu>
OK
+CME ERROR: <err>
Read Command
AT+CPUC?
Parameters
See Write Command
Response
OK
+CME ERROR: <err>
Write Command
AT+CPUC=<cur
rency>,<ppu>[,<
passwd>] Parameters
<currency> string type (string should be included in quotation marks);
three-character currency code (e.g. "GBP", "DEM");
character set as specified by Command Select TE
Character Set+CSCS
<ppu> string type (string should be included in quotation marks);
price per unit; dot is used as a decimal separator(e.g.
"2.66")
<passwd> string type (string should be included in quotation marks);
SIM PIN2
Reference
GSM 07.07 [13]
Note
3.2.55 AT+CCWE Call Meter Maximum Event
AT+CCWE Call Meter Maximum Event
Response
+CCWE: (list of supported <mode>s)
OK
+CME ERROR: <err>
Test Command
AT+CCWE=?
Parameter

See Write Command
Response
+CCWE: <mode>
OK
+CME ERROR: <err>
Read Command
AT+CCWE?
Parameter
See Write Command
Response
OK
+CME ERROR: <err>
Parameter
<mode> 0 Disable call meter warning event
1 Enable call meter warning event
Write Command
AT+CCWE=<m
ode>
Unsolicited result codes supported:
+CCWV Shortly before the ACM (Accumulated Call Meter)
maximum value is reached, an unsolicited result code
+CCWV will be sent, if enabled by this command. The
warning is issued approximately when 5 seconds call time
remains. It is also issued when starting a call if less than 5 s
call time remains.
Reference
GSM 07.07 [13]
Note
GSM 07.07 specifies 30 seconds, so SIMCom deviates from the
specification.
3.2.56 AT+CBC Battery Charge
AT+CBC Battery Charge
Response
+CBC: (list of supported <bcs>s),(list of supported <bcl>s),(<voltage>)
OK
Test Command
AT+CBC=?
Parameters
Execution
Command
AT+CBC
Response
+CBC: <bcs>, <bcl>,<voltage>

OK
+CME ERROR: <err>
Parameters
<bcs> charge status
0 ME is not charging
1 ME is charging
2 Charging has finished
<bcl> battery connection level
1...100 battery has 1-100 percent of capacity remaining
vent
<voltage> battery voltage(mV)
Reference
GSM 07.07 [13]
Note
This command depends on hardware and only be used when battery is
charging.
3.2.57 AT+CUSD Unstructured Supplementary Service Data
AT+CUSD Unstructured Supplementary Service Data
Response
+CUSD: (list of supported <n>s)
OK
Test Command
AT+CUSD=?
Parameter
See Write Command
Response
+CUSD: <n>
OK
Read Command
AT+CUSD?
Parameter
See Write Command
Response
OK
+CME ERROR: <err>
Write Command
AT+CUSD=<n>[,
<str>[,<dcs>]]
Parameters
<n> a numeric parameter which indicates control of the unstructured
supplementary service data
0 disable the result code presentation in the TE
1 enable the result code presentation in the TE

2 cancel session (not applicable to read Command response)
<str> string type(string should be included in quotation marks)
USSD-string
<dcs> Cell Broadcast Data Coding Scheme in integer format
(default 0)
Reference
GSM 03.38 [25]
Note
3.2.58 AT+CSSN Supplementary Services Notification
AT+CSSN Supplementary Services Notification
Response
+CSSN: (list of supported <n>s),(list of supported <m>s)
OK
Test Command
AT+CSSN=?
Parameters
See Write Command
Response
+CSSN: <n>,<m>
OK
Read Command
AT+CSSN?
Parameters
See Write Command
Response
OK
+CME ERROR: <err>
Write Command
AT+CSSN=<n>[,
<m>]
Parameters
<n> a numeric parameter which indicates whether to show the
+CSSI:<code1>[,<index>] result code presentation status
after a mobile originated call setup
0 disable
1 enable
<m> a numeric parameter which indicates whether to show the
+CSSU:<code2> result code presentation status during a
mobile terminated call setup or during a call, or when a
forward check supplementary service notification is received.
0 disable
1 enable
<code1> 0 unconditional call forwarding is active
1 some of the conditional call forwarding are active
2 call has been forwarded
3 call is waiting

4 this is a CUG call (also <index> present)
5 outgoing calls are barred
6 incoming calls are barred
7 CLIR suppression rejected
<index> closed user group index
<code2> 0 this is a forwarded call
1 this is a CUG call (also <index> present) (MT call
setup)
2 call has been put on hold (during a voice call)
3 call has been retrieved (during a voice call)
4 multiparty call entered (during a voice call)
5 call on hold has been released (this is not a SS
notification) (during a voice call)
6 forward check SS message received (can be received
whenever)
7 call is being connected (alerting) with the remote party
in alerting state in explicit call transfer operation (during
a voice call)
8 call has been connected with the other remote party in
explicit call transfer operation (also number and
subaddress parameters may be present) (during a voice
call or MT call setup)
9 this is a deflected call (MT call setup)
Reference Note

4 AT Commands According to GSM07.05
The GSM 07.05 commands are for performing SMS and CBS related operations. SIM900 supports
both Text and PDU modes.
4.1 Overview of AT Commands According to GSM07.05
Command Description
AT+CMGD DELETE SMS MESSAGE
AT+CMGF SELECT SMS MESSAGE FORMAT
AT+CMGL LIST SMS MESSAGES FROM PREFERRED STORE
AT+CMGR READ SMS MESSAGE
AT+CMGS SEND SMS MESSAGE
AT+CMGW WRITE SMS MESSAGE TO MEMORY
AT+CMSS SEND SMS MESSAGE FROM STORAGE
AT+CNMI NEW SMS MESSAGE INDICATIONS
AT+CPMS PREFERRED SMS MESSAGE STORAGE
AT+CRES RESTORE SMS SETTINGS
AT+CSAS SAVE SMS SETTINGS
AT+CSCA SMS SERVICE CENTER ADDRESS
AT+CSCB SELECT CELL BROADCAST SMS MESSAGES
AT+CSDH SHOW SMS TEXT MODE PARAMETERS
AT+CSMP SET SMS TEXT MODE PARAMETERS
AT+CSMS SELECT MESSAGE SERVICE
4.2 Detailed Descriptions of AT Commands According to GSM07.05
4.2.1 AT+CMGD Delete SMS Message
AT+CMGD Delete SMS Message
Response
+CMGD: (list of supported <index>s),(list of supported <delflag>s)
OK
Test Command
AT+CMGD=?
Parameters
See Write Command
Write Command
AT+CMGD=<in
dex>[,<delflag>]
Response
TA deletes message from preferred message storage <mem1> location
<index>.
OK
ERROR

+CMS ERROR:<err>
Parameters
<index> integer type; value in the range of location numbers supported
by the associated memory
<delflag> 0 Delete the message specified in <index>
1 Delete all read messages from preferred message storage,
leaving unread messages and stored mobile originated
messages (whether sent or not) untouched
2 Delete all read messages from preferred message storage
and sent mobile originated messages, leaving unread
messages and unsent mobile originated messages
untouched
3 Delete all read messages from preferred message storage,
sent and unsent mobile originated messages leaving unread
messages untouched
4 Delete all messages from preferred message storage
including unread messages
Reference
GSM 07.05
Note
4.2.2 AT+CMGF Select SMS Message Format
AT+CMGF Select SMS Message Format
Response
+CMGF: (list of supported <mode>s)
OK
Test Command
AT+CMGF=?
Parameter
See Write Command
Response
+CMGF: <mode>
OK
Read Command
AT+CMGF?
Parameter
See Write Command
Response
TA sets parameter to deNote which input and output format of messages to
use.
OK
Write Command
AT+CMGF=<mo
de>
Parameter
<mode> 0 PDU mode
1 text mode

Reference
GSM 07.05
Note
4.2.3 AT+CMGL List SMS Messages from Preferred Store
AT+CMGL List SMS Messages from Preferred Store
Response
+CMGL: (list of supported <stat>s)
OK
Test Command
AT+CMGL=?
Parameter
See Write Command
Parameters
1) If text mode:
<stat> "REC UNREAD" Received unread messages
"REC READ" Received read messages
"STO UNSENT" Stored unsent messages
"STO SENT" Stored sent messages
"ALL" All messages
<mode> 0 normal
1 not change status of the specified SMS record
2) If PDU mode:
<stat> 0 Received unread messages
1 Received read messages
2 Stored unsent messages
3 Stored sent messages
4 All messages
<mode> 0 normal
Write Command
AT+CMGL=<sta
t>[,<mode>]
Response
TA returns messages with status value <stat> from message storage
<mem1> to the TE. If status of the message is 'received unread', status in the
storage changes to 'received read'.
1) If text mode (+CMGF=1) and Command successful:
for SMS-SUBMITs and/or SMS-DELIVERs:
+CMGL:
<index>,<stat>,<oa/da>,[<alpha>],[<scts>][,<tooa/toda>,<length>]<CR
><LF><data>[<CR><LF>
+CMGL:
<index>,<stat>,<da/oa>,[<alpha>],[<scts>][,<tooa/toda>,<length>]<CR
><LF><data>[...]]
for SMS-STATUS-REPORTs:
+CMGL:

<index>,<stat>,<fo>,<mr>,[<ra>],[<tora>],<scts>,<dt>,<st>[<CR><LF
>
+CMGL:
<index>,<stat>,<fo>,<mr>,[<ra>],[<tora>],<scts>,<dt>,<st>[...]]
for SMS-COMMANDs:
+CMGL: <index>,<stat>,<fo>,<ct>[<CR><LF>
+CMGL: <index>,<stat>,<fo>,<ct>[...]]
for CBM storage:
+CMGL:<index>,<stat>,<sn>,<mid>,<page>,<pages><CR><LF><data
><CR><LF>
+CMGL:
<index>,<stat>,<sn>,<mid>,<page>,<pages><CR><LF><data>[...]]
OK
2) If PDU mode (+CMGF=0) and Command successful:
+CMGL:<index>,<stat>,[<alpha>],<length><CR><LF><pdu><CR><L
F>
+CMGL: <index>,<stat>,[alpha],<length><CR><LF><pdu>[...]]
OK
3)If error is related to ME functionality:
+CMS ERROR: <err>
Parameters
<alpha> string type(string should be included in quotation marks)
alphanumeric representation of <da> or <oa> corresponding to
the entry found in MT phonebook; implementation of this
feature is manufacturer specific; used character set should be
the one selected with Command Select TE Character Set
+CSCS (see definition of this Command in TS 07.07)
<da> GSM 03.40 TP-Destination-Address Address-Value field in
string format; BCD numbers (or GSM default alphabet
characters) are converted to characters of the currently selected
TE character set (refer Command+CSCS in TS 07.07); type of
address given by <toda>
<data> In the case of SMS: GSM 03.40 TP-User-Data in text mode
responses; format:
- if <dcs> indicates that GSM 03.38 default alphabet is used and
<fo> indicates that GSM 03.40
TPUser-Data-Header-Indication is not set:
- if TE character set other than "HEX" (refer Command Select
TE Character Set +CSCS in TS 07.07):ME/TA
converts GSM alphabet into current TE character set

according to rules of Annex A
- if TE character set is "HEX": ME/TA converts each 7-bit
character of GSM alphabet into two IRA character
long hexadecimal number (e.g. character P (GSM 23)
is presented as 17 (IRA 49 and 55))
- if <dcs> indicates that 8-bit or UCS2 data coding scheme is
used, or <fo> indicates that GSM 03.40
TP-User-Data-Header-Indication is set: ME/TA
converts each 8-bit octet into two IRA character long
hexadecimal number (e.g. octet with integer value 42
is presented to TE as two characters 2A (IRA 50 and
65)) In the case of CBS: GSM 03.41 CBM Content of
Message in text mode responses; format:
- if <dcs> indicates that GSM 03.38 default alphabet is used:
- if TE character set other than "HEX" (refer Command +CSCS
in GSM 07.07): ME/TA converts GSM alphabet into
current TE character set according to rules of Annex A
long hexadecimal number
used: ME/TA converts each 8-bit octet into two IRA
character long hexadecimal number
<length> integer type value indicating in the text mode (+CMGF=1)
the length of the message body <data> (or <cdata>) in
characters; or in PDU mode (+CMGF=0), the length of the
actual TP data unit in octets (i.e. the RP layer SMSC address
octets are not counted in the length)
<oa> GSM 03.40 TP-Originating-Address Address-Value field in
characters) are converted to characters of the currently
selected TE character set (refer Command +CSCS in TS
07.07); type of address given by <tooa>
<pdu> In the case of SMS: GSM 04.11 SC address followed by
GSM 03.40 TPDU in hexadecimal format: ME/TA converts
each octet of TP data unit into two IRA character long
hexadecimal number (e.g. octet with integer value 42 is
presented to TE as two characters 2A (IRA 50 and 65)). In
the case of CBS: GSM 03.41 TPDU in hexadecimal format.
<scts> GSM 03.40 TP-Service-Center-Time-Stamp in time-string
format (refer <dt>)
<toda> GSM 04.11 TP-Destination-Address Type-of-Address octet

in integer format (when first character of <da> is + (IRA 43)
default is 145, otherwise default is 129)
<tooa> GSM 04.11 TP-Originating-Address Type-of-Address octet in
integer format (default refer<toda>)
1) If text mode:
the same as AT+CMGL="REC UNREAD", received unread messages
2) If PDU mode:
the same as AT+CMGL=0, received unread messages
See more messages please refer to Write Command.
Execution
Command
AT+CMGL
Parameters
See Write Command
Reference
GSM 07.05
Note
4.2.4 AT+CMGR Read SMS Message
AT+CMGR Read SMS Message
Test Command
AT+CMGR=?
Response
OK
Parameters
<mode> 0 normal
Write Command
AT+CMGR=<in
dex>[,<mode>]
Response
TA returns SMS message with location value <index> from message storage
<mem1> to the TE. If status of the message is 'received unread', status in the
storage changes to 'received read'.
1) If text mode (+CMGF=1) and Command successful:
for SMS-DELIVER:
+CMGR:
<stat>,<oa>,[<alpha>],<scts>[,<tooa>,<fo>,<pid>,<dcs>,<sca>,<tosca>,
<length>]<CR><LF><data>
for SMS-SUBMIT:
+CMGR:
<stat>,<da>,[<alpha>][,<toda>,<fo>,<pid>,<dcs>,[<vp>],<sca>,<tosca>,
<length>]<CR><LF><data>
for SMS-STATUS-REPORTs:
+CMGR: <stat>,<fo>,<mr>,[<ra>],[<tora>],<scts>,<dt>,<st>
for SMS-COMMANDs:
+CMGR:

<stat>,<fo>,<ct>[,<pid>,[<mn>],[<da>],[<toda>],<length><CR><LF><
cdata>]
for CBM storage:
+CMGR: <stat>,<sn>,<mid>,<dcs>,<page>,<pages><CR><LF><data>
2) If PDU mode (+CMGF=0) and Command successful:
+CMGR: <stat>,[<alpha>],<length><CR><LF><pdu>
OK
3) If error is related to ME functionality:
+CMS ERROR: <err>
Parameters
<alpha> string type (string should be included in quotation marks)
alphanumeric representation of <da> or <oa> corresponding
to the entry found in MT phonebook; implementation of this
feature is manufacturer specific
selected TE character set (specified by +CSCS in TS 07.07);
type of address given by <toda>
<data> In the case of SMS: GSM 03.40 TP-User-Data in text mode
responses; format:
- if <dcs> indicates that GSM 03.38 default alphabet is used and
<fo> indicates that GSM 03.40
TPUser-Data-Header-Indication is not set:
- if TE character set other than "HEX" (refer Command Select
TE Character Set +CSCS in TS 07.07):ME/TA
converts GSM alphabet into current TE character set
according to rules of Annex A
long hexadecimal number (e.g. character P (GSM 23)
is presented as 17 (IRA 49 and 55))
used, or <fo> indicates that GSM 03.40
TP-User-Data-Header-Indication is set: ME/TA
converts each 8-bit octet into two IRA character long
hexadecimal number (e.g. octet with integer value 42
is presented to TE as two characters 2A (IRA 50 and
65)) In the case of CBS: GSM 03.41 CBM Content of
Message in text mode responses; format:
- if <dcs> indicates that GSM 03.38 default alphabet is used:

- if TE character set other than "HEX" (refer Command +CSCS
in GSM 07.07): ME/TA converts GSM alphabet into
current TE character set according to rules of Annex A
long hexadecimal number
used: ME/TA converts each 8-bit octet into two IRA
character long hexadecimal number
<dcs> depending on the Command or result code: GSM 03.38 SMS
Data Coding Scheme (default 0), or Cell Broadcast Data
Coding Scheme in integer format
<fo> depending on the Command or result code: first octet of GSM
03.40 SMS-DELIVER, SMS-SUBMIT (default 17),
SMS-STATUS-REPORT, or SMS-COMMAND (default 2)
in integer format
<length> integer type value indicating in the text mode (+CMGF=1)
the length of the message body <data> (or <cdata>) in
characters; or in PDU mode (+CMGF=0), the length of the
actual TP data unit in octets (i.e. the RP layer SMSC address
octets are not counted in the length)
<mid> GSM 03.41 CBM Message Identifier in integer format
characters) are converted characters of the currently selected
TE character set (specified by +CSCS in TS 07.07); type of
address given by <tooa>
<pid> GSM 03.40 TP-Protocol-Identifier in integer format
(default 0)
<sca> GSM 04.11 RP SC address Address-Value field in string
format; BCD numbers (or GSM default alphabet characters)
are converted to characters of the currently selected TE
character set (specified by +CSCS in TS 07.07); type of
address given by <tosca>
<scts> GSM 03.40 TP-Service-Centre-Time-Stamp in time-string
format (refer <dt>)
<stat> 0 "REC UNREAD" Received unread messages
1 "REC READ" Received read messages

2 "STO UNSENT" Stored unsent messages
3 "STO SENT" Stored sent messages
<tooa> GSM 04.11 TP-Originating-Address Type-of-Address octet
in integer format (default refer<toda>)
<tosca> GSM 04.11 RP SC address Type-of-Address octet in integer
format (default refer <toda>)
<vp> depending on SMS-SUBMIT <fo> setting: GSM 03.40
TP-Validity-Period either in integer format (default 167) or in
time-string format (refer <dt>)
Reference
GSM 07.05
Note
4.2.5 AT+CMGS Send SMS Message
AT+CMGS Send SMS Message
Test Command
AT+CMGS=?
Response
OK
Parameters
string format(string should be included in quotation marks);
BCD numbers (or GSM default alphabet characters) are
converted to characters of the currently selected TE character
set (specified by +CSCS in TS 07.07); type of address given
by <toda>
<length> integer type value (not exceed 160 bytes) indicating in the
text mode (+CMGF=1) the length of the message body
<data> (or <cdata>) in characters; or in PDU mode
(+CMGF=0), the length of the actual TP data unit in octets
(i.e. the RP layer SMSC address octets are not counted in the
length)
Write Command
1) If text mode
(+CMGF=1):
+CMGS=<da>[,
<toda>]<CR>
text is entered
<ctrl-Z/ESC>
ESC quits without
sending
2) If PDU mode
(+CMGF=0):
+CMGS=<length
><CR>
PDU is given
<ctrl-Z/ESC>
Response
TA sends message from a TE to the network (SMS-SUBMIT). Message
reference value <mr> is returned to the TE on successful message delivery.
Optionally (when +CSMS <service> value is 1 and network supports)
<scts> is returned. Values can be used to identify message upon unsolicited
delivery status report result code.
1) If text mode(+CMGF=1) and sending successful:
+CMGS: <mr>

OK
2) If PDU mode(+CMGF=0) and sending successful:
+CMGS: <mr>
OK
+CMS ERROR: <err>
Parameter
<mr> GSM 03.40 TP-Message-Reference in integer format
Reference
GSM 07.05
Note
If TE Character Set is GSM, it supports 160-byte maximum; If TE
Character Set is UCS2, it supports 70-word maximum.
4.2.6 AT+CMGW Write SMS Message to Memory
AT+CMGW Write SMS Message to Memory
Test Command
AT+CMGW=?
Response
OK
Response
TA transmits SMS message (either SMS-DELIVER or SMS-SUBMIT)
from TE to memory storage <mem2>. Memory location <index> of the
stored message is returned. By default message status will be set to 'stored
unsent', but parameter <stat> allows also other status values to be given.
If writing is successful:
+CMGW: <index>
OK
+CMS ERROR: <err>
Write Command
1) If text mode
(+CMGF=1):
AT+CMGW=<o
a/da>[,<tooa/tod
a>]
<CR> text is
entered
<ctrl-Z/ESC>
<ESC> quits
without sending
2) If PDU mode
(+CMGF=0):
AT+CMGW=<le
ngth><CR>
PDU is given
<ctrl-Z/ESC>
Parameters
set (specified by +CSCS in TS 07.07);type of address given
by <tooa>

by <toda>
<tooa> GSM 04.11 TP-Originating-Address Type-of-Address octet
in integer format (default refer <toda>)
<length> integer type value (not exceed 160 bytes) indicating in the
text mode (+CMGF=1) the length of the message body
<data> (or <cdata>) in characters; or in PDU mode
(+CMGF=0), the length of the actual TP data unit in octets
(i.e. the RP layer SMSC address octets are not counted in the
length)
<index> Index of message in selected storage <mem2>
Execution
Command
AT+CMGW
Response
TA transmits SMS message (either SMS-DELIVER or SMS-SUBMIT)
from TE to memory storage <mem2>. Memory location <index> of the
stored message is returned. By default message status will be set to 'stored
unsent', but parameter <stat> allows also other status values to be given.
If writing is successful:
+CMGW: <index>
OK
+CMS ERROR: <err>
Reference
GSM 07.05
Note

4.2.7 AT+CMSS Send SMS Message from Storage
AT+CMSS Send SMS Message from Storage
Test Command
AT+CMSS=?
Response
OK
Response
TA sends message with location value <index> from message storage
<mem2> to the network (SMS-SUBMIT). If new recipient address <da> is
given, it shall be used instead of the one stored with the message. Reference
value <mr> is returned to the TE on successful message delivery. Values can
be used to identify message upon unsolicited delivery status report result
code.
1) If text mode(+CMGF=1) and sending successful:
+CMSS: <mr>
OK
2) If PDU mode(+CMGF=0) and sending successful:
+CMSS: <mr>
OK
+CMS ERROR: <err>
Write Command
AT+CMSS=<ind
ex>,<da>[,<toda
>]
Parameters
by <toda>
<mr> GSM 03.40 TP-Message-Reference in integer format
Reference
GSM 07.05
Note
4.2.8 AT+CNMI New SMS Message Indications
AT+CNMI New SMS Message Indications
Test Command
AT+CNMI=?
Response
+CNMI: (list of supported <mode>s),(list of supported <mt>s),(list of

supported <bm>s),(list of supported <ds>s),(list of supported <bfr>s)
OK
Parameters
See Write Command
Response
+CNMI: <mode>,<mt>,<bm>,<ds>,<bfr>
OK
Read Command
AT+CNMI?
Parameters
See Write Command
Response
TA selects the procedure for how the receiving of new messages from the
network is indicated to the TE when TE is active, e.g. DTR signal is ON. If
TE is inactive (e.g. DTR signal is OFF), message receiving should be done
as specified in GSM 03.38.
OK
ERROR
Write Command
AT+CNMI=<mo
de>[,<mt>[,<bm
>[,<ds>[,<bfr>]]]
]
Parameters
<mode> 0 Buffer unsolicited result codes in the TA. If TA result
code buffer is full, indications can be buffered in some
other place or the oldest indications may be discarded
and replaced with the new received indications.
1 Discard indication and reject new received message
unsolicited result codes when TA-TE link is reserved
(e.g. in on-line data mode). Otherwise forward them
directly to the TE.
2 Buffer unsolicited result codes in the TA when TA-TE
link is reserved (e.g. in on-line data mode) and flush
them to the TE after reservation. Otherwise forward
them directly to the TE.
3 Forward unsolicited result codes directly to the TE.
TA-TE link specific inband technique used to embed
result codes and data when TA is in on-line data mode.
<mt> (the rules for storing received SMs depend on its data coding
scheme (refer GSM 03.38 [2]), preferred memory
storage (+CPMS) setting and this value):
0 No SMS-DELIVER indications are routed to the TE.
1 If SMS-DELIVER is stored into ME/TA, indication of
the memory location is routed to the TE using
unsolicited result code: +CMTI: <mem>,<index>
2 SMS-DELIVERs (except class 2) are routed directly to

the TE using unsolicited result code: +CMT:
[<alpha>],<length><CR><LF><pdu> (PDU mode
enabled) or +CMT: <oa>, [<alpha>],<scts>
[,<tooa>,<fo>,<pid>,<dcs>,<sca>,<tosca>,<length
>]<CR><LF><data> (text mode enabled; about
parameters in italics, refer Command Show Text Mode
Parameters +CSDH). Class 2 messages result in
indication as defined in <mt>=1.
3 Class 3 SMS-DELIVERs are routed directly to TE
using unsolicited result codes defined in <mt>=2.
Messages of other classes result in indication as
defined in <mt>=1.
<bm> (the rules for storing received CBMs depend on its data
coding scheme (refer GSM 03.38 [2]), the setting of
Select CBM Types (+CSCB) and this value):
0 No CBM indications are routed to the TE.
2 New CBMs are routed directly to the TE using
unsolicited result code: +CBM:
<length><CR><LF><pdu> (PDU mode enabled) or
+CBM:
<sn>,<mid>,<dcs>,<page>,<pages><CR><LF><data>
(text mode enabled).
<ds> 0 No SMS-STATUS-REPORTs are routed to the TE.
1 SMS-STATUS-REPORTs are routed to the TE using
unsolicited result code: +CDS:
<length><CR><LF><pdu> (PDU mode enabled) or
+CDS: <fo>,<mr>,[<ra>],[<tora>],<scts>,<dt>,<st>
(text mode enabled)
<bfr> 0 TA buffer of unsolicited result codes defined within
this Command is flushed to the TE when <mode> 1...3
is entered (OK response shall be given before flushing
the codes).
1 TA buffer of unsolicited result codes defined within
this command is cleared when <mode> 1…3 is entered
1.Indication that new message has been received
+CMTI: <mem>,<index>
2.Short message is output directly
+CMT: [<alpha>],<length><CR><LF><pdu>
3.Cell broadcast message is output directly
+CBM: <length><CR><LF><pdu>
Reference
GSM 07.05
Note

4.2.9 AT+CPMS Preferred SMS Message Storage
AT+CPMS Preferred SMS Message Storage
Response
+CPMS: (list of supported <mem1>s),(list of supported <mem2>s),(list of
supported <mem3>s)
OK
Test Command
AT+CPMS=?
Parameters
See Write Command
Response
+CPMS: <mem1>,<used1>,<total1>,<mem2>,<used2>,<total2>,
<mem3>,<used3>,<total3>
OK
ERROR
Read Command
AT+CPMS?
Parameters
See Write Command
Response
TA selects memory storages <mem1>, <mem2> and <mem3> to be used for
reading, writing, etc.
+CPMS: <used1>,<total1>,<used2>,<total2>,<used3>,<total3>
OK
ERROR
Write Command
AT+CPMS=
<mem1>
[,<mem2>
[,<mem3>]]
Parameters
<mem1> Messages to be read and deleted from this memory storage
"SM" SIM message storage
<mem2> Messages will be written and sent to this memory storage
<mem3> Received messages will be placed in this memory storage if
routing to PC is not set ("+CNMI")
<usedx> integer type; Number of messages currently in <memx>
<totalx> integer type; Number of messages storable in <memx>
Reference
GSM 07.05
Note
4.2.10 AT+CRES Restore SMS Settings
AT+CRES Restore SMS Settings

Response
+CRES: (list of supported <profile>s)
OK
Test Command
AT+CRES=?
Parameter
See Write Command
Response
TA restores SMS settings for +CSCA, +CSMP from non-volatile memory
to active memory.
OK
ERROR
Write Command
AT+CRES=<pro
file>
Parameter
<profile> 0 Restore SM service settings from profile 0
1 Restore SM service settings from profile 1
Execution
Command
AT+CRES
Response
Same as AT+CRES=0.
OK
+CMS ERROR <err>
Reference
GSM 07.05
Note
4.2.11 AT+CSAS Save SMS Settings
AT+CSAS Save SMS Settings
Response
+CSAS: (list of supported <profile>s)
OK
Test Command
AT+CSAS=?
Parameter
See Write Command
Response
TA saves SMS settings for +CSCA, +CSMP from non-volatile memory to
active memory.
OK
ERROR
Write Command
AT+CSAS=<prof
ile>
Parameter
<profile> 0 Save SM service setting in profile 0
1 Save SM service setting in profile 1
Execution
Command
AT+CSAS
Response
Same as AT+CSAS=0
OK

+CMS ERROR <err>
Reference
GSM 07.05
Note
4.2.12 AT+CSCA SMS Service Center Address
AT+CSCA SMS Service Center Address
Test Command
AT+CSCA=?
Response
OK
Response
+CSCA: <sca>,<tosca>[,<scaAlpha>]
OK
Read Command
AT+CSCA?
Parameters
See Write Command
Response
TA updates the SMSC address, through which mobile originated SMS are
transmitted. In text mode, setting is used by send and writes commands. In
PDU mode, setting is used by the same commands, but only when the
length of the SMSC address coded into <pdu> parameter equals zero.
Note: The Command writes the parameters in NON-VOLATILE memory.
OK
+CME ERROR: <err>
Write Command
AT+CSCA=
<sca>[,<tosca>]
Parameters
<sca> GSM 04.11 RP SC address Address-Value field in
string format(string should be included in quotation
marks); BCD numbers (or GSM default alphabet
selected TE character set (specified by +CSCS in TS
07.07); type of address given by <tosca>
<tosca> Service center address format GSM 04.11 RP SC
address Type-of-Address octet in integer format
(default refer <toda>)
<scaAlpha> string type(string should be included in quotation
marks)
Service center address alpha data
Reference
GSM 07.05
Note

4.2.13 AT+CSCB Select Cell Broadcast SMS Messages
AT+CSCB Select Cell Broadcast SMS Messages
Response
+CSCB: (list of supported <mode>s)
OK
Test Command
AT+CSCB=?
Parameter
See Write Command
Response
+CSCB: <mode>,<mids>,<dcss>
OK
Read Command
AT+CSCB?
Parameters
See Write Command
Response
TA selects which types of CBMs are to be received by the ME.
OK
+CMS ERROR: <err>
Write Command
AT+CSCB=
<mode>[,mids>[,
<dcss>]]
Parameters
<mode> 0 message types specified in <mids> and <dcss> are
accepted
1 message types specified in <mids> and <dcss> are not
accepted.
<mids> string type (string should be included in quotation marks); all
different possible combinations of CBM message identifiers
(refer <mid>) (default is empty string); e.g. "0,1,5,320,922".
Total 15 different <mids> values can be supported. <mids>
values cannot be written consecutively, such as "100-200"
<dcss> string type(string should be included in quotation marks); all
different possible combinations of CBM data coding schemes
(refer <dcs>) (default is empty string); e.g. "0,5". Total 5
different <dcss> values can be supported. <dcss> values
cannot be written consecutively, such as "0-5"
Reference
GSM 07.05
Note
AT+CSCB=0 will reset <mids> and <dcss> and select no <mids> and
no <dcss>.
AT+CSCB=1 means all <dcss> are accepted but this command has no
effect on the list of the <mids> accepted. "0-255" means all <dcss> are

accepted.
AT+CSCB=0, <mids> will add the <mids> values in the <mids>
current list handled by module.
AT+CSCB=0, <dcss> will add the <dcss> values in the <dcss> current
list handled by module.
If AT+CSCB=0, <mids> is received while the list of <mids> is full,
OK is returned and new value is not added.
4.2.14 AT+CSDH Show SMS Text Mode Parameters
AT+CSDH Show SMS Text Mode Parameters
Response
+CSDH: (list of supported <show>s)
OK
Test Command
AT+CSDH=?
Parameter
See Write Command
Response
+CSDH: <show>
OK
Read Command
AT+CSDH?
Parameter
See Write Command
Response
TA determines whether detailed header information is shown in text mode
result codes.
OK
Write Command
AT+CSDH=<sho
w>
Parameter
<show> 0 do not show header values defined in commands +CSCA
and +CSMP (<sca>, <tosca>, <fo>, <vp>, <pid> and
<dcs>) nor <length>, <toda> or <tooa> in +CMT,
+CMGL, +CMGR result codes for SMS-DELIVERs and
SMS-SUBMITs in text mode
1 show the values in result codes
Reference
GSM 07.05
Note
4.2.15 AT+CSMP Set SMS Text Mode Parameters
AT+CSMP Set SMS Text Mode Parameters

+CSMP: (list of supported <fo>s),(list of supported <vp>s),(list of
supported <pid>s),(list of supported <dcs>s)
OK
AT+CSMP=?
Parameters
See Write Command
Response
+CSMP: <fo>,<vp>,<pid>,<dcs>
OK
Read Command
AT+CSMP?
Parameters
See Write Command
Response
TA selects values for additional parameters needed when SM is sent to the
network or placed in a storage when text mode is selected (+CMGF=1). It is
possible to set the validity period starting from when the SM is received by
the SMSC (<vp> is in range 0... 255) or define the absolute time of the
validity period termination (<vp> is a string).
OK
Write Command
AT+CSMP=[<fo
>[,<vp>,<pid>,<
dcs>]]
Parameters
<fo> depending on the Command or result code: first octet of GSM
03.40 SMS-DELIVER, SMS-SUBMIT (default 17),
SMS-STATUS-REPORT, or SMS-COMMAND (default 2) in
integer format. SMS status report is supported under text mode if
<fo> is set to 49.
<vp> depending on SMS-SUBMIT <fo> setting: GSM 03.40
TP-Validity-Period either in integer format (default 167) or in
time-string format (refer <dt>)
<pid> GSM 03.40 TP-Protocol-Identifier in integer format (default 0).
<dcs> GSM 03.38 SMS Data Coding Scheme in Integer format.
Reference
GSM 07.05
Note
4.2.16 AT+CSMS Select Message Service
AT+CSMS Select Message Service
Test Command
AT+CSMS=?
Response
+CSMS: (list of supported <service>s)
OK

Parameter
See Write Command
Response
+CSMS: <service>,<mt>,<mo>,<bm>
OK
Read Command
AT+CSMS?
Parameters
See Write Command
Response
+CSMS: <mt>,<mo>,<bm>
OK
+CME ERROR: <err>
Write Command
AT+CSMS=
<service>
Parameters
<service> 0 GSM 03.40 and 03.41 (the syntax of SMS AT commands
is compatible with GSM 07.05 Phase 2 version 4.7.0;
Phase 2+ features which do not require new Command
syntax may be supported (e.g. correct routing of
messages with new Phase 2+ data coding schemes))
1 GSM 03.40 and 03.41 (the syntax of SMS AT
commands is compatible with GSM 07.05 Phase 2+
version; the requirement of <service> setting 1 is
mentioned under corresponding command descriptions)
<mt> Mobile Terminated Messages:
0 Type not supported
1 Type supported
<mo> Mobile Originated Messages:
1 Type supported
<bm> Broadcast Type Messages:
1 Type supported
Reference
GSM 07.05
Note

5 AT Commands for SIM Application Toolkit
5.1 STK AT Command
*PSSTK command is defined to support SIM toolkit by AT commands. Only part of SIM toolkit
commands that interact with user or MMI can be controlled. All other SIM toolkit mechanism
such as terminal profile, SMS or CBM data download, call control or MO SMS control by SIM,
event download and all command that does not require interaction with the user (or screen) are
internally managed by the ME.
AT*PSSTKI SIM Toolkit interface configuration
Response
*PSSTKI: (list of supported <mode>s)
OK
Test Command
AT*PSSTKI=?
Parameter
See Write Command
Response
*PSSTKI: <mode>
OK
ERROR
Read Command
AT*PSSTKI?
Parameter
See Write Command
Response
OK
ERROR
Write Command
AT*PSSTKI
=<mode>
Parameter
<mode> integer type
0 SIM toolkit notification is disabled
1 SIM toolkit notification is enabled
Reference Note
If AT*PSSTKI=1 is set, *PSSTK: "SETUP MENU" string will be sent out
after power on.
AT*PSSTK SIM toolkit control
Test Command
AT*PSSTK=?
Response
*PSSTK: (list of supported <response type>s)
Parameter
SIM300_ATC_V1.03 1 08.29.2008

See Write Command
Read Command
AT*PSSTK?
Response
ERROR
Response
OK
ERROR
Write Command
AT*PSSTK
=<response
type>,[<paramet
er1>,…,<parame
tern]
Parameters
<response type> string type that represents the type of response to be sent
to SIM
"COMMAND REJECTED"
"NOTIFICATION"
"SETUP CALL"
"DISPLAY TEXT"
"GET INKEY"
"GET INPUT"
"PLAY TONE"
"SELECT ITEM"
"SETUP MENU"
"REMOVE MENU"
"MENU SELECTION"
"ALL CALLS DISCONNECTED"
"USER ACTIVITY"
"IDLE SCREEN AVAILABLE"
"SETUP CALL TERMINATED"
"GET ITEM LIST"
"LANGUAGE NOTIFICATION"
"SETUP IDLE MODE TEXT"
<parameteri> integer or string type which number of parameters
depends on response type.
Reference Note

6 AT Commands Special for SIMCOM
6.1 Overview
Command Description
AT+SIDET CHANGE THE SIDE TONE GAIN LEVEL
AT+CPOWD POWER OFF
AT+SPIC TIMES REMAINED TO INPUT SIM PIN/PUK
AT+CMIC CHANGE THE MICROPHONE GAIN LEVEL
AT+CALA SET ALARM TIME
AT+CALD DELETE ALARM
AT+CADC READ ADC
AT+CSNS SINGLE NUMBERING SCHEME
AT+CDSCB RESET CELL BROADCAST
AT+CMOD CONFIGURE ALTERNATING MODE CALLS
AT+CFGRI INDICATE RI WHEN USING URC
AT+CLTS GET LOCAL TIMESTAMP
AT+CEXTHS EXTERNAL HEADSET JACK CONTROL
AT+CEXTBUT HEADSET BUTTON STATUS REPORTING
AT+CSMINS SIM INSERTED STATUS REPORTING
AT+CLDTMF LOCAL DTMF TONE GENERATION
AT+CDRIND CS VOICE/DATA CALL TERMINATION INDICATION
AT+CSPN GET SERVICE PROVIDER NAME FROM SIM
AT+CCVM GET AND SET THE VOICE MAIL NUMBER ON THE SIM
AT+CBAND GET AND SET MOBILE OPERATION BAND
AT+CHF CONFIGURE HANDS FREE OPERATION
AT+CHFA SWAP THE AUDIO CHANNELS
AT+CSCLK CONFIGURE SLOW CLOCK
AT+CENG SWITCH ON OR OFF ENGINEERING MODE
AT+SCLASS0 STORE CLASS 0 SMS TO SIM WHEN RECEIVED CLASS 0 SMS
AT+CCID SHOW ICCID
AT+CMTE SET CRITICAL TEMPERATURE OPERATING MODE OR QUERY
TEMPERATURE
AT+CBTE BATTERY TEMPERATURE QUERY
AT+CSDT SWITCH ON OR OFF DETECTING SIM CARD
AT+CMGDA DELETE ALL SMS
AT+STTONE PLAY SIM TOOLKIT TONE
AT+SIMTONE GENERATE SPECIFIC TONE

AT+CCPD ENABLE OR DISABLE ALPHA STRING
AT+CGID GET SIM CARD GROUP IDENTIFIER
AT+MORING SHOW STATE OF MOBILE ORIGINATED CALL
AT+CMGHEX ENABLE OR DISABLE SENDING NON-ASCII CHARACTER SMS
AT+AUTEST AUDIO CHANNEL LOOPBACK TEST
AT+CCODE CONFIGURE SMS CODE MODE
AT+CIURC ENABLE OR DISABLE INITIAL URC PRESENTATION
AT+CPSPWD CHANGE PS SUPER PASSWORD
AT+EXUNSOL ENABLE OR DISABLE PROPRIETARY UNSOLICITED
INDICATIONS
AT+CGMSCLASS CHANGE GPRS MULTISLOT CLASS
AT+CDEVICE VIEW CURRENT FLASH DEVICE TYPE
AT+CCALR CALL READY QUERY
AT+GSV DISPLAY PRODUCT IDENTIFICATION INFORMATION
AT+SGPIO CONTROL THE GPIO
AT+SPWM GENERATE THE PULSE-WIDTH-MODULATION
AT+ECHO ECHO CANCELLATION CONTROL
AT+CAAS CONTROL AUTO AUDIO SWITCH
AT+SVR CONFIGURE VOICE CODING TYPE FOR VOICE CALLS
AT+GSMBUSY REJECT INCOMING CALL
6.2 Detailed Descriptions of Commands
6.2.1 AT+SIDET Change the Side Tone Gain Level
AT+SIDET Change the Side Tone Gain Level
Response
+SIDET: (list of supported <channel>s),(list of supported <gainlevel>s)
OK
Test Command
AT+SIDET=?
Parameters
See Write Command
Response:
+SIDET: <gainlevel>,<gainlevel>
OK
Read Command
AT+SIDET?
Parameters
See Write Command

Response
OK
ERROR
Write Command
AT+SIDET=<ch
annel>,<gainleve
l> Parameters
<channel> 0 main audio handset channel
1 aux audio headset channel
2 main audio handfree channel
3 aux audio handfree channel
<gainlevel> int: 0 – 16
Reference Note
<gainlevel> value is related to channel specific.
6.2.2 AT+CPOWD Power Off
AT+CPOWD Power Off
Response
[NORMAL POWER DOWN]
Write Command
AT+CPOWD=
<n> Parameter
<n> 0 Power off urgently ( Will not send out NORMAL POWER
DOWN)
1 Normal power off (Will send out NORMAL POWER
DOWN)
Reference Note
6.2.3 AT+SPIC Times Remained to Input SIM PIN/PUK
AT+SPIC Times Remained to Input SIM PIN/PUK
Response
Times remained to input SIM PIN
+SPIC: <pin1>,<pin2>,<puk1>,<puk2>
OK
Execution
Command
AT+SPIC
Parameters
<pin1> Times remained to input chv1
<pin2> Times remained to input chv2
<puk1> Times remained to input puk1
<puk2> Times remained to input puk2
Reference Note

6.2.4 AT+CMIC Change the Microphone Gain Level
AT+CMIC Change the Microphone Gain Level
Response
+CMIC: (list of supported <channel>s),(list of supported <gainlevel>s)
OK
Test Command
AT+CMIC=?
Parameters
See Write Command
Response
+CMIC: (0,<gainlevel>),(1,<gainlevel>),(2,<gainlevel>),(3,<gainlevel>)
OK
Read Command
AT+CMIC?
Parameters
See Write Command
Response
OK
ERROR
Write Command
AT+CMIC=
<channel>,<gainl
evel> Parameters
<channel> 0 main audio handset channel
<gainlevel> int: 0 – 15
0 0dB
1 +1.5dB
2 +3.0 dB
3 +4.5 dB
4 +6.0 dB
5 +7.5 dB
6 +9.0 dB
7 +10.5 dB
8 +12.0 dB
9 +13.5 dB
10 +15.0 dB
11 +16.5 dB
12 +18.0 dB
13 +19.5 dB
14 +21.0 dB
15 +22.5 dB
Reference Note
Please refer to actual model for channel number.

6.2.5 AT+CALA Set Alarm Time
AT+CALA Set Alarm Time
Response:
+CALA: ("yy/mm/dd,hh:mm:ss","hh:mm:ss"),(1-5),(0-7)
OK
+CME ERROR: <err>
Test Command
AT+CALA=?
Parameters
See Write Command
Response:
+CALA: <time>,<n1>,[<recurr>]
(<CR><LF> +CALA: <time>,<n2>,[<recurr>] …)
OK
+CME ERROR: <err>
Read
Command
AT+CALA?
Parameters
See Write Command
Response
OK
+CME ERROR: <err>
Write
Command
AT+CALA=
<time>,<n>,[<
recurr>] Parameters
<time> a string parameter(string should be included in quotation marks)
which indicates the time when alarm arrives. The format is
"yy/MM/dd,hh:mm:ss" where characters indicate the last two digits
of year, month, day, hour, minute, second and time zone. The time
zone is expressed in quarters of an hour between the local time and
GMT, ranging from -48 to +48.
<n> index of the alarm (range 1 to 5 for now).
<recurr> "0", "1"---"7" string type value indicating day of week for the
alarm in one of the following formats:
"<1..7>[,<1..7>[…]]" – Set a recurrent alarm for one or more days
in the week. The digits 1 to 7 correspond to the days in the week,
Monday (1), …, Sunday (7).
Example: The string "1,2,3,4,5" may be used to set an alarm for
all weekdays.
"0" – Set a recurrent alarm for all days in the week
Reference Note

6.2.6 AT+CALD Delete Alarm
AT+CALD Delete Alarm
Response:
+CALD: (list of supported <n>s)
OK
Test Command
AT+CALD=?
Parameter
See Write Command
Response
OK
+CME ERROR: <err>
Write Command
AT+CALD=<n>
Parameter
<n> integer type value indicating the index of the alarm; default
is manufacturer specific (range 1 to 5 now).
Reference Note
6.2.7 AT+CADC Read ADC
AT+CADC Read ADC
Response:
+CADC: (list of supported <status>s),(list of supported <value>s)
OK
Test Command
AT+CADC=?
Parameters
<status> 1 success
0 fail
<value> integer 0-2800
Response:
+CADC: <status>,<value>
OK
Read Command
AT+CADC?
Parameters
See Test Command
Reference Note
6.2.8 AT+CSNS Single Numbering Scheme
AT+CSNS Single Numbering Scheme
Test Command
AT+CSNS =?
Response
+CSNS: (list of supported <mode>s)

OK
Parameter
See Write Command
Response
+CSNS: <mode>
OK
Read Command
AT+CSNS?
Parameter
See Write Command
Response
OK
ERROR
Write Command
AT+CSNS=<mo
de>
Parameter
<mode>
0 voice
2 fax
4 data
Reference Note
6.2.9 AT+CDSCB Reset Cell Broadcast
AT+CDSCB Reset Cell Broadcast
Execution
Command
AT+CDSCB
Response
OK
Reference Note
Please also refer to AT+CSCB.
6.2.10 AT+CMOD Configure Alternating Mode Calls
AT+CMOD Configure Alternating Mode Calls
Response
+CMOD: (0)
OK
Test Command
AT+CMOD =?
Parameter
See Write Command
Read Command
AT+CMOD?
Response
+CMOD: <mode>

OK
Parameter
See Write Command
Response
OK
ERROR
Write Command
AT+CMOD=[<m
ode>]
Parameter
<mode> 0 Only single mode is supported
Reference Note
6.2.11 AT+CFGRI Indicate RI When Using URC
AT+CFGRI Indicate RI When Using URC
Response
+CFGRI: <status>
OK
Read Command
AT+CFGRI?
Parameter
See Write Command
Response
OK
ERROR
Write Command
AT+CFGRI=<st
atus>
Parameter
<status> 1 on
0 off
Reference Note
6.2.12 AT+CLTS Get Local Timestamp
AT+CLTS Get Local Timestamp
Test Command
AT+CLTS=?
Response
+CLTS: "yy/MM/dd,hh:mm:ss+/-zz"
OK
Response
OK
ERROR
Write Command
AT+CLTS=
<mode>
Parameter
<mode>

0 disable
1 enable
When "get local timestamp” function is enabled, the following URC may
be reported if network sends the message to the MS to provide the MS
with subscriber specific information.
1. Refresh network name by network:
*PSNWID: "<mcc>", "<mnc>”, "<full network name>", <full
network name CI>, "<short network name>",<short
network name CI>
2. Refresh time and time zone by network:
This is UTC time, the time queried by AT+CCLK command is local
time.
*PSUTTZ: <year>, <month>, <day>, <hour>, <min>, <sec>, "<time
zone>", <dst>
3. Refresh network time zone by network:
+CTZV: "<time zone>"
4. Refresh Network Daylight Saving Time by network:
DST: <dst>
Parameters
<mcc> string type; mobile country code
<mnc> string type; mobile network code
<full network name> string type; name of the network in full length.
<full network name CI> integer type; indicates whether to add CI.
0 The MS will not add the initial letters of the Country's
Name to the text string.
1 The MS will add the initial letters of the Country's
Name and a separator (e.g. a space) to the text string.
<short network name> string type; abbreviated name of the network
<short network name CI> integer type; indicates whether to add CI.
0 The MS will not add the initial letters of the Country's
Name to the text string.
1 The MS will add the initial letters of the Country's
Name and a separator (e.g. a space) to the text string.
<year> 4 digits of year (from network)
<month> month (from network)
<day> day (from network)
<hour> hour (from network)
<min> minute (from network)

<sec> second (from network)
<time zone> string type; network time zone. If the network time zone
has been adjusted for Daylight Saving Time, the network
shall indicate this by including the <dst> (Network
Daylight Saving Time)
<dst> Network Daylight Saving Time; the content of this
indicates the value that used to adjust the network time
zone
0 No adjustment for Daylight Saving Time
1 +1 hour adjustment for Daylight Saving
2 +2 hours adjustment for Daylight Saving Time
3 Reserved
Reference Note
Support for this Command will be network dependent.
Set AT+CLTS=1, it means user can receive network time updating
and use AT+CCLK to show current time.
6.2.13 AT+CEXTHS External Headset Jack Control
AT+CEXTHS External Headset Jack Control
Response
+CEXTHS: (<mode>s)
OK
Test Command
AT+CEXTHS=?
Parameter
See Write Command
Response
+CEXTHS: <mode>,<headset attach>
OK
Read Command
AT+CEXTHS?
Parameters
See Write Command
Response
OK
ERROR
+CME ERROR: <err>
Unsolicited result code:
+CEXTHS: <mode>,<headset attach>
Write Command
AT+CEXTHS=<
mode>
Parameters
<mode> a numeric parameter which indicates whether an unsolicited
event code (indicating whether the headset has been

attached/detached) should be sent to the terminal.
0 not send unsolicited event code
1 send unsolicited event code
<headset attach> a numeric parameter which indicates whether a
headset has been attached or not
0 not attached
1 attached
Reference Note
This command is related to the actual module.
6.2.14 AT+CEXTBUT Headset Button Status Reporting
AT+CEXTBUT Headset Button Status Reporting
Response
+CEXTBUT: (list of supported <mode>s)
OK
Test Command
AT+CEXTBUT=
?
Parameter
See Write Command
Response
+CEXTBUT: <mode>,<headset button press>
OK
Read Command
AT+CEXTBUT?
Parameters
See Write Command
Response
OK
ERROR
+CME ERROR: <err>
+CEXTBUT: <mode>,<headset button press>
Write Command
AT+CEXTBUT=
<mode>
Parameters
<mode> a numeric parameter which indicates whether an unsolicited
event code (indicating whether the headset button has been
pressed) should be sent to the terminal.
0 not send unsolicited event code
1 send unsolicited event code
<headset button press> a numeric parameter which indicates
whether a headset button has been pressed or not
0 not pressed
1 pressed

Reference Note
6.2.15 AT+CSMINS SIM Inserted Status Reporting
AT+CSMINS SIM Inserted Status Reporting
Response
+CSMINS: (list of supported <n>s)
OK
Test Command
AT+CSMINS=?
Parameter
See Write Command
Response
+CSMINS: <n>,<SIM inserted>
OK
Read Command
AT+CSMINS?
Parameters
See Write Command
Response
OK
ERROR
+CME ERROR: <err>
Unsolicited result code:
+CSMINS:<n>,<SIM inserted>
Write Command
AT+CSMINS=<
n>
Parameters
<n> a numeric parameter to show an unsolicited event code
indicating whether the SIM has been inserted or removed.
0 disable
1 enable
<SIM inserted> a numeric parameter which indicates whether SIM
card has been inserted.
0 not inserted
1 inserted
Reference Note
6.2.16 AT+CLDTMF Local DTMF Tone Generation
AT+CLDTMF Local DTMF Tone Generation
Test Command
AT+CLDTMF=?
Response
+CLDTMF: (1-100),(0-9,A,B,C,D,*,#)

OK
Response
OK
ERROR
Write Command
AT+CLDTMF=<
n>[,<DTMF
string>] Parameters
<n> a numeric parameter(1-100) which indicates the duration of all
DTMF tones in <DTMF -string> in 1/10 secs
<DTMF -string> a string parameter (string should be included in
quotation marks) which has a max length of 20 chars of form
<DTMF>, separated by commas.
<DTMF> A single ASCII chars in the set 0-9,#,*,A-D.
Execution
Command
AT+CLDTMF
Response
OK
Abort any DTMF tone currently being generated and any DTMF tone
sequence.
Reference Note
6.2.17 AT+CDRIND CS Voice/Data Call Termination Indication
AT+CDRIND CS Voice/Data Call Termination Indication
Response
+CDRIND: (list of supported <n>s)
OK
Test Command
AT+CDRIND=?
Parameter
See Write Command
Response
+CDRIND: <n>
OK
Read Command
AT+CDRIND?
Parameter
See Write Command
Response
OK
ERROR
Parameter
<n> a numeric parameter to enable an unsolicited event code
indicating whether a CS voice call, CS data has been
terminated.
0 disable
1 enable
Write Command
AT+CDRIND=<
n>

When enabled, an unsolicited result code is returned after the connection
has been terminated
+CDRIND: <type>
Parameter
<type> connection type
0 CSV connection
1 CSD connection
2 PPP connection
Reference Note
6.2.18 AT+CSPN Get Service Provider Name from SIM
AT+CSPN Get Service Provider Name from SIM
Response:
+CSPN: <spn>,<display mode>
OK
+CME ERROR: <err>
Read Command
AT+CSPN?
Parameters
<spn> string type(string should be included in quotation
marks); service provider name on SIM
<display mode> 0 not display PLMN. Already registered on PLMN
1 display PLMN
Reference Note
CME errors occur if SIM is not inserted.
6.2.19 AT+CCVM Get and Set the Voice Mail Number on the SIM
AT+CCVM Get and Set the Voice Mail Number on the SIM
Response
+CCVM: maximum length of field <vm number>[, maximum length of
field <alpha string>]
OK
Test Command
AT+CCVM=?
Parameters
See Write Command
Read Command
AT+CCVM?
Response
If voice mail number is not set:
OK
If voice mail number is set:
+CCVM: <vm number>[,<alpha string>]

OK
Parameters
See Write Command
Response
OK
ERROR
+CME ERROR: <err>
Write Command
AT+CCVM=<vm
number>[,<alpha
string>]
Parameters
<vm number> string type (string should be included in quotation
marks) -The voice mail number to write to the SIM
<alpha string> string type (string should be included in quotation
marks) -The alpha-string to write to the SIM
Reference Note
6.2.20 AT+CBAND Get and Set Mobile Operation Band
AT+CBAND Get and Set Mobile Operation Band
Response
+CBAND: (list of supported <op_band>s)
OK
Test Command
AT+CBAND=?
Parameter
See Write Command
Response
+CBAND: <op_band>[,<ALL_BAND>]
OK
Read Command
AT+CBAND?
Parameter
See Write Command
Response
OK
+CME ERROR: <err>
Write Command
AT+CBAND=<o
p_band>
Parameter
<op_band> A string parameter which indicate the operation band.
And the following strings should be included in quotation
marks.
PGSM_MODE

DCS_MODE
PCS_MODE
EGSM_DCS_MODE
GSM850_PCS_MODE
ALL_BAND
Reference Note
Radio settings are stored in non-volatile memory.
6.2.21 AT+CHF Configure Hands Free Operation
AT+CHF Configure Hands Free Operation
Response
+CHF: (list of supported <ind>s),( list of supported <state>s)
OK
Test Command
AT+CHF=?
Parameters
See Write Command
Response
+CHF: <ind>,<state>
OK
Read Command
AT+CHF?
Parameters
See Write Command
Response
OK
ERROR
+CME ERROR: <err>
Write Command
AT+CHF=<in
d>[,<state>]
Parameters
<ind> 0 Unsolicited result code disabled
1 Unsolicited result code enabled
(non-volatile)
<state> 0 main audio handset channel
(volatile)
Reference Note
6.2.22 AT+CHFA Swap the Audio Channels
AT+CHFA Swap the Audio Channels

Test Command
AT+CHFA=?
Response
+CHFA: (0 = NORMAL_AUDIO, 1 = HEADSET_AUDIO, 2 =
HANDFREE_AUDIO, 3 = HEADSET_HANDFREE_AUDIO)
OK
Response
+CHFA: <n>
OK
Read Command
AT+CHFA?
Parameter
See Write Command
Response
OK
+CME ERROR: <err>
Write Command
AT+CHFA=<n>
Parameter
<n> 0 main audio handset channel
Reference Note
This Command swaps the audio channels among different channels.
6.2.23 AT+CSCLK Configure Slow Clock
AT+CSCLK Configure Slow Clock
Response
+CSCLK: (list of supported <n>s)
OK
Test Command
AT+CSCLK=?
Parameter
See Write Command
Response
+CSCLK: <n>
OK
Read Command
AT+CSCLK?
Parameter
See Write Command
Write Command
AT+CSCLK
Response
OK

ERROR=<n>
Parameter
<n> 0 disable slow clock, module will not enter sleep mode.
1 enable slow clock, it is controlled by DTR. When DTR is
high, module can enter sleep mode. When DTR changes to
low level, module can quit sleep mode.
2 The module decides by itself when it enters sleep mode.
When there is no data on serial port, module can enter sleep
mode. Otherwise, it will quit sleep mode.
Reference Note
6.2.24 AT+CENG Switch On or Off Engineering Mode
AT+CENG Switch On or Off Engineering Mode
Response
TA returns the list of supported modes.
+CENG: (list of supported <mode>s),(list of supported <Ncell>s)
OK
Test Command
AT+CENG=?
Parameters
See Write Command
Read Command
AT+CENG?
Response
Engineering Mode is designed to allow a field engineer to view and test the
network information received by a handset, when the handset is either in
idle mode or dedicated mode (that is: with a call active). In each mode, the
engineer is able to view network interaction for the "serving cell" (the cell
the handset is currently registered with) or for the neighboring cells.
TA returns the current engineering mode. The network information
including serving cell and neighboring cells are returned only when
<mode>=1 or <mode> = 2. <cell> carry with them corresponding network
interaction.
+CENG: <mode>,<Ncell>
[+CENG:
<cell>,"<arfcn>,<rxl>,<rxq>,<mcc>,<mnc>,<bsic>,<cellid>,<rla>,<txp
>,<lac>,<TA>"
<CR><LF>+CENG:
<cell>,"<arfcn>,<rxl>,<bsic>,[<cellid>,]<mcc>,<mnc>,<lac>"…]

OK
if <mode>=3
+CENG: <mode>,<Ncell>
[+CENG: <cell>,<mcc>,<mnc>,<lac>,<cellid>,<bsic>,<rxl>
<CR><LF>+CENG: <cell>,<mcc>,<mnc>,<lac>,<cellid>,
<bsic>,<rxl>…]
OK
Parameters
See Write Command
Response
Switch on or off engineering mode. It will report +CENG: (network
information) automatically if <mode>=2.
OK
ERROR
Write Command
AT+CENG
=<mode>[,<Ncell
>]
Parameters
<mode> 0 switch off engineering mode
1 switch on engineering mode
2 switch on engineering mode, and activate the
URC report of network information
3 switch on engineering mode, with limited URC report
<Ncell> 0 un-display neighbor cell ID
1 display neighbor cell ID
If <mode> =3, ignore this parameter.
<cell> 0 the serving cell
1-6 the index of the neighboring cell
<arfcn> absolute radio frequency channel number
<rxl> receive level
<rxq> receive quality
<mcc> mobile country code
<mnc> mobile network code
<bsic> base station identity code
<cellid> cell id
<lac> location area code
<rla> receive level access minimum
<txp> transmit power maximum CCCH
<TA> Timing Advance
Reference Note

6.2.25 AT+SCLASS0 Store Class 0 SMS to SIM When Received Class 0 SMS
AT+SCLASS0 Store Class 0 SMS to SIM When Module Received Class 0 SMS
Response
+SCLASS0: (0, 1)
OK
Test Command
AT+SCLASS0=?
Parameter
See Write Command
Response
+SCLASS0: <mode>
OK
Read Command
AT+SCLASS0?
Parameter
See Write Command
Response
OK
ERROR
Write Command
AT+SCLASS0=<
mode>
Parameter
<mode>
0 disable to store Class 0 SMS to SIM when module receives Class
0 SMS
1 enable to store Class 0 SMS to SIM when module receives Class
0 SMS
Reference Note
6.2.26 AT+CCID Show ICCID
AT+CCID Show ICCID
Test Command
AT+CCID =?
Response:
OK
Execution
Command
AT+CCID
Response:
Ccid data [ex. 898600810906F8048812]
OK
Reference Note
6.2.27 AT+CMTE Set Critical Temperature Operating Mode or Query Temperature
AT+CMTE Set Critical Temperature Operating Mode or Query Temperature

+CMTE: <mode><Temperature>
OK
AT+CMTE?
Parameters
See Write Command
Response
OK
ERROR
Write Command
AT+CMTE=
<mode>
Parameters
<mode>
0 disable temperature detection
1 enable temperature detection
<Temperature> range of -40 to 90
Reference Note
When temperature is extremely high or low, product will power off.
URCs indicating the alert level "1" or "-1" are intended to enable the
user to take appropriate precautions, such as protecting the module
from exposure to extreme conditions, or saving or backing up data etc.
Level "2" or "-2" URCs are followed by immediate shutdown.
6.2.28 AT+CBTE Battery Temperature Query
AT+CBTE Battery Temperature Query
Response:
+CBTE: <voltage>
OK
Read Command
AT+CBTE ?
Parameter
<voltage> battery voltage(mV)
Reference Note
Only supported in SIM900D
The temperature can be calculated according to the resistance of NTC
and the voltage supported by this command.
6.2.29 AT+CSDT Switch On or Off Detecting SIM Card
AT+CSDT Switch On or Off Detecting SIM Card
Response
+CSDT: (0-1)
OK
Test Command
AT+CSDT =?
Parameter

See Write Command
Response
+CSDT: <mode>
OK
Read Command
AT+CSDT?
Parameter
See Write Command
Response
OK
ERROR
Write Command
AT+CSDT=<mo
de>
Parameter
<mode>
0 switch off detecting SIM card
1 switch on detecting SIM card
Reference Note
It is not supported temporarily.
6.2.30 AT+CMGDA Delete All SMS
AT+CMGDA Delete All SMS
Response:
+CMGDA: (list of supported <type>s)
OK
+CMS ERROR: <err>
Test Command
AT+CMGDA=?
Parameter
See Write Command
Response:
OK
ERROR
+CMS ERROR: <err>
Write Command
AT+CMGDA=<t
ype>
Parameter
<type>
1) If text mode:
"DEL READ" delete all read messages
"DEL UNREAD" delete all unread messages
"DEL SENT" delete all sent SMS
"DEL UNSENT" delete all unsent SMS
"DEL INBOX" delete all received SMS
"DEL ALL" delete all SMS
2) If PDU mode:
1 delete all read messages

2 delete all unread messages
3 delete all sent SMS
4 delete all unsent SMS
5 delete all received SMS
6 delete all SMS
Reference Note
6.2.31 AT+STTONE Play SIM Toolkit Tone
AT+STTONE Play SIM Toolkit Tone
Response
+STTONE: (list of supported <mode>s),(list of supported <tone>s),(list of
supported <duration>s)
OK
+CME ERROR: <err>
Test Command
AT+STTONE=?
Parameters
See Write Command
Response
OK
+CME ERROR: <err>
Write Command
AT+STTONE=<
mode>,<tone>,<
duration>
Parameters
<mode> 0 Stop playing tone
1 Start playing tone
<tone> numeric type
1 Dial Tone
2 Called Subscriber Busy
3 Congestion
4 Radio Path Acknowledge
5 Radio Path Not Available / Call Dropped
6 Error / Special information
7 Call Waiting Tone
8 Ringing Tone
16 General Beep
17 Positive Acknowledgement Tone
18 Negative Acknowledgement or Error Tone
19 Indian Dial Tone
20 American Dial Tone
<duration> numeric type, in milliseconds.
Max requested value = 255*60*1000 = 15300000ms

(supported range = 3- 15300000)
Reference Note
The default <tone>, if none is entered, it should be General Beep.
The default <duration>, if none is entered, it should be 500ms.
6.2.32 AT+SIMTONE Generate Specifically Tone
AT+SIMTONE Generate Specifically Tone
Response
+SIMTONE: (0,1),(20-20000),(200-25500),(0,100-25500),(0-500000)
OK
Test Command
AT+SIMTONE
=?
Parameters
See Write Command
Response
OK
+CME ERROR: <err>
Write Command
AT+SIMTONE
=<mode>,<frequ
ency>,<periodO
n>,<periodOff>[,
<duration>]
Parameters
<mode> 0 Stop playing tone
1 Start playing tone
<frequency> the frequency of tone to be generated
<periodOn> the period of generating tone, must be multiple of 100
<periodOff> the period of stopping tone, must be multiple of 100
<duration> duration of tones in milliseconds
Reference Note
6.2.33 AT+CCPD Enable or Disable Alpha String
AT+CCPD Enable or Disable Alpha String
Response
+CCPD: (0,1)
OK
Test Command
AT+CCPD=?
Parameter
See Write Command
Response
+CCPD: <mode>
OK
Read Command
AT+CCPD?
Parameter
See Write Command

Response
OK
+CME ERROR: <err>
Write Command
AT+CCPD=<mo
de>
Parameter
<mode>
0 disable to present alpha string
1 enable to present alpha string
Reference Note
6.2.34 AT+CGID Get SIM Card Group Identifier
AT+CGID Get SIM Card Group Identifier
Response
+GID: <gid1> <gid2>
OK
+CME ERROR: <err>
Execution
Command
AT+CGID
Parameters
<gid1> integer type of SIM card group identifier 1
<gid2> integer type of SIM card group identifier 2
Reference Note
If the SIM supports GID files, the GID values will be retuned. Otherwise
0xff is retuned.
6.2.35 AT+MORING Show State of Mobile Originated Call
AT+MORING Show State of Mobile Originated Call
Response
+MORING: (0,1)
OK
Test Command
AT+MORING=?
Parameter
See Write Command
Response
+MORING: <mode>
OK
Read Command
AT+MORING?
Parameter
See Write Command
Write Command Response

OK
+CME ERROR: <err>
Parameter
<mode> 0 not show call state of mobile originated call
1 show call state of mobile originated call. After the call
number is dialed, the URC strings of MO RING will be
sent if another call is alerted and the URC strings of MO
CONNECTED will be sent if the call is established.
AT+MORING
=<mode>
MO RING
the call is alerted.
MO CONNECTED
the call is established.
Reference Note
6.2.36 AT+CMGHEX Enable or Disable Sending Non-ASCII Character SMS
AT+CMGHEX Enable or Disable Sending Non-ASCII Character SMS
Response
+CMGHEX: (list of supported <mode>s)
OK
Test Command
AT+CMGHEX
=?
Parameter
See Write Command
Response
+CMGHEX: <mode>
OK
Read Command
AT+CMGHEX?
Parameter
See Write Command
Response
OK
+CME ERROR: <err>
Write Command
AT+CMGHEX
=<mode>
Parameter
<mode> 0 Send SMS in ordinary way
1 Enable to send SMS varying from 0x00 to 0x7f except
0x1a and 0x1b under text mode and GSM character set

Reference Note
Only be available in TEXT mode and AT+CSCS="GSM".
6.2.37AT+AUTEST Audio Channel Loopback Test
AT+AUTEST Audio Channel Loopback Test
Response
+AUTEST: (0-1),(0-1)
OK
Test Command
AT+AUTEST=?
Parameter
See Write Command
Response
OK
+CME ERROR: <err>
Write Command
AT+AUTEST=
<state>,<type>
Parameters
<state> 0 test is off
1 test is on
<type> 0 Normal audio channel
1 AUX audio channel
Reference Note
6.2.38AT+CCODE Configure SMS Code Mode
AT+CCODE Configure SMS Code Mode
Response
+CCODE: (0,1)
OK
Test Command
AT+CCODE=?
Parameter
See Write Command
Response
+CCODE:<mode>
OK
Read Command
AT+CCODE?
Parameter
See Write Command
Write Command
AT+CCODE=
<mode>
Response
OK
+CME ERROR: <err>

Parameter
<mode> 0 code mode compatible with NOKIA
1 code mode compatible with SIEMENS
Reference Note
6.2.39 AT+CIURC Enable or Disable Initial URC Presentation
AT+CIURC Enable or Disable Initial URC Presentation
Response
+CIURC: (0,1)
OK
Test Command
AT+CIURC=?
Parameter
See Write Command
Response
+CIURC:<mode>
OK
Read Command
AT+CIURC?
Parameter
See Write Command
Response
OK
+CME ERROR: <err>
Write Command
AT+CIURC=
<mode>
Parameter
<mode> 0 disable URC presentation.
1 enable URC presentation
Reference Note
When module is powered on andinitialization procedure is over.
URC "Call Ready" will be presented if <mode> is 1.
6.2.40 AT+CPSPWD Change PS Super Password
AT+CPSPWD Change PS Super Password
Response
OK
+CME ERROR: <err>
Write Command
AT+CPSPWD=
<oldpwd>,<newp
wd>
Parameters
<oldpwd> string type(string should be included in quotation marks).

Old password and length should be 8.
<newpwd> string type(string should be included in quotation marks).
New password and length should be 8.
Reference Note
Default value of <oldpwd> is "12345678".
If module is locked to a specific SIM card through AT+CLCK and
password lost or SIM state is PH-SIM PUK, user can use the super
password to unlock it.
It is not supported temporarily.
6.2.41 AT+EXUNSOL Enable or Disable Proprietary Unsolicited Indications
AT+EXUNSOL Enable or Disable Proprietary Unsolicited Indications
Response
+EXUNSOL: (list of supported <exunsol>s)
OK
Test Command
AT+EXUNSOL
=?
Parameters
See Write Command
Response
OK
+CME ERROR: <err>
Write Command
AT+EXUNSOL=
<exunsol>,<mod
e>
Parameters
<exunsol> string type(string should be included in quotation marks).
values are currently reserved by the present document
"SQ" Signal Quality Report
Displays signal strength and channel bit error rate (similar
To AT+CSQ) in form +CSQN: <rssi>,<ber>when values change.
<mode>
0 disable
1 enable
2 query
Reference Note
6.2.42 AT+CGMSCLASS Change GPRS Multislot Class
AT+CGMSCLASS Change GPRS Multislot Class

Response
MULTISLOT CLASS: (4,8,9,10)
OK
Test Command
AT+CGMSCLA
SS=?
Parameter
See Write Command
Response
MULTISLOT CLASS: <class>
OK
Read Command
AT+CGMSCLA
SS?
Parameter
See Write Command
Response
OK
+CME ERROR: <err>
Write Command
AT+CGMSCLA
SS=<class>
Parameter
<class> GPRS multi-slot class
Reference Note
6.2.43 AT+CDEVICE View Current Flash Device Type
AT+CDEVICE View Current Flash Device Type
Read Command
AT+CDEVICE?
Response
Device Name: (Current flash device type)
OK
Reference
V.25ter
Note
6.2.44 AT+CCALR Call Ready Query
AT+CCALR Call Ready Query
Response
+CCALR: (list of supported <mode>s)
OK
Test Command
AT+CCALR=?
Parameter
<mode> a numeric parameter which indicates whether the module is

ready for phone call.
0 module is not ready for phone call
1 module is ready for phone call
Response
ME returns the status of result code presentation and an integer <n>
which shows whether the module is currently ready for phone call.
+CCALR: <mode>
OK
Read Command
AT+CCALR?
Parameter
<mode>
See Test Command
Reference Note
6.2.45 AT+GSV Display Product Identification Information
AT+GSV Display Product Identification Information
Execution
Command
AT+GSV
Response
TA returns product information text
Example:
SIMCOM_Ltd
SIMCOM_SIM900
Revision: 1137B01V01SIM900M32_ST
OK
Reference Note
6.2.46 AT+SGPIO Control the GPIO
AT+ SGPIO Control the GPIO
Response
+SGPIO: (0-1),(1-12),(0-2),(0-1)
OK
Test Command
AT+SGPIO=?
Parameters
See Write Command
Response
OK
ERROR
Write Command
AT+SGPIO=<ope
ration>,<GPIO>,
<function>,<level
>
Parameters

<Operation> 0 set the GPIO function including the GPIO output and
GPIO as the Keypad.
1 read the GPIO level. Please note that only when the
gpio is set as input, user can use parameter 1 to read
the GPIO level, otherwise the module will return
"ERROR".
<GPIO> the GPIO you want to be set. ( it has relations with the
hardware, Please refer to the hardware manual)
<function> Only when <Operation> is set to 0, this option takes
effect.
0 set the GPIO to input.
1 set the GPIO to output
2 set the GPIO to keypad
<level> 0 set the GPIO low level
1 set the GPIO high level
Reference Note
Only GPIO1, GPIO2, GPIO3, GPIO4, GPIO6, GPIO7, GPIO8, GPIO9 can
be used as Keypad. And if one of them is set to gpio function, others will
be set to GPIO output and low level automatically.
6.2.47 AT+SPWM Generate the Pulse-Width-Modulation
AT+SPWM Generate the Pulse-Width-Modulation
Response
+SPWM: (list of supported <index>s ),( list of supported <period>s),( list
of supported <level>s)
OK
Test Command
AT+SPWM=?
Parameters
See Write Command
Response
OK
+CME ERROR: <err>
Write Command
AT+SPWM=<in
dex>,<period>,
<level>
Parameters
<index> integer type: the index number of PWM port, which value is
0-2;
0: for buzzer (according to the hardware support or not).
1: corresponding to PWM_OUT0 in the hardware circuit
2: corresponding to PWM_OUT1 in the hardware circuit
<period> The range of <period> is 0-126 if <index> is set to 1 or 2,
the range of <period> is 0-65535 if <index> is set to 0,

the output frequency equals to (26MHz/8)/(period+1).
<level> 0-100: tone level, which can be converted to duty ratio.
Reference Note
We have a 26MHz crystal oscillator. The MAX frequency of PWM is
26/8=3.25Mhz.
The equation of final frequency and <period> is this: frequency
=3.25/(period+1), for example, if <period> is set to 100, we get a
frequency: 3.25/101 = 32.178Khz.
The equation of <level> and duty factor is: duty factor = (level+1).
6.2.48 AT+ECHO Echo Cancellation Control
AT+ECHO Echo Cancellation Control
Response
+ECHO: MIC:(list of supported <mic>s), ES:( list of supported <es>s),
SES:(list of supported <ses>s), MODE:(list of supported <mode>s)
OK
Test Command
AT+ECHO=?
Parameters
See Write Command
Response
+ECHO: (0, <es>, <ses>, <mode>),(1, <es>, <ses>, <mode>),(2, <es>,
<ses>, <mode>),(3, <es>, <ses>, <mode>)
OK
Read Command
AT+ECHO?
Parameters
See Write Command
Response
OK
+CME ERROR: <err>
Write Command
AT+ECHO=
<mic>,<es>[,<ses
>[,<mode>]]
Parameters
<mic> audio channel
0 main audio handset channel
<es> echo suppression
0-8 (when mic=0or1 default value is 0; when mic=2 or 3 default
value is 7 ) the bigger the value, the stronger the restraint.
<ses> selective echo suppression

0-6 (when mic=0 or1 default value is 0; when mic=2 or 3 default
value is 5)
<mode> 0 close echo algorithm
1 open echo algorithm
Reference Note
For this command, please refer to actual model.
6.2.49 AT+CAAS Control Auto Audio Switch
AT+CAAS Control Auto Audio Switch
Response
+CAAS: (0-2)
OK
Test Command
AT+CAAS=?
Parameter
See Write Command
Response
+CAAS: <mode>
OK
Read Command
AT+CAAS?
Parameter
See Write Command
Response
This parameter setting determines whether or not the audio channel will be
switched automatically to the corresponding channel in case of headset
attaching or detaching.
OK
+CME ERROR: <err>
Write Command
AT+CAAS=
<mode>
Parameter
<mode>
0 disable automatic audio channel switch function, the headset
HOOK function is disabled;
1 enable automatic audio channel switch function, the headset
HOOK function is enabled;
2 disable automatic audio channel switch function, the headset
HOOK function is enabled.
Reference Note
For this command, please refer to actual model.
The headset detection is still worked when <mode> is set to 0. In other

word, if "AT+CEXTHS=1" is set, the unsolicited event code
(indicating whether the headset has been attached/detached) will be
sent to the terminal.
6.2.50 AT+SVR Configure Voice Coding Type for Voice Calls
AT+SVR Configure Voice Coding Type for Voice Calls
Response
+SVR: (list of supported <voice_rate_coding>s)
OK
Test Command
AT+SVR=?
Parameter
See Write Command
Response
+SVR: <voice_rate_coding>
OK
Read Command
AT+SVR?
Parameter
See Write Command
Response
OK
+CME ERROR: <error>
Write Command
AT+SVR=<voice
_rate_coding>
Parameter
<voice_rate_coding> A number parameter which indicate the voice
coding type.
0:FR
1:EFR / FR
2.FR / HR
3:FR / HR
4:HR /EFR
5:EFR/ HR
6:AMR-FR/EFR,AMR-HR
7:AMR-FR/EFR,AMR-HR/HR
8:AMR-HR/ HR/AMR-FR/EFR
9:AMR-HR/AMR-FR/EFR
10:AMR-HR/AMR-FR/FR
11:AMR-HR/HR/AMR-FR
12:AMR-FR/AMR-HR
13:AMR-FR/FR/AMR-HR
14:AMR-FR/FR/AMR-HR/HR
15:AMR-FR/EFR/FR/AMR-HR/HR
16:AMR-HR/ AMR-FR /EFR/FR/HR (default value)

Reference Note
The parameter of AT+SVR is stored in non-volatile memory.
6.2.51 AT+GSMBUSY Reject Incoming Call
AT+GSMBUSY Reject Incoming Call
Response
+GSMBUSY: (0,1)
OK
Test Command
AT+GSMBUSY=
?
Parameter
See Write Command
Response
+GSMBUSY: <mode>
OK
Read Command
AT+GSMBUSY?
Parameter
See Write Command
Response
OK
+CME ERROR: <error>
Write Command
AT+GSMBUSY=
<mode>
Parameter
<mode> 0 enable incoming call
1 forbid incoming call
Reference Note
The parameter is not saved if the module power down.

7 AT Commands for GPRS Support
7.1 Overview of AT Commands for GPRS Support
Command Description
AT+CGATT ATTACH OR DETACH FROM GPRS SERVICE
AT+CGDCONT DEFINE PDP CONTEXT
AT+CGQMIN QUALITY OF SERVICE PROFILE (MINIMUM ACCEPTABLE)
AT+CGQREQ QUALITY OF SERVICE PROFILE (REQUESTED)
AT+CGACT PDP CONTEXT ACTIVATE OR DEACTIVATE
AT+CGDATA ENTER DATA STATE
AT+CGPADDR SHOW PDP ADDRESS
AT+CGCLASS GPRS MOBILE STATION CLASS
AT+CGEREP CONTROL UNSOLICITED GPRS EVENT REPORTING
AT+CGREG NETWORK REGISTRATION STATUS
AT+CGSMS SELECT SERVICE FOR MO SMS MESSAGES
7.2 Detailed Descriptions of AT Commands for GPRS Support
7.2.1 AT+CGATT Attach or Detach from GPRS Service
AT+CGATT Attach or Detach from GPRS Service
Response
+CGATT: (list of supported <state>s)
OK
Test Command
AT+CGATT=?
Parameter
See Write Command
Response
+CGATT: <state>
OK
Read Command
AT+CGATT?
Parameter
See Write Command
Write Command
AT+CGATT=<st
ate>
Response
OK
+CME ERROR: <err>
SIM300_ATC_V1.03 1 08.29.2008

Parameter
<state> indicates the state of GPRS attachment
0 detached
1 attached
Other values are reserved and will result in an ERROR response to the
Write Command.
Reference Note
7.2.2 AT+CGDCONT Define PDP Context
AT+CGDCONT Define PDP Context
Response
+CGDCONT: (range of supported <cid>s),<PDP_type>,,,(list of
supported<d_comp>s),(list of supported<h_comp>s)
[<CR><LF>+CGDCONT:
(range of supported <cid>s), <PDP_type>,,,(list ofsupported
<d_comp>s),(list of supported <h_comp>s) [...]]
OK
Test Command
AT+CGDCONT
=?
Parameters
See Write Command
Response
+CGDCONT:
<cid>,<PDP_type>,<APN>,<PDP_addr>,<data_comp>,<head_comp>
[<CR><LF>+CGDCONT:
<cid>,<PDP_type>,<APN>,<PDP_addr>,<data_comp>,<head_comp>
[…]]
OK
Read Command
AT+CGDCONT
?
Parameters
See Write Command
Response
OK
ERROR
Write Command
AT+CGDCONT
=<cid>[,<PDP_ty
pe>,[APN>[,<PD
P_addr>[,<d_co
mp>[,<h_comp>]
]]]]
Parameters
<cid> (PDP Context Identifier)
1 PDP Context Identifier 1
Definition stored in non-volatile memory

Definition stored in non-volatile memory
Default <cid>
Locked in non-volatile memory and is always defined, it can
not be changed by user.
<PDP_type> (Packet Data Protocol type)
IP Internet Protocol (IETF STD 5)
<APN> (Access Point Name) a string parameter(string should be
included in quotation marks) which is a logical name that is
used to select the GGSN or the external packet data
network. If the value is null or omitted, then the
subscription value will be requested.
<PDP_addr> a string parameter (IP address). Format:
"<n>.<n>.<n>.<n>" where <n>=0..255
If the value is null or equals 0.0.0.0 a dynamic address will
be requested. The allocated address may be read using the
+CGPADDR command
<d_comp> a numeric parameter that controls PDP data compression
0 –PDP data compression off (default if value is omitted)
<h_comp> a numeric parameter that controls PDP data compression
0 –PDP header compression off (default if value is omitted)
Reference Note
7.2.2.1For <cid> 1,2 and 3 the following parameters are stored in non volatile memory:
Parameter name Default value
<cid> 1,2 or 3
Locked 0xFF..0xFF
Defined 0x00
<precedence> 0x00
<delay> 0x00
<reliability> 0x03
<peak> 0x00
<mean> 0x00
<pdp_type> 0x01 (IP)
<APN> 0xFF..0xFF
<PDP_address> 0x00..0x00
<Guaranteed bitrate DL> 0x00
<Guaranteed bitrate UL> 0x00
<Traffic handling priority> 0x00

<Transfer delay> 0x00
<SDU error ratio> 0x00
<Residual bit error ratio> 0x00
<Maximum bitrate DL> 0x00
<Maximum bitrate UL> 0x00
<Maximum SDUsize> 0x00
<Delivery of erroneous SDUs> 0x00
<Delivery order> 0x00
<Traffic class> 0x00
7.2.3 AT+CGQMIN Quality of Service Profile (Minimum Acceptable)
AT+CGQMIN Quality of Service Profile (Minimum Acceptable)
Response
+CGQMIN: <PDP_type>,(list of supported <precedence>s),(list of
supported <delay>s),(list of supported <reliability>s),(list of supported
<peak>s),(list of supported <mean>s)
[<CR><LF>+CGQMIN: <PDP_type>,(list of supported <precedence>
s),(list of supported <delay>s),(list of supported <reliability>s),(list of
supported <peak>s),(list of supported <mean>s)
[…]]
OK
Test Command
AT+CGQMIN=?
Parameters
See Write Command
Response
+CGQMIN: <cid>,<precedence>,<delay>,>reliability>,<peak>,<mean>
[<CR><LF>+CGQMIN:
<cid>,<precedence>,<delay>,<reliability>,<peak>,<mean>
[…]]
OK
Read Command
AT+CGQMIN?
Parameters
See Write Command
Response
OK
+CME ERROR: <err>
Write Command
AT+CGQMIN=<
cid>[,<precedenc
e>[,<delay>[,<rel
iability>[,<peak>
[,<mean>]]]]] Parameters

<cid>
1..3 PDP Context Identifier
Definition stored in non-volatile memory (refer to
+CGDCONT). cid 3 is reserved and is always defined, it
cannot be changed by user.
<precedence>
0 QOS precedence class subscribed value
1..3 QOS precedence class
<delay>
0 QOS delay class subscribed value
1..4 QOS delay class subscribed
<reliability>
0 QOS reliability class subscribed value
1..5 QOS reliability class.
<peak>
0 QOS peak throughput class subscribed value
1..9 QOS peak throughput class
<mean>
0 QOS mean throughput class subscribed value
1..18 QOS mean throughput class
31 QOS mean throughput class best effort
Reference Note
7.2.4 AT+CGQREQ Quality of Service Profile (Requested)
AT+CGQREQ Quality of Service Profile (Requested)
Response
+CGQREQ: <PDP_type>,(list of supported <precedence>s),(list of
supported <delay>s),(list of supported <reliability>s),<list of supported
<peak>s),(list of supported <mean>s)
[<CR><LF>+CGQREQ: <PDP_type>,(list of supported <precedence>
s),(list of supported <delay>s),(list of supported <reliability>s),(list of
supported <peak>s),(list of supported <mean>s)
[…]]
OK
Test Command
AT+CGQREQ=?
Parameters
See Write Command
Read Command
AT+CGQREQ?
Response
+CGQREQ: <cid>,<precedence>,<delay>,>reliability>,<peak>,<mean>

[<CR><LF>+CGQREQ:
<cid>,<precedence>,<delay>,<reliability>,<peak>,<mean>
[…]]
OK
Parameters
See Write Command
Response
OK
+CME ERROR: <err>
Write Command
AT+CGQREQ=
<cid>[,<precede
nce>[,<delay>[,<
reliability>[,<pea
k>[,<mean>]]]]] Parameters
<cid> a numeric parameter which specifies a particular PDP context
definition (see +CGDCONT Command)
1..3 Definition stored in non-volatile memory (refer to
+CGDCONT) cid 3 is reserved and is always defined, it
cannot be changed by user.
The following parameter are defined in GSM 03.60
<precedence> a numeric parameter which specifies the precedence class
0 QOS precedence class subscribed value
1..3 QOS precedence class
<delay> a numeric parameter which specifies the delay class
0 QOS delay class subscribed value
1..4 QOS delay class
<reliability> a numeric parameter which specifies the reliability class
0 QOS reliability class subscribed value
1..5 QOS reliability class; default value: 3
<peak> a numeric parameter which specifies the peak throughput
class
0 QOS peak throughput class subscribed value
1..9 QOS peak throughput class
<mean> a numeric parameter which specifies the mean throughput
class
0 QOS mean throughput class subscribed value
1..18 QOS mean throughput class
31 QOS mean throughput class best effort
Reference Note

7.2.5 AT+CGACT PDP Context Activate or Deactivate
AT+CGACT PDP Context Activate or Deactivate
Response
+CGACT: (list of supported <state>s)
OK
Test Command
AT+CGACT=?
Parameters
See Write Command
Response
+CGACT: <cid>,<state>[<CR><LF>+CGACT:<cid><state>…]
OK
Read Command
AT+CGACT?
Parameters
See Write Command
Response
OK
+CME ERROR: <err>
Write Command
AT+CGACT=[<s
tate> [,<cid>]]
Parameters
<state> indicates the state of PDP context activation
0 deactivated
1 activated
Other values are reserved and will result in an ERROR
response to the Write Command.
1..3 PDP Context Identifier, cid 3 is reserved and is always
defined, it cannot be changed by user.
Reference Note
This command is used to test PDPs with network simulators.
Successful activation of PDP on real network is not guaranteed.
Refer to AT+CGDATA clarification for more information.
7.2.6 AT+CGDATA Enter Data State
AT+CGDATA Enter Data State
Test Command
AT+CGDATA=?
Response
+CGDATA: list of supported <L2P>s
OK

Parameter
See Write Command
Response
CONNECT
+CME ERROR: <err>
Write Command
AT+CGDATA=<
L2P>,[<cid>]
Parameters
<L2P> a string parameter (string should be included in quotation
marks) that indicates the layer 2 protocol to be used between the
TE and MT:
PPP – Point to Point protocol for a PDP such as IP
Other values are not supported and will result in an ERROR
response to the execution Command.
1..3 PDP Context Identifier. cid 3 is reserved and is always
Reference Note
7.2.7 AT+CGPADDR Show PDPAddress
AT+CGPADDR Show PDPAddress
Response
+CGPADDR: (list of defined <cid>s)
OK
Test Command
AT+CGPADDR=
?
Parameters
See Write Command
Response
+CGPADDR: <cid>,<PDP_addr>
[<CR><LF>+CGPADDR: <cid>,<PDP_addr>[…]]
OK
ERROR
Write Command
AT+CGPADDR=
<cid>
Parameters
definition (see +CGDCONT Command) If <cid> is not specified,

the addresses for all defined contexts will be returned.
1..3 PDP Context Identifier, cid 3 is reserved and is always
<PDP_addr> String type IP address
Format: "<n>.<n>.<n>.<n>" where <n>=0..255
Reference Note
Write command returns address provided by the network if a connection has
been established.
7.2.8 AT+CGCLASS GPRS Mobile Station Class
AT+CGCLASS GPRS Mobile Station Class
Response
+CGCLASS: (list of supported <class>s)
OK
Test Command
AT+CGCLASS=
?
Parameter
See Write Command
Response
+CGCLASS: <class>
OK
Read Command
AT+CGCLASS?
Parameter
See Write Command
Response
OK
ERROR
+CME ERROR: <err>
Write Command
AT+CGCLASS=
<class>
Parameter
<class> a string parameter(string should be included in quotation
marks) which indicates the GPRS mobile class (in
descending order of functionality)
B Class-B mode of operation (A/Gb mode), (not
applicable in Iu mode) MT would operate PS and
CS services but not simultaneously
CC Class-C mode of operation in CS only mode

(A/Gb mode), or CS (Iu mode) (lowest
mode of operation). MT would only operate
CS services
Reference Note
It only supports Class B and CC.
7.2.9 AT+CGEREP Control Unsolicited GPRS Event Reporting
AT+CGEREP Control Unsolicited GPRS Event Reporting
Response
+CGEREP: (list of supported <mode>s),(list of supported <bfr>s)
OK
Test Command
AT+CGEREP=?
Parameters
See Write Command
Response
+CGEREP: <mode>,<bfr>
OK
Read Command
AT+CGEREP?
Parameters
See Write Command
Response
OK
ERROR
Write Command
AT+CGEREP=<
mode>[,<bfr>]
Parameters
<mode>
0 Buffer unsolicited result codes in the MT; if MT
result code buffer is full, the oldest ones is discarded.
1 Discard unsolicited result codes when MT TE link
is reserved (e.g. in on line data mode); otherwise
forward them directly to the TE
2 Buffer unsolicited result codes in the MT when MT
TE link is reserved (e.g. in on line data mode) and
flush them to the TE when MT TE link becomes
available; otherwise forward them directly to the TE
<bfr> 0 MT buffer of unsolicited result codes defined within
this command is cleared when <mode> 1 or 2 is
entered

1 MT buffer of unsolicited result codes defined within this
command is flushed to the TE when <mode> 1 or 2
is entered
Reference Note
7.2.10 AT+CGREG Network Registration Status
AT+CGREG Network Registration Status
Response
+CGREG: (list of supported <n>s)
OK
Test Command
AT+CGREG=?
Parameters
See Write Command
Response
+CGREG: <n>,<stat>[,<lac>,<ci>]
OK
+CME ERROR: <err>
Read Command
AT+CGREG?
Parameters
See Write Command
Response
OK
ERROR
Write Command
AT+CGREG=
<n>
Parameters
<n> 0 disable network registration unsolicited result code
1 enable network registration unsolicited result code
+CGREG:<stat>
2 enable network registration and location information
unsolicited result code +CGREG: <stat>[,<lac>,<ci>]
<stat>
0 Not registered, MT is not currently searching an
The GPRS service is disabled, the UE is allowed to attach
for GPRS if requested by the user
1 Registered, home network
2 Not registered, but MT is currently trying to attach or

searching an operator to register to
The GPRS service is enabled, but an allowable PLMN is
currently not available. The UE will start a GPRS
attach as soon as an allowable PLMN is available.
3 Registration denied
The GPRS service is disabled, the UE is not allowed to
attach for GPRS if it is requested by the user.
4 Unknown
5 Registered, roaming
<lac> string type (string should be included in quotation marks); two
byte location area code in hexadecimal format (e.g. "00C3"
equals 195 in decimal)
<ci> string type (string should be included in quotation marks); two
bytes cell ID in hexadecimal format
Reference Note
7.2.11 AT+CGSMS Select Service for MO SMS Messages
AT+CGSMS Select Service for MO SMS Messages
Response
+CGSMS: (list of currently available <service>s)
OK
Test Command
AT+CGSMS=?
Parameter
See Write Command
Response
+CGSMS: <service>
OK
Read Command
AT+CGSMS?
Parameter
See Write Command
Response
OK
+CME ERROR: <err>
Write Command
AT+CGSMS=<se
rvice>
Parameter
<service> a numeric parameter which indicates the service or service
preference to be used
0 Packet Domain

1 Circuit switched
2 Packet Domain preferred (use circuit switched if
GPRS not available)
3 Circuit switched preferred (use Packet Domain if
circuit switched not available)
Reference Note
The circuit switched service route is the default method

8 AT Commands for TCPIP Application Toolkit
8.1 Overview
Command Description
AT+CIPMUX START UP MULTI-IP CONNECTION
AT+CIPSTART START UP TCP OR UDP CONNECTION
AT+CIPSEND SEND DATA THROUGH TCP OR UDP CONNECTION
AT+CIPQSEND SELECT DATA TRANSMITTING MODE
AT+CIPACK QUERY PREVIOUS CONNECTION DATA TRANSMITTING STATE
AT+CIPCLOSE CLOSE TCP OR UDP CONNECTION
AT+CIPSHUT DEACTIVATE GPRS PDP CONTEXT
AT+CLPORT SET LOCAL PORT
AT+CSTT START TASK AND SET APN, USER NAME, PASSWORD
AT+CIICR BRING UP WIRELESS CONNECTION WITH GPRS OR CSD
AT+CIFSR GET LOCAL IP ADDRESS
AT+CIPSTATUS QUERY CURRENT CONNECTION STATUS
AT+CDNSCFG CONFIGURE DOMAIN NAME SERVER
AT+CDNSGIP QUERY THE IP ADDRESS OF GIVEN DOMAIN NAME
AT+CIPHEAD ADD AN IP HEAD AT THE BEGINNING OF A PACKAGE RECEIVED
AT+CIPATS SET AUTO SENDING TIMER
AT+CIPSPRT SET PROMPT OF ‘>’ WHEN MODULE SENDS DATA
AT+CIPSERVER CONFIGURE MODULE AS SERVER
AT+CIPCSGP SET CSD OR GPRS FOR CONNECTION MODE
AT+CIPSRIP SHOW REMOTE IP ADDRESS AND PORT WHEN RECEIVED DATA
AT+CIPDPDP SET WHETHER TO CHECK STATE OF GPRS NETWORK TIMING
AT+CIPMODE SELECT TCPIP APPLICATION MODE
AT+CIPCCFG CONFIGURE TRANSPARENT TRANSFER MODE
AT+CIPSHOWTP DISPLAY TRANSFER PROTOCOL IN IP HEAD WHEN RECEIVED
DATA
AT+CIPUDPMO
DE
UDP EXTENDED MODE
AT+CIPRXGET GET DATA FROM NETWORK MANUALLY
AT+CIPQRCLOS
E
QUICK REMOTE CLOSE
AT+CIPSCONT SAVE TCPIP APPLICATION CONTEXT
SIM300_ATC_V1.03 1 08.29.2008

8.2.1 AT+CIPMUX Start Up Multi-IP Connection
AT+CIPMUX Start Up Multi-IP Connection
Response
+CIPMUX: (0,1)
OK
Test Command
AT+CIPMUX=?
Parameter
See Write Command
Response
+CIPMUX: <n>
OK
Read Command
AT+CIPMUX?
Parameter
See Write Command
Response
OK
Write Command
AT+CIPMUX=<
n>
Parameter
<n> 0 Single IP connection
1 Multi IP connection
Reference Note
Only in IP initial state, AT+CIPMUX=1 is effective;
Only when multi IP connection and GPRS application are both shut
down, AT+CIPMUX=0 is effective.
8.2.2 AT+CIPSTART Start Up TCP or UDP Connection
AT+CIPSTART Start Up TCP or UDP Connection
Test Command
AT+CIPSTART=
?
Response
1) If AT+CIPMUX=0
+CIPSTART: (list of supported <mode>),(<IP address>),(<port>)
+CIPSTART: (list of supported <mode>),(<domain name>),(<port>)
OK
2) If AT+CIPMUX=1
+CIPSTART: (list of supported <n>),(list of supported <mode>),(<IP
address>),(<port>)
+CIPSTART: (list of supported <n>),(list of supported <mode>),(<domain
name>),(<port>)

OK
Parameters
See Write Command
Response
1)If single IP connection (+CIPMUX=0)
If format is right response
OK
otherwise response
+CME ERROR <err>
Response when connection exists
ALREADY CONNECT
Response when connection is successful
CONNECT OK
Otherwise
STATE: <state>
CONNECT FAIL
2)If multi-IP connection
(+CIPMUX=1)
If format is right
OK,
otherwise response
+CME ERROR <err>
Response when connection exists
<n>,ALREADY CONNECT
If connection is successful
<n>,CONNECT OK
Otherwise
<n>,CONNECT FAIL
Write Command
1)If single IP
connection
(+CIPMUX=0)
AT+CIPSTART=
<mode>,<IP
address>,<port>
Or
AT+CIPSTART=
<mode>,<domai
n name>,<port>
2)If multi-IP
connection
(+CIPMUX=1)
AT+CIPSTART=
<n>,<mode>,<ad
dress>,<port>
AT+CIPSTART=
<n>,<mode>,<do
main name>,
<port>
Parameters
<n> 0..7 a numeric parameter which indicates the connection
number
<mode> a string parameter(string should be included in quotation
marks) which indicates the connection type
"TCP" Establish a TCP connection
"UDP" Establish a UDP connection
<IP address> a string parameter(string should be included in quotation
marks) which indicates remote server IP address
<port> remote server port

<domain name> a string parameter(string should be included in quotation
marks) which indicates remote server domain name
<state> a string parameter(string should be included in quotation
marks) which indicates the progress of connecting
0 IP INITIAL
1 IP START
2 IP CONFIG
3 IP GPRSACT
4 IP STATUS
5 TCP CONNECTING/UDP CONNECTING/
SERVER LISTENING
6 CONNECT OK
7 TCP CLOSING/UDP CLOSING
8 TCP CLOSED/UDP CLOSED
9 PDP DEACT
In Multi-IP state:
0 IP INITIAL
1 IP START
2 IP CONFIG
3 IP GPRSACT
4 IP STATUS
5 IP PROCESSING
9 PDP DEACT
Reference Note
This command allows establishment of a TCP/UDP connection only
when the state is IP INITIAL or IP STATUS when it is in single state.
In multi-IP state, the state is in IP STATUS only. So it is necessary to
process "AT+CIPSHUT" before user establishes a TCP/UDP
connection with this command when the state is not IP INITIAL or IP
STATUS.
When module is in multi-IP state, before this command is executed, it
is necessary to process "AT+CSTT, AT+CIICR, AT+CIFSR".
8.2.3 AT+CIPSEND Send Data Through TCP or UDP Connection
AT+CIPSEND Send Data Through TCP or UDP Connection
Test Command
AT+CIPSEND=?
Response
1) For single IP connection (+CIPMUX=0)
+CIPSEND: <length>
OK
2) For multi IP connection (+CIPMUX=1)
+CIPSEND: <0-7>,<length>

OK
Parameters
See Write Command
Response
+CIPSEND:<size>
OK
+CIPSEND:<n><size>
OK
Read Command
AT+CIPSEND?
Parameters
<n> a numeric parameter which indicates the connection number
<size> a numeric parameter which indicates the data length sent at a
time
Write Command
1) If single IP
connection
(+CIPMUX=0)
AT+CIPSEND=<
length>
2) If multi IP
connection
(+CIPMUX=1)
AT+CIPSEND=<
n>[,<length>]
Response
This Command is used to send changeable length data
If single IP is connected (+CIPMUX=0)
If connection is not established or module is disconnected:
+CME ERROR <err>
If sending is successful:
When +CIPQSEND=0
SEND OK
When +CIPQSEND=1
DATA ACCEPT:<length>
If sending fails:
SEND FAIL
If multi IP connection is established (+CIPMUX=1)
+CME ERROR <err>
When +CIPQSEND=0
<n>,SEND OK
When +CIPQSEND=1
DATA ACCEPT:<n>,<length>
If sending fails:
<n>,SEND FAIL

Parameters
<length> a numeric parameter which indicates the length of sending
data, it must be less than <size>
Execution
Command
AT+CIPSEND
response">", then
type data for send,
tap CTRL+Z to
send, tap ESC to
cancel the
operation
Response
This Command is used to send changeable length data.
If single IP connection is established (+CIPMUX=0)
+CME ERROR <err>
When +CIPQSEND=0
SEND OK
When +CIPQSEND=1
DATA ACCEPT:<length>
If sending fails:
SEND FAIL
Note
This Command can only be used in single IP connection mode
(+CIPMUX=0) and to send data on the TCP or UDP connection that has
been established already. Ctrl-Z is used as a termination symbol. ESC is
used to cancel sending data. There are at most <size> bytes which can be
sent at a time.
Reference Note
The data length which can be sent depends on network status.
Set the time that send data automatically with the Command of
AT+CIPATS.
Only send data at the status of established connection.
8.2.4 AT+CIPQSEND Select Data Transmitting Mode
AT+CIPQSEND Select Data Transmitting Mode
Response
+CIPQSEND: (0,1)
OK
Test Command
AT+CIPQSEND
=?
Parameter
See Write Command

Response
+CIPQSEND: <n>
OK
Read Command
AT+CIPQSEND
?
Parameter
See Write Command
Response
OK
Write Command
AT+CIPQSEND
=<n>
Parameter
<n> 0 Normal mode – when the server receives TCP data, it will
responsd SEND OK.
1 Quick send mode – when the data is sent to module, it will
responsd DATA ACCEPT:<n>,<length>, while not responding
SEND OK.
Reference Note
8.2.5 AT+CIPACK Query Previous Connection Data Transmitting State
AT+CIPACK Query Previous Connection Data Transmitting State
Test Command
AT+CIPACK=?
Response
OK
Response
+CIPACK: <txlen>, <acklen>, <nacklen>
OK
Write Command
If in multi IP
connection
(+CIPMUX=1)
AT+CIPACK=<
n> Parameters
<txlen> the data amount which has been sent
<acklen> the data amount confirmed successfully by the server
<nacklen> the data amount without confirmation by the server
Response
+CIPACK: <txlen>, <acklen>, <nacklen>
OK
Execution
Command
If in single IP
connection
(+CIPMUX=0)
AT+CIPACK
Parameters
See Write Command
Reference Note

8.2.6 AT+CIPCLOSE Close TCP or UDP Connection
AT+CIPCLOSE Close TCP or UDP Connection
Test Command
AT+CIPCLOSE
=?
Response
OK
Response:
CLOSE OK
<n>, CLOSE OK
Write Command
1) If single IP
connection
(+CIPMUX=0)
AT+CIPCLOSE
=<n>
2) If multi IP
connection
(+CIPMUX=1)
AT+CIPCLOSE
=<id>, [<n>]
Parameters
<n> 0 slow close
1 quick close
<id> a numeric parameter which indicates the connection number
Execution
Command
AT+CIPCLOSE
Response
If close is successfully:
CLOSE OK
If close fails:
ERROR
Reference Note
AT+CIPCLOSE only closes connection at the status of TCP/UDP which
returns CONNECTING or CONNECT OK, otherwise it will return
ERROR, after the connection is closed, the status is IP CLOSE in single IP
mode
8.2.7 AT+CIPSHUT Deactivate GPRS PDP Context
AT+CIPSHUT Deactivate GPRS PDP Context
Test Command
AT+CIPSHUT=?
Response
OK
Execution
Command
AT+CIPSHUT
Response
If close is successful:
SHUT OK
If close fails:
ERROR
Reference Note
If this command is executed in multi-connection mode, all of the IP

connection will be shut.
User can close gprs pdp context by AT+CIPSHUT. After it is closed,
the status is IP INITIAL.
If "+PDP: DEACT" urc is reported which means the gprs is released by
the network, then user still needs to execute "AT+CIPSHUT"
command to make PDP context come back to original state.
8.2.8 AT+CLPORT Set Local Port
AT+CLPORT Set Local Port
Response
+CLPORT: (list of supported <port>s)
OK
Test Command
AT+CLPORT=?
Parameters
See Write Command
Response
TCP: <port>
UDP: <port>
OK
Read Command
AT+CLPORT?
Parameters
See Write Command
Response
OK
ERROR
Write Command
AT+CLPORT=<
mode>,<port>
Parameters
<mode> a string parameter(string should be included in quotation
marks) which indicates the connection type
"TCP" TCP local port
"UDP" UDP local port
<port> 0-65535 a numeric parameter which indicates the local port
0 is default value, a port can be dynamically allocated a port.
Reference Note
This command will be effective only in single connection mode
(+CIPMUX=0) and when module is set as a Client
8.2.9 AT+CSTT Start Task and Set APN, USER NAME, PASSWORD
AT+CSTT Start Task and Set APN, USER NAME, PASSWORD

+CSTT: "APN","USER","PWD"
OK
AT+CSTT=?
Parameters
See Write Command
Response
+CSTT: <apn>,<user name>,<password>
OK
Read Command
AT+CSTT?
Parameters
See Write Command
Response
OK
ERROR
Write Command
AT+CSTT=<apn
>,<user
name>,<passwor
d> Parameters
<apn> a string parameter (string should be included in quotation
marks) which indicates the GPRS access point name
<user name> a string parameter (string should be included in quotation
marks) which indicates the GPRS user name
<password> a string parameter (string should be included in quotation
marks) which indicates the GPRS password
Execution
Command
AT+CSTT
Response
OK
ERROR
Reference Note
The write command and execution command of this command is valid only
at the state of IP INITIAL. After this command is executed, the state will be
changed to IP START.
8.2.10 AT+CIICR Bring Up Wireless Connection with GPRS or CSD
AT+CIICR Bring Up Wireless Connection with GPRS or CSD
Test Command
AT+CIICR=?
Response
OK
Execution
Command
AT+CIICR
Response
OK
ERROR
Reference Note
AT+CIICR only activates moving scene at the status of IP START,

after operating this Command is executed, the state will be changed to
IP CONFIG.
After module accepts the activated operation, if it is activated
successfully, module state will be changed to IP GPRSACT, and it
responds OK, otherwise it will responsd ERROR.
8.2.11 AT+CIFSR Get Local IPAddress
AT+CIFSR Get Local IPAddress
Test Command
AT+CIFSR=?
Response
OK
Response
<IP address>
ERROR
Execution
Command
AT+CIFSR
Parameter
<IP address> a string parameter(string should be included in quotation
marks) which indicates the IP address assigned from GPRS
or CSD
Reference Note
Only after PDP context is activated, local IP Address can be obtained by
AT+CIFSR, otherwise it will respond ERROR. The active status are IP
GPRSACT, TCP/UDP CONNECTING, CONNECT OK, IP CLOSE.
8.2.12 AT+CIPSTATUS Query Current Connection Status
AT+CIPSTATUS Query Current Connection Status
Test Command
AT+CIPSTATUS
=?
Response
OK
Response
+CIPSTATUS: <n>,<bearer>, <TCP/UDP>, <IP address>, <port>,
<client state>
OK
Write Command
If multi IP
connection mode
(+CIPMUX=1)
AT+CIPSTATU
S=<n>
Parameters
Execution
Command
AT+CIPSTATUS
Response
1）If in single connection mode (+CIPMUX=0)
OK

STATE: <state>
2) If in multi-connection mode (+CIPMUX=1)
OK
STATE: <state>
If the module is set as server
S: 0, <bearer>, <port>, <server state>
C: <n>,<bearer>, <TCP/UDP>, <IP address>, <port>, <client state>
Parameters
<n> 0-7 a numeric parameter which indicates the connection
number
<bearer> 0-1 GPRS bearer, default is 0
<server state> OPENING
LISTENING
CLOSING
<client state> INITIAL
CONNECTING
CONNECTED
REMOTE CLOSING
CLOSING
CLOSED
<state> a string parameter(string should be included in quotation
marks) which indicates the progress of connecting
0 IP INITIAL
1 IP START
2 IP CONFIG
3 IP GPRSACT
4 IP STATUS
5 TCP CONNECTING/UDP CONNECTING
/SERVER LISTENING
6 CONNECT OK
7 TCP CLOSING/UDP CLOSING
8 TCP CLOSED/UDP CLOSED
9 PDP DEACT
In Multi-IP state:
0 IP INITIAL
1 IP START
2 IP CONFIG
3 IP GPRSACT
4 IP STATUS
5 IP PROCESSING
9 PDP DEACT

Reference Note
8.2.13 AT+CDNSCFG Configure Domain Name Server
AT+CDNSCFG Configure Domain Name Server
Response
+CDNSCFG: ("Primary DNS"),("Secondary DNS")
OK
Test Command
AT+CDNSCFG=
?
Parameter
See Write Command
Response
PrimaryDns: <pri_dns>
SecondaryDns: <sec_dns>
OK
Read Command
AT+CDNSCFG?
Parameter
See Write Command
Response
OK
ERROR
Write Command
AT+CDNSCFG=
<pri_dns>,[<sec_
dns>]
Parameters
<pri_dns> a string parameter(string should be included in quotation
marks) which indicates the IP address of the primary
domain name server
<sec_dns> a string parameter (string should be included in quotation
marks) which indicates the IP address of the secondary
domain name server
Reference Note
8.2.14 AT+CDNSGIP Query the IPAddress of Given Domain Name
AT+CDNSGIP Query the IPAddress of Given Domain Name
Test Command
AT+CDNSGIP=
?
Response
OK
Write Command
AT+CDNSGIP=
<domain name>
Response
OK
ERROR

If successful, return:
+CDNSGIP: 1, <domain name>,<IP>
If fail, return:
+CDNSGIP:0,<dns error code>
Parameters
<domain name> a string parameter(string should be included in
quotation marks) which indicates the domain name
<IP> a string parameter(string should be included in quotation
marks) which indicates the IP address corresponding to the
domain name
<dns error code> a numeric parameter which indicates the error code
10 DNS GENERAL ERROR
11 DNS MAX RETRIES,
12 DNS NO SERVER ADDR,
13 DNS NO MEMORY,
14 DNS INVALID NAME,
15 DNS INVALID RESP,
There are some other error code as well.
Reference Note
8.2.15 AT+CIPHEAD Add an IP Head at the Beginning of a Package Received
AT+CIPHEAD Add an IP Head at the Beginning of a Package Received
Response
+CIPHEAD: (list of supported <mode>s)
OK
Test Command
AT+CIPHEAD=
?
Parameter
See Write Command
Response
+CIPHEAD: <mode>
OK
Read Command
AT+CIPHEAD?
Parameter
See Write Command
Write Command
AT+CIPHEAD=
<mode>
Response
OK
ERROR

Parameter
<mode> a numeric parameter which indicates whether an IP header
is added to the received data or not.
0 not add IP header
1 add IP header, the format is "+IPD,data length:"
Reference Note
(+CIPMUX=0) and command mode.
8.2.16 AT+CIPATS Set Auto Sending Timer
AT+CIPATS Set Auto Sending Timer
Response
+CIPATS: (list of supported <mode>s),(list of supported <time>)
OK
Test Command
AT+CIPATS=?
Parameters
See Write Command
Response
+CIPATS: <mode>,<time>
OK
Read Command
AT+CIPATS?
Parameters
See Write Command
Response
OK
ERROR
Write Command
AT+CIPATS=<m
ode>[,<time>]
Parameters
<mode> a numeric parameter which indicates whether set timer when
module is sending data
0 not set timer when module is sending data
1 Set timer when module is sending data
<time> 1..100 a numeric parameter which indicates the seconds
after which the data will be sent
Reference Note
8.2.17 AT+CIPSPRT Set Prompt of ‘>’ When Module Sends Data
AT+CIPSPRT Set Prompt of ‘>’ When Module Sends Data

Response
+CIPSPRT: (list of supported <send prompt>s)
OK
Test Command
AT+CIPSPRT=?
Parameter
See Write Command
Response
+CIPSPRT: <send prompt>
OK
Read Command
AT+CIPSPRT?
Parameter
See Write Command
Response
OK
ERROR
Write Command
AT+CIPSPRT=<
send prompt>
Parameter
<send prompt> a numeric parameter which indicates whether to echo
prompt ‘>’ after module issues AT+CIPSEND command
0 it shows "send ok" but does not prompt echo ‘>’ when sending is
successful
1 it prompts echo ‘>’ and shows "send ok" when sending is
successful
2 it neither prompts echo ‘>’ nor shows "send ok" when sending is
successful
Reference Note
8.2.18 AT+CIPSERVER Configure Module as Server
AT+CIPSERVER Configure Module as Server
Response
+CIPSERVER: (0-CLOSE SERVER, 1-OPEN SERVER),(1,65535)
OK
Test Command
AT+CIPSERVE
R=?
Parameters
See Write Command
Read Command
AT+CIPSERVE
R?
Response
+CIPSERVER: <mode>[,<port>,<channel id>,<bearer>]
OK

Parameters
See Write Command
Response
OK
ERROR
Write Command
AT+CIPSERVE
R=<mode>[,<por
t>]
Parameters
<mode> 0 close server
1 open server
<port> 1..65535 Listening port
<channel id> channel id
<bearer> GPRS bearer
Reference Note
This command is allowed to establish a TCP server only when the state is IP
INITIAL or IP STATUS when it is in single state. In multi-IP state, the
state is in IP STATUS only.
8.2.19 AT+CIPCSGP Set CSD or GPRS for Connection Mode
AT+CIPCSGP Set CSD or GPRS for Connection Mode
Response
+CIPCSGP:0-CSD,DIALNUMBER,USER
NAME,PASSWORD,RATE(0-3)
+CIPCSGP: 1-GPRS,APN,USER NAME,PASSWORD
OK
Test Command
AT+CIPCSGP=?
Parameters
See Write Command
Response
+CIPCSGP: <mode>, <apn>, <user name>, <password>[,<rate>]
OK
Read Command
AT+CIPCSGP?
Parameters
See Write Command
Response
OK
ERROR
Write Command
AT+CIPCSGP=
<mode>,[(<apn>,
<user name>,
<password>),(<d Parameters

ial number>,
<user name>,
<password>,
<rate>)]
<mode> a numeric parameter which indicates the wireless connection
mode
0 set CSD as wireless connection mode
1 set GPRS as wireless connection mode
GPRS parameters:
<apn> a string parameter(string should be included in quotation
marks) which indicates the access point name
<user name> a string parameter(string should be included in quotation
marks) which indicates the user name
<password> a string parameter(string should be included in quotation
marks) which indicates the password CSD parameters:
<dial number> a string parameter(string should be included in quotation
marks) which indicates the CSD dial numbers
<user name> a string parameter(string should be included in quotation
marks) which indicates the CSD user name
<password> a string parameter(string should be included in quotation
marks) which indicates the CSD password
<rate> a numeric parameter which indicates the CSD connection
rate
0 2400
1 4800
2 9600
3 14400
Reference Note
8.2.20 AT+CIPSRIP Show Remote IP Address and Port When Received Data
AT+CIPSRIP Show Remote IP Address and Port When Received Data
Response
+CIPSRIP: (list of supported <mode>s)
OK
Test Command
AT+CIPSRIP=?
Parameter
See Write Command
Response
+CIPSRIP: <mode>
OK
Read Command
AT+CIPSRIP?
Parameter

See Write Command
Response
OK
ERROR
Write Command
AT+CIPSRIP=<
mode>
Parameter
<mode> a numeric parameter which shows remote IP address and
port.
0 do not show the prompt
1 show the prompt, the format is as follows: RECV
FROM:<IP ADDRESS>:<PORT>
Reference Note
(+CIPMUX=0)
8.2.21 AT+CIPDPDP Set Whether to Check State of GPRS Network Timing
AT+CIPDPDP Set Whether to Check State of GPRS Network Timing
Response
+CIPDPDP: (list of supported<mode>s, list of supported <interval>, list
of supported <timer> )
OK
Test Command
AT+CIPDPDP
=?
Parameters
See Write Command
Response
+CIPDPDP: <mode>, <interval>, <timer>
OK
Read Command
AT+CIPDPDP?
Parameters
See Write Command
Response
OK
ERROR
Write Command
AT+CIPDPDP=<
mode>[,<interval
>,<timer>]
Parameters
<mode>
0 not set detect PDP
1 set detect PDP
<interval>

1<interval<=180(s)
<timer>
1<timer<=10
Reference Note
If "+PDP: DEACT" urc is reported because of module not attaching to gprs
for a certain time or other reasons, user still needs to execute
"AT+CIPSHUT" command makes PDP context come back to original state.
8.2.22 AT+CIPMODE Select TCPIPApplication Mode
AT+CIPMODE Select TCPIPApplication Mode
Response
+CIPMODE: (0-NORMAL MODE,1-TRANSPARENT MODE)
OK
Test Command
AT+CIPMODE=
?
Parameter
See Write Command
Response
+CIPMODE: <mode>
OK
Read Command
AT+CIPMODE?
Parameter
See Write Command
Response
OK
ERROR
Write Command
AT+CIPMODE=
<mode>
Parameter
<mode> 0 normal mode
1 transparent mode
Reference Note
8.2.23AT+CIPCCFG Configure Transparent Transfer Mode
AT+CIPCCFG Configure Transparent Transfer Mode
Response
+CIPCCFG: (NmRetry:3-8),(WaitTm:2-10),(SendSz:1-1460),(esc:0,1)
OK
Test Command
AT+CIPCCFG=
?
Parameters

See Write Command
Response
+CIPCCFG: <NmRetry>,<WaitTm>,<SendSz>,<esc>
OK
Read Command
AT+CIPCCFG?
Parameters
See Write Command
Response
OK
ERROR
Write Command
AT+CIPCCFG=
<NmRetry>,<Wa
itTm>,<SendSz>,
<esc> Parameters
<NmRetry> number of retries to be made for an IP packet.
<WaitTm> number of 200ms intervals to wait for serial input before
sending the packet.
<SendSz> size in bytes of data block to be received from serial port
before sending.
<esc> whether turn on the escape sequence is turned on, default
is TRUE.
Reference Note
(+CIPMUX=0)
8.2.24 AT+CIPSHOWTP Display Transfer Protocol in IP Head When Received Data
AT+CIPSHOWTP Display Transfer Protocol in IP Head When Received Data
Response
+CIPSHOWTP: (list of supported <mode>s)
OK
Test Command
AT+CIPSHOWTP
=?
Parameter
See Write Command
Response
+CIPSHOWTP: <mode>
OK
Read Command
AT+CIPSHOWTP
?
Parameter
See Write Command
Write Command
AT+CIPSHOWTP
Response
OK

=<mode> ERROR
Parameter
<mode> a numeric parameter which indicates whether to display
transfer protocol in IP header to received data or not
0 not display transfer protocol
1 display transfer protocol, the format is "+IPD,
<data size>,<TCP/UDP>:<data>"
Reference Note
(+CIPMUX=0)
Only when +CIPHEAD is set to 1, the setting of this command will
work
8.2.25 AT+CIPUDPMODE UDP Extended Mode
AT+CIPUDPMODE UDP Extended Mode
Response
+ CIPUDPMODE: (0-2),("(0,255).(0,255).(0,255).(0,255)"),(1,65535)
OK
Test Command
AT+CIPUDPMOD
E=?
Parameters
See Write Command
Response
+CIPUDPMODE: <mode>,[<IP address>,<Port>]
OK
Read Command
AT+CIPUDPMOD
E?
Parameter
See Write Command
Response
OK
ERROR
Write Command
AT+CIPUDPMOD
E=<mode>,[<IP
address>,<Port>]
Parameter
<mode> 0 UDP Normal Mode
1 UDP Extended Mode
2 Set UDP address to be sent
<IP address> a string parameter (string should be included in quotation
marks) which indicates remote IP address
<port> remote port

Reference Note
This Command is used to set UDP extended mode, for single IP connection
(+CIPMUX=0)
8.2.26 AT+CIPRXGET Get Data from Network Manually
AT+CIPRXGET Get Data from Network Manually
Response
+CIPRXGET: (list of supported <mode>s),(list of supported <len>)
OK
Test Command
AT+CIPRXGET
=?
Parameters
See Write Command
Response
+CIPRXGET: <mode>
OK
Read Command
AT+CIPRXGET
?
Parameters
See Write Command
Response
OK
ERROR
Write Command
1) If single IP
connection
(+CIPMUX=0)
AT+CIPRXGET
=<mode>[,<len>]
2) If multi IP
connection
(+CIPMUX=1)
AT+CIPRXGET
=<mode>,<id>[,<
len>]
Parameters
<mode>
0 disable getting data from network manually, the module is
set to normal mode, data will be pushed to TE directly.
1 enable getting data from network manually.
2 the module can get data, but the length of output data can
not exceed 1460 bytes at a time.
3 similar to mode 2, but in HEX mode, which means the
module can get 730 bytes maximum at a time.
4 query how many data are not read with a given ID.
<id> a numeric parameter which indicates the connection number
<len> 1-1460 (bytes) the supported length of data.
Reference Note
To enable this function, parameter <mode> must be set to 1 before
connection.

8.2.27 AT+CIPQRCLOSE Quick Remote Close
AT+CIPQRCLOSE Quick Remote Close
Response
+CIPQRCLOSE: (list of supported <mode>s)
OK
Test Command
AT+CIPQRCLO
SE=?
Parameter
See Write Command
Response
+CIPQRCLOSE: <mode>
OK
Read Command
AT+CIPQRCLO
SE?
Parameter
See Write Command
Response
OK
ERROR
Write Command
AT+CIPQRCLO
SE=<mode>
Parameter
<mode> 0 module returns FIN frame after module received FIN
frame from remote side
1 module returns RST frame after module received FIN
frame from remote side
Reference Note
If RST frame instead of FIN frame is responded to remote side,
disconnection process will speed up.
To enable this function, parameter <mode> must be set to 1 before
connection.
8.2.28 AT+CIPSCONT Save TCPIPApplication Context
AT+CIPSCONT Save TCPIPApplication Context
Read Command
AT+CIPSCONT
?
Response
TA returns TCPIP Application Context, which consists of the following
AT Command parameters.
+CIPSCONT:<mode0>
+CIPCSGP:<mode>
Gprs Config APN:<apn>
Gprs Config UserId:<user name>

Gprs Config Password:<password>
+CLPORT:<port>
+CIPHEAD:<mode>
+CIPSHOWTP:<mode>
+CIPSRIP:<mode>
+CIPATS:<mode>,<time>
+CIPSPRT:<send prompt>
+CIPQSEND:<n>
+CIPMODE:<mode>
+CIPCCFG:<NmRetry>,<WaitTm>,<SendSz>,<esc>
+CIPMUX:<n>
+CIPDPDP:<mode>, <interval>, <timer>
+CIPRXGET:<mode>
+CIPQRCLOSE:<mode>
+CIPUDPMODE:<mode>
OK
Parameters
<mode0> 0 saved, the value from NVRAM
1 unsaved, the value from RAM
For other parameters, see the related command.
Execution
Command
AT+CIPSCONT
Response
Module saves current TCPIP Application Contexts to NVRAM. When
system is rebooted, the parameters will be loaded automatically.
OK
Reference Note

9 AT Commands for IP Application
9.1 Overview
Command Description
AT+SAPBR BEARER SETTINGS FOR APPLICATIONS BASED ON IP
9.2.1 AT+SAPBR Bearer Settings for Applications Based on IP
AT+SAPBR Bearer Settings for Applications Based on IP
Response
+SAPBR: (0-5),(1-3), "ConParamTag","ConParamValue"
OK
Test Command
AT+SAPBR=?
Parameters
See Write Command
Response
OK
If<cmd_type> = 2
+SAPBR: <cid>,<Status>,<IP_Addr>
OK
If <cmd_type>=4
+SAPBR:
<ConParamTag>,<ConParamValue>
OK
+SAPBR <cid>: DEACT
Write Command
AT+SAPBR
=<cmd_type>,<ci
d>,[<ConParam
Tag>,<ConPara
mValue>]
Parameters
<cmd_type>
0 close bearer
1 open bearer
2 query bearer
3 set bearer parameters
4 get bearer parameters
5 save the values of parameters to NVRAM
SIM300_ATC_V1.03 1 08.29.2008

<cid> bearer profile identifier
<Status>
0 bearer is connecting
1 bearer is connected
2 bearer is closing
3 bearer is closed
<ConParamTag> bearer parameter
"CONTYPE" Type of Internet connection. Value refer to
<ConP"aramValue_ConType>
"APN" Access point name string: maximum 50
characters
"USER" User name string: maximum 50 characters
"PWD" Password string: maximum 50 characters
"PHONENUM" Phone number for CSD call
"RATE" CSD connection rate. For value refer to
<ConParamValue_Rate>
<ConParamValue> bearer paramer value
<ConParamValue_ConType>
"CSD" Circuit-switched data call.
"GPRS" GPRS connection.
<ConParamValue_Rate>
0 2400
1 4800
2 9600
3 14400
<IP_Addr> the IP address of bearer
Reference Note
This command is applied to activate some applications such as HTTP, FTP.

10 AT Commands for HTTP Application
SIM900 has an embedded TCP/IP stack that is driven by AT commands and enables the host
application to easily access the Internet HTTP service. This chapter is a reference guide to all the
AT commands and responses defined to use with the TCP/IP stack in HTTP Service.
10.1 Overview
Command Description
AT+HTTPINIT INITIALIZE HTTP SERVICE
AT+HTTPTERM TERMINATE HTTP SERVICE
AT+HTTPPARA SET HTTP PARAMETERS VALUE
AT+HTTPDATA INPUT HTTP DATA
AT+HTTPACTIO
N
HTTP METHOD ACTION
AT+HTTPREAD READ THE HTTP SERVER RESPONSE
AT+HTTPSCON
T
SAVE HTTP APPLICATION CONTEXT
10.2.1 AT+HTTPINIT Initialize HTTP Service
AT+HTTPINIT Initialize HTTP Service
Test Command
AT+HTTPINIT=
?
Response
OK
Execution
Command
AT+HTTPINIT
Response
OK
+CME ERROR: <err>
Reference Note
HTTPINIT should first be executed to initialize the HTTP service.
10.2.2 AT+HTTPTERM Terminate HTTP Service
AT+HTTPTERM Terminate HTTP Service

Test Command
AT+HTTPTER
M=?
Response
OK
Execution
command
AT+
HTTPTERM
Response
OK
+CME ERROR: <err>
Reference Note
10.2.3 AT+HTTPPARA Set HTTP Parameters Value
AT+HTTPPARA Set HTTP Parameters Value
Response
+HTTPPARA: "HTTPParamTag","HTTPParmValue"
OK
Test Command
AT+HTTPPARA
=?
Parameters
See Write Command
Response
+ HTTPPARA:
<HTTPParamTag>,<HTTPParamValue>
OK
Read Command
AT+HTTPPARA
?
Parameters
See Write Command
Response
OK
+CME ERROR: <err>
Write Command
AT+
HTTPPARA
=<HTTPParamT
ag>,<HTTPPara
mValue> Parameters
<HTTPParamTag> HTTP Parameter
"CID" (Mandatory Parameter) bearer profile identifier
"URL" (Mandatory Parameter) HTTP client URL
"http://'server'/'path':'tcpPort' "
"server": FQDN or IP-address
"path": path of file or directory
"tcpPort": default value is 80. Refer to
"IETF-RFC 2616".

"UA" The user agent string which is set by the
application to identify the mobile. Usually this
parameter is set as operation system and software
version information.
Default value is SIMCOM_MODULE.
"PROIP" The IP address of HTTP proxy server
"PROPORT" The port of HTTP proxy server
"REDIR" This flag controls the redirection mechanism of
the SIM900 when it is acting as HTTP client
(numeric). If the server sends a redirect code
(range 30x), the client will automatically send a
new HTTP request when the flag is set to (1).
Default value is 0 (no redirection).
"BREAK" Parameter for HTTP method "GET" used for
resuming broken transfer.
"BREAKEND" Parameter for HTTP method "GET", used for
resuming broken transfer. which is used together
with "BREAK",
If the value of "BREAKEND" is bigger than
"BREAK", the transfer scope is from "BREAK"
to "BREAKEND".
If the value of "BREAKEND" is smaller than
"BREAK", the transfer scope is from "BREAK"
to the end of the file.
If both "BREAKEND" and "BREAK" are 0, the
resume broken transfer function is disabled.
<HTTPParamValue> HTTP Parameter value.
Type and supported content depend on related
<HTTPParamTag>.
Reference Note
Not all the HTTP Server supports "BREAK" and "BREAKEND"
parameters
10.2.4 AT+HTTPDATA Input HTTP Data
AT+HTTPDATA Input HTTP Data
Response
+HTTPDATA: (1-318976),(1000-120000)
OK
Test Command
AT+HTTPDATA
=?
Parameters
See Write Command

Response
DOWNLOAD
OK
+CME ERROR: <err>
Write Command
AT+HTTPDATA
=<size>,<time>
Parameters
<size> Size in bytes of the data to POST.
<time> Maximum time in milliseconds to input data.
Reference Note
It is strongly recommended to set enough time to input all datawith the
length of <size>.
10.2.5 AT+HTTPACTION HTTP Method Action
AT+HTTPACTION HTTP Method Action
Response
+HTTPACTION: (0-2)
OK
Test Command
AT+HTTPACTI
ON=?
Parameter
See Write Command
Response
OK
+CME ERROR: <err>
+HTTPACTION: <Method>,<StatusCode>,<DataLen>
Write Command
AT+HTTPACTI
ON=<Method>
Parameter
<Method> HTTP method specification:
0 GET
1 POST
2 HEAD
<StatusCode> HTTP Status Code responded by remote server, it
identifier refer to HTTP1.1(RFC2616)
100 Continue

101 Switching Protocols
200 OK
201 Created
202 Accepted
203 Non-Authoritative Information
204 No Content
205 Reset Content
206 Partial Content
300 Multiple Choices
301 Moved Permanently
302 Found
303 See Other
304 Not Modified
305 Use Proxy
307 Temporary Redirect
400 Bad Request
401 Unauthorized
402 Payment Required
403 Forbidden
404 Not Found
405 Method Not Allowed
406 Not Acceptable
407 Proxy Authentication Required
408 Request Time-out
409 Conflict
410 Gone
411 Length Required
412 Precondition Failed
413 Request Entity Too Large
414 Request-URI Too Large
415 Unsupported Media Type
416 Requested range not satisfiable
417 Expectation Failed
500 Internal Server Error
501 Not Implemented
502 Bad Gateway
503 Service Unavailable
504 Gateway Time-out
505 HTTP Version not supported
600 Not HTTP PDU
601 Network Error
602 No memory
603 DNS Error
604 Stack Busy

<DataLen> the length of data got
Reference Note
10.2.6 AT+HTTPREAD Read the HTTP Server Response
AT+HTTPREAD Read the HTTP Server Response
Response
+HTTPREAD: (1- 318976),(1- 318976)
OK
Test Command
AT+HTTPREA
D=?
Parameters
See Write Command
Response
+HTTPREAD: <date_len>
<data>
OK
Read data when AT+HTTPACTION=0 or AT+HTTPDATA is executed.
If<byte_size> is bigger than the data size received, module will only return
actual data size.
+CME ERROR: <err>
Write Command
AT+
HTTPREAD
=<start_address
><byte_size>
Parameters
<data> data from HTTP server or user input
<start_address> The starting point for data output
<byte_size> The length for data output
<data_len> The actual length for data output
Execution
Command
AT+HTTPREA
D
Response
+HTTPREAD:<date_len>
<data>
OK
Read all data when AT+HTTPACTION=0 or AT+HTTPDATA is executed.

+CME ERROR: <err>
Reference Note
10.2.7 AT+HTTPSCONT Save HTTPApplication Context
AT+HTTPSCONT Save HTTPApplication Context
Response
TA returns HTTP Application Context, which consists of the following
AT Command parameters.
+HTTPSCONT:<mode>
CID:<value>
URL: <value>
UA: <value>
PROIP: <value>
PROPORT: <value>
REDIR: <value>
BREAK: <value>
BREAKEND: <value>
OK
Read Command
AT+HTTPSCON
T?
Parameters
<mode> 0 saved, the value from NVRAM
Response
TA saves HTTP Application Context which consists of following AT
Command parameters, and when system is rebooted, the parameters will
be loaded automatically.
OK
+CME ERROR: <err>
Execution
Command
AT+HTTPSCON
T
Parameter
Reference Note

11 AT Commands for FTP Application
SIM900 has an embedded TCP/IP stack that is driven by AT commands and enables the host
application to easily access the Internet FTP service. This chapter is a reference guide to all the AT
commands and responses defined for using with the TCP/IP stack in FTP Service.
11.1 Overview
Command Description
AT+FTPPORT SET FTP CONTROL PORT
AT+FTPMODE SET ACTIVE OR PASSIVE FTP MODE
AT+FTPTYPE SET THE TYPE OF DATA TO BE TRANSFERRED
AT+FTPPUTOPT SET FTP PUT TYPE
AT+FTPCID SET FTP BEARER PROFILE IDENTIFIER
AT+FTPREST SET RESUME BROKEN DOWNLOAD
AT+FTPSERV SET FTP SERVER ADDRESS
AT+FTPUN SET FTP USER NAME
AT+FTPPW SET FTP PASSWORD
AT+FTPGETNA
ME
SET DOWNLOAD FILE NAME
AT+FTPGETPAT
H
SET DOWNLOAD FILE PATH
AT+FTPPUTNA
ME
SET UPLOAD FILE NAME
AT+FTPPUTPAT
H
SET UPLOAD FILE PATH
AT+FTPGET DOWNLOAD FILE
AT+FTPPUT SET UPLOAD FILE
AT+FTPSCONT SAVE FTP APPLICATION CONTEXT
11.2.1 AT+FTPPORT Set FTP Control Port
AT+FTPPORT Set FTP Control Port
Test Command
AT+FTPPORT
=?
Response
OK
SIM300_ATC_V1.03 1 08.29.2008

Response
+FTPPORT: <value>
OK
Read Command
AT+ FTPPORT?
Parameter
See Write Command
Response
OK
+CME ERROR: <err>
Write Command
AT+FTPPORT
=<value>
Parameter
<value> The value of FTP Control port, from 1 to 65535.
Default value is 21
Reference Note
Numbers above 65535 are illegal as the port identification fields are 16 bits
long in the TCP header.
11.2.2 AT+FTPMODE Set Active or Passive FTP Mode
AT+FTPMODE Set Active or Passive FTP Mode
Test Command
AT+FTPMODE
=?
Response
OK
Response
+FTPMODE: <value>
OK
Read Command
AT+FTPMODE?
Parameter
See Write Command
Response
OK
+CME ERROR: <err>
Write Command
AT+FTPMODE
=<value>
Parameter
<value> 0 Active FTP mode
1 Passive FTP mode
Reference Note

11.2.3 AT+FTPTYPE Set the Type of Data to Be Transferred
AT+FTPTYPE Set the Type of Data to Be Transferred
Test Command
AT+FTPTYPE
=?
Response
OK
Response
+FTPTYPE: <value>
OK
Read Command
AT+FTPTYPE?
Parameter
See Write Command
Response
OK
+CME ERROR: <err>
Write Command
AT+FTPTYPE
=<value>
Parameter
<value> "A" for FTP ASCII sessions
"I" for FTP Binary sessions
Reference Note
When this value is set to A, all the data sent by the stack to the FTP server is
made of 7 bits characters (NVT-ASCII: the MSB is set to 0). As a
consequence binary data containing 8 bits characters will be corrupted
during the transfer if the FTPTYPE is set to A.
11.2.4 AT+FTPPUTOPT Set FTP Put Type
AT+FTPPUTOPT Set FTP Put Type
Test Command
AT+FTPPUTOP
T =?
Response
OK
Response
+FTPPUTOPT: <value>
OK
Read Command
AT+FTPPUTOP
T?
Parameter
See Write Command
Write Command
AT+FTPPUTOP
T =<value>
Response
OK

+CME ERROR: <err>
Parameter
<value> "APPE" for appending file
"STOU" for storing unique file
"STOR" for storing file
Reference Note
11.2.5 AT+FTPCID Set FTP Bearer Profile Identifier
AT+FTPCID Set FTP Bearer Profile Identifier
Response
OK
Test Command
AT+FTPCID=?
Parameter
See Write Command
Response
+ FTPCID: <value>
OK
Read Command
AT+FTPCID?
Parameter
See Write Command
Response
OK
+CME ERROR: <err>
Write Command
AT+FTPCID=<v
alue>
Parameter
<value> bearer profile identifier refer to AT+SAPBR
Reference Note
11.2.6 AT+FTPREST Set Resume Broken Download
AT+FTPREST Set Resume Broken Download
Test Command
AT+FTPREST
=?
Response
OK

Response
+ FTPREST: <value>
OK
Read Command
AT+ FTPREST?
Parameter
See Write Command
Response
OK
+CME ERROR: <err>
Write Command
AT+FTPREST=
<value>
Parameter
<value> broken point to be resumed
Reference Note
11.2.7 AT+FTPSERV Set FTP Server Address
AT+FTPSERV Set FTP Server Address
Test Command
AT+FTPSERV
=?
Response
OK
Response
+FTPSERV: <value>
OK
Read Command
AT+FTPSERV?
Parameter
See Write Command
Response
OK
+CME ERROR: <err>
Write Command
AT+FTPSERV
=<value>
Parameter
<value> 32-bit number in dotted-decimal notation
(i.e. xxx.xxx.xxx.xxx) or alphanumeric ASCII text string up to
49 characters if DNS is available
Reference Note

11.2.8 AT+FTPUN Set FTP User Name
AT+FTPUN Set FTP User Name
Response
OK
Test Command
AT+FTPUN=?
Parameter
See Write Command
Response
+FTPUN: <value>
OK
Read Command
AT+FTPUN?
Parameter
See Write Command
Response
OK
+CME ERROR: <err>
Write Command
AT+FTPUN=<va
lue>
Parameter
<value> Alphanumeric ASCII text string up to 49 characters.
Reference Note
11.2.9 AT+FTPPW Set FTP Password
AT+FTPPW Set FTP Password
Response
OK
Test Command
AT+FTPPW =?
Parameter
See Write Command
Read Command
AT+FTPPW?
Response
+FTPPW: <value>
OK

Parameter
See Write Command
Response
OK
+CME ERROR: <err>
Write Command
AT+FTPPW
=<value>
Parameter
<value> Alphanumeric ASCII text string up to 49 characters.
Reference Note
11.2.10 AT+FTPGETNAME Set Download File Name
AT+FTPGETNAME Set Download File Name
Test Command
AT+FTPGETNA
ME =?
Response
OK
Response
+ FTPGETNAME: <value>
OK
Read Command
AT+FTPGETNA
ME?
Parameter
See Write Command
Response
OK
+CME ERROR: <err>
Write Command
AT+FTPGETNA
ME =<value>
Parameter
<value> Alphanumeric ASCII text string up to 99 characters
Reference Note
11.2.11 AT+FTPGETPATH Set Download File Path
AT+FTPGETPATH Set Download File Path
Test Command
AT+FTPGETPA
TH =?
Response
OK

Response
+FTPGETPATH: <value>
OK
Read Command
AT+FTPGETPA
TH?
Parameter
See Write Command
Response
OK
+CME ERROR: <err>
Write Command
AT+FTPGETPA
TH =<value>
Parameter
Reference Note
11.2.12 AT+FTPPUTNAME Set Upload File Name
AT+FTPPUTNAME Set Upload File Name
Test Command
AT+FTPPUTNA
ME=?
Response
OK
Response
+FTPPUTNAME: <value>
OK
Read Command
AT+FTPPUTNA
ME?
Parameter
See Write Command
Response
OK
+CME ERROR: <err>
Write Command
AT+FTPPUTNA
ME =<value>
Parameter
Reference Note

11.2.13 AT+FTPPUTPATH Set Upload File Path
AT+FTPPUTPATH Set Upload File Path
Test Command
AT+FTPPUTPA
TH =?
Response
OK
Response
+FTPPUTPATH: <value>
OK
Read Command
AT+FTPPUTPA
TH?
Parameter
See Write Command
Response
OK
+CME ERROR: <err>
Write Command
AT+FTPPUTPA
TH =<value>
Parameter
Reference Note
11.2.14 AT+FTPGET Download File
AT+FTPGET Download File
Test Command
AT+FTPGET =?
Response
OK
Write Command
AT+FTPGET
=<mode>,[<reqle
ngth>]
Response
If mode is 1 and it is a successful FTP get session:
OK
+FTPGET:1,1
If data transfer finished:
+FTPGET:1,0
If mode is 1 and it is a failed FTP get session:
OK
+FTPGET:1,<error>
If mode is 2:
+FTPGET:2,<cnflength>

012345678…
OK
+CME ERROR: <err>
Parameters
<mode> 1 for opening FTP get session
2 for reading FTP download data.
<reqlength> Requested number of data bytes (1-1460)to be read
<cnflength> Confirmed number of data bytes to be read, which may be less
than <length>. 0 indicates that no data can be read.
<error> 61 Net error
62 DNS error
63 connect error
64 timeout
65 server error
66 operation not allow
70 replay error
71 user error
72 password error
73 type error
74 rest error
75 passive error
76 active error
77 operate error
78 upload error
79 download error
Reference Note
When "+FTPGET:1,1" is shown,then use AT+FTPGET:2,<reqlength> to
read data. If the module still has unread data, "+FTPGET:1,1" will be
shown again in a certain time.
11.2.15 AT+FTPPUT Set Upload File
AT+FTPPUT Set Upload File
Test Command
AT+FTPPUT=?
Response
OK
Write Command
AT+FTPPUT
=<mode>,[<reqle
ngth>]
Response
If mode is 1 and it is a successful FTP get session:
OK
+FTPPUT:1,1,<maxlength>
If mode is 1 and it is a failed FTP get session:

OK
+FTPPUT:1,<error>
If mode is 2 and <reqlength> is not 0
+FTPPUT:2,<cnflength>
…… //Input data
OK
If mode is 2 and <reqlength> is 0, it will respond OK, and FTP session will
be closed
OK
If data transfer finished.
+FTPPUT:1,0
+CME ERROR: <err>
Parameters
<mode> 1 for opening FTP put session
2 for writing FTP upload data.
<reqlength> Requested number of data bytes(0-<maxlength>) to be
transmitted
<cnflength> Confirmed number of data bytes to be transmitted
<maxlength> The max. length of data can be sent at a time. It depends on
the network status.
<error> see AT+FTPGET
Reference Note
When "+FTPPUT:1,1,<maxlength>" is shown, then use AT+FTPPUT=2,
<reqlength> to write data.
11.2.16 AT+FTPSCONT Save FTPApplication Context
AT+FTPSCONT Save FTPApplication Context
Read Command
AT+FTPSCONT
?
Response
TA returns FTP Application Context, which consists of the following AT
Command parameters.
+FTPSCONT:<mode>
+FTPSERV: <value>
+FTPPORT: <value>
+FTPUN: <value>
+FTPPW: <value>
+FTPCID: <value>

+FTPMODE: <value>
+FTPTYPE: <value>
+FTPPUTOPT: <value>
+FTPREST: <value>
+FTPGETNAME: <value>
+FTPGETPATH: <value>
+FTPPUTNAME: <value>
+FTPPUTPATH: <value>
+FTPTIMEOUT: <value>
OK
Parameter
<mode> 0 saved, the value from NVRAM
Execution
Command
AT+FTPSCONT
Response
TA saves FTP Application Context which consist of following AT
Command parameters, and when system is rebooted, the parameters will
be loaded automatically.
OK
Reference Note

12 Supported Unsolicited Result Codes
12.1 Summary of CME ERROR Codes
Final result code +CME ERROR: <err> indicates an error related to mobile equipment or network.
The operation is similar to ERROR result code. None of the following commands in the same
Command line is executed. Neither ERROR nor OK result code shall be returned.
<err> values used by common messaging commands:
Code of <err> Meaning
0 phone failure
1 no connection to phone
2 phone-adaptor link reserved
3 operation not allowed
4 operation not supported
5 PH-SIM PIN required
6 PH-FSIM PIN required
7 PH-FSIM PUK required
10 SIM not inserted
11 SIM PIN required
12 SIM PUK required
13 SIM failure
14 SIM busy
15 SIM wrong
16 incorrect password
17 SIM PIN2 required
18 SIM PUK2 required
20 memory full
21 invalid index
22 not found
23 memory failure
24 text string too long
25 invalid characters in text string
26 dial string too long
27 invalid characters in dial string
30 no network service
31 network timeout
32 network not allowed - emergency calls only
SIM300_ATC_V1.03 1 08.29.2008

40 network personalization PIN required
41 network personalization PUK required
42 network subset personalization PIN required
43 network subset personalization PUK required
44 service provider personalization PIN required
45 service provider personalization PUK required
46 corporate personalization PIN required
47 corporate personalization PUK required
99 Resource limitation
100 Unknown
103 illegal MS
106 illegal ME
107 GPRS services not allowed
111 PLMN not allowed
112 location area not allowed
113 roaming not allowed in this location area
132 service option not supported
133 requested service option not subscribed
134 service option temporarily out of order
148 unspecified GPRS error
149 PDP authentication failure
150 invalid mobile class
12.2 Summary of CMS ERROR Codes
Final result code +CMS ERROR: <err> indicates an error related to message service or network.
The operation is similar to ERROR result code. None of the following commands in the same
Command line is executed. Neither ERROR nor OK result code shall be returned.
<err> values used by common messaging commands:
Code of <err> Meaning
300 ME failure
301 SMS ME reserved
302 Operation not allowed
303 Operation not supported
304 Invalid PDU mode
305 Invalid text mode

310 SIM not inserted
311 SIM pin necessary
312 PH SIM pin necessary
313 SIM failure
314 SIM busy
315 SIM wrong
316 SIM PUK required
317 SIM PIN2 required
318 SIM PUK2 required
320 Memory failure
321 Invalid memory index
322 Memory full
323 Invalid parameter
324 Invalid input format
330 SMSC address unknown
331 No network
332 Network timeout
340 No CNMA ack
500 Unknown
512 SIM not ready
513 Unread records on SIM
514 CB error unknown
515 PS busy
517 SM not ready
528 Invalid (non-hex) chars inPDU
529 Incorrect PDU length
530 Invalid MTI
531 Invalid (non-hex) chars in address
532 Invalid address (no digits read)
533 Incorrect PDU length (UDL)
534 Incorrect SCA length
536 Invalid First Octet (should be 2 or 34)
537 Invalid Command type
538 SRR bit not set
539 SRR bit set
540 Invalid User Data Header IE
753 CRSM missing parameter
754 CRSM invalid command

755 CRSM invalid file ID
756 CRSM missing P parameter
757 CRSM invalid P parameter
758 CRSM missing command data
759 CRSM invalid characters in command data.
765 Invalid input value
766 Unsupported mode
767 Operation failed
768 Mux already running
769 Unable to get control
770 SIM network reject
771 Call setup in progress
772 SIM powered down
773 SIM file not present

13 AT Commands Sample
13.1 Profile Commands
Demonstration Syntax Expect Result
The AT
Command
interpreter
actively
responds to
input.
AT OK
Display the
product name
and the product
release
information.
ATI SIM900 R11.0
Display
product
identification
information:
the
manufacturer,
the product
name and the
product
revision
information.
AT+GSV SIMCOM_Ltd
SIMCOM_SIM900
Revision:1137B01SIM900M32_ST
OK
Display current
configuration, a
list of the
current active
profile
parameters.
AT&V [A complete listing of the active profile]
OK
Reporting of
mobile
equipment
errors. The
default CME
error reporting
setting is
disabled.
Switch to
verbose mode
AT+CMEE=?
AT+CMEE?
AT+CSCS=?
AT+CSCS="TEST"
+CMEE: (0-2)
OK
+CMEE: 1
OK
+CSCS:
("IRA","GSM","UCS2","HEX","PCCP","PCDN","8859-1")
OK
SIM300_ATC_V1.03 1 08.29.2008

Displays a
string
explaining the
error in more
details.
AT+CMEE=2
AT+CSCS="TEST"
ERROR
OK
+CME ERROR: operation not allowed
Store the
current
configuration
in nonvolatile
memory. When
the board is
reset, the
configuration
changes from
the last session
are loaded.
ATE0&W
AT
[Reset the board]
AT
ATE1&W
AT
OK
[No echo]
OK
[No echo]
OK
[No echo]
OK
[Echo on]
OK
Set the ME to
minimum
functionality
AT+IPR？
AT+CFUN=0
AT+IPR = 115200
AT+IPR?
AT+CFUN=0
+IPR:0
OK
OK
+CPIN: NOT READY
OK
+IPR:115200
OK
+CPIN: NOT READY
ME has entered full functionality mode. AT+CFUN? +CFUN:1
OK
13.2 SIM Commands
List available
phonebooks, and
select the SIM
phonebook.
AT+CPBS=? +CPBS:
("MC","RC","DC","LD","LA","ME","SM","FD",
"ON","BN","SD","VM","EN")
OK

AT+CPBS="SM" OK
Display the ranges of
phonebook entries
and list the contents
of the phonebook.
AT+CPBR=?
AT+CPBR=1,10
+CPBR: (1-250),40,14
OK
[a listing of phonebook contents]
OK
Write an entry to the
current phonebook.
AT+CPBW=,"13918
18xxxx",129,"Daniel"
AT+CPBR=1,10
OK
OK
Find an entry in the
current phonebook
using a text search.
AT+CPBF="Daniel" +CPBF:5, "13918186089",129,"Daniel"
OK
Delete an entry from
the current
phonebook specified
by its position index.
AT+CPBW=2
AT+CPBR=1,10
OK
OK
13.3 General Commands
Display the current network operator
that the handset is currently registered
with.
AT+COPS? +COPS: 0,0,"CHINA
MOBILE"
OK
Display a full list of network operator
names.
AT+COPN +COPN: "20201",
"COSMO"
[skip a bit]
+COPN:
"901012","Maritime Comm
Partner AS"
OK
reduce its functionality. This will
deregister the handset from the network.
AT+IPR?
AT+CFUN=0
[wait for deregister]
ATD6241xxxx;
AT+CFUN=1
+IPR: 0
OK
OK
ERROR
OK

Request the IMSI AT+CIMI 460008184101641
OK
13.4 Call Control Commands
Make a voice call ATD6241xxxx; OK
MS makes a voice call
Hang up a call ATH OK
Call dropped
Make a voice call using the last number
facility. The initial call is established and
then cancelled. The second call is made
using the previous dial string.
ATD6241xxxx;
ATH
ATDL
OK
OK
OK
Example of a MT voice call
Make MT voice call to MS.
ATA
ATH
RING
RING
OK[accept call]
OK[hang up call]
Call related to supplementary service:
AT+CHLD. This Command provides
support for call waiting functionality.
AT+CHLD=<N> Return
value:(0,1,1x,2,2x,3,4,6,
6x,7x,8x,9x)
Terminate current call and accept waiting
call.
Establish a voice call from EVB, receive
an incoming call(incoming call accepts
waiting status), terminate active call and
accept incoming call. Note call waiting
must be active for this option – use
"AT+CCWA=1,1” before running this
demonstration.
AT+CCWA=1,1
ATD6241xxxx;
<RX incoming call>
AT+CHLD=1
OK
OK
RING
+CCWA: "62418148 ",
129,1,""
OK
<waiting call active>
Set current call to busy state and accept
waiting call.
an incoming call(incoming call accepts
waiting status), place active call on hold
and switch to incoming call. Terminate
active call and switch back to original
call. Note call waiting must have been
previously enabled for this
demonstration to work.
ATD6241xxxx;
<RX incoming call>
AT+CHLD=2
AT+CHLD=1
RING
+CCWA: "1391818
6089",129,1,""
OK
<waiting call active other
call on hold>
OK
<incoming call terminated,
dialed number now active>

Switch between active and held calls.
an incoming call (incoming call accepts
waiting status), place active call on hold
and switch to incoming call. Switch
between both calls, placing each in the
hold state whilst the other is active
before terminating each one. This feature
relies on knowing each call’s ID. This is
done using the List Current
Calls(AT+CLCC) Command. A call’s ID
is required to switch between held and
active calls. Held calls are not
automatically resumed when all other
calls are terminated. They need to be
made active using the AT+CHLD=2x
Command. Note call waiting must have
been previously enabled for this
ATD6241xxxx;
<RX incoming call>
AT+CHLD=2
AT+CHLD=21
AT+CLCC
AT+CHLD=22
AT+CHLD=12
AT+CHLD=11
OK
RING
+CCWA: "1391818
6089",129,1,""
OK
<incoming call activated,
original on hold>
OK
<original call activated,
incoming call held>
+CLCC:1,0,0,0,0,"62
418148",129,""
+CLCC:2,1,1,0,0, "139
18186089",129, ""
OK
<Note incoming call held
flag set>
OK
<original call held, incoming
call active>
OK
<terminate incoming call>
<terminate original call>
Send busy status to incoming waiting
caller.
waiting status), send ‘busy’ status to
waiting mobile. Note call waiting must
have been previously enabled for this
ATD6241xxxx;
<RX incoming call>
AT+CHLD=0
OK
RING
+CCWA: "1391818
6089",129,1,""
OK
OK
<incoming call sent busy
msg, current call retained>
Drop all calls on hold.
waiting status), switch to incoming call
and drop all waiting calls.
Note call waiting must have been
previously enabled for this
ATD6241xxxx;
<RX incoming call>
AT+CHLD=2
AT+CHLD=0
OK
RING
+CCWA: "1391818
6089",129,1,""
OK
<incoming call actived,
original on hold>
OK
<incoming call actived,
current call

terminate>
13.5 SIM Toolkit Commands
Select the 1st
menu item: individual
assistance
AT*PSSTK="MENU
SELECTION",1
*PSSTK: "SELECT
ITEM",0,0,,0,0,1,0,0,5
Go to the menu of individual assistance
AT*PSSTK="GET
ITEM LIST",5
*PSSTK: "GET ITEM
LIST",1,1,2,5E2E52A9,0,0,0
*PSSTK: "GET ITEM
LIST",2,2,2,752862377BA174
06,0,0,0
*PSSTK: "GET ITEM
LIST",3,3,2,52067EC47BA17
406,0,0,0
*PSSTK: "GET ITEM
LIST",4,4,2,7FA453D16D886
06F,0,0,0
*PSSTK: "GET ITEM
LIST",5,5,2,65E57A0B63D09
192,0,0,0
OK
Select 1: help AT*PSSTK="SELECT
ITEM",1,1,0,0
*PSSTK:
"NOTIFICATION",1,19,1,2,5
3D190014FE1606F2026,0,0
Go back to main menu AT*PSSTK="NOTIFIC
ATION",1,0
*PSSTK: "END SESSION"
13.6 Audio Commands
DTMF tones AT+CLDTMF=2,
"1,2,3,4,5"
OK
13.7 SMS Commands
Set SMS system into text mode, as
opposed to PDU mode.
AT+CMGF=1 OK
Send an SMS to myself. AT+CSCS="GSM" OK

AT+CMGS="+861391
818xxxx"
>This is a test
<Ctrl+Z>
+CMGS:34
OK
Unsolicited notification of the SMS
arriving
+CMTI: "SM",1
Read SMS message that has just arrived.
Note: the number should be the same as
that given in the +CMTI notification.
AT+CMGR=1 +CMGR: "REC UNREAD",
"+8613918186089", "","02
/01/30,20:40:31+00"
This is a test
OK
Reading the message again and change
the status to "READ” from ”UNREAD”
AT+CMGR=1 +CMGR: "REC READ",
"+8613918186089","",
"02/01/30,20:40:31+00"
This is a test
OK
Send another SMS to myself. AT+CMGS="+861391
818xxxx"
>Test again<Ctrl+Z>
+CMGS:35
OK
Unsolicited notification of the SMS
arriving
+CMTI: "SM",2
List all SMS messages.
Note:”ALL” must be in uppercase.
AT+CMGL="ALL" +CMGL: 1, "REC
READ","+8613918186089",
"", "02/01/30,20:40:31+00"
This is a test
+CMGL: 2, "REC
UNREAD"," ",
"+8613918186089", ""
,"02/01/30,20:45:12+00"
Test again
OK
Delete an SMS message. AT+CMGD=1 OK
List all SMS messages to show message
has been deleted.
AT+CMGL="ALL" +CMGL: 2, "REC READ",
"+8613918186
089","","02/01/30,20:45:12+
00"
Test again

OK
Send SMS using Chinese characters AT+CSMP=17,167,2,
25
AT+CSCS="UCS2"
AT+CMGS="0031003
300390031003800310
038003x003x003x003
x"
>4E014E50<Ctrl+Z>
OK
OK
+CMGS:36
OK
13.8 GPRS Commands
Establish a GPRS context. Setup modem driver
Setup dial up
connection with *99#
Run internet explorer
Should be able to surf the
web using Internet explorer.
There are two GPRS Service Codes for
the ATD Command: Value 88 and 99.
Establish a connection by service code
99.
Establish a connection by service code
99 and using CID 1
ATD*99#
ATD*99***1#
CONNECT
CONNECT
Check if the MS is connected to the
GPRS network
Detach from the GPRS network
Check if the MS is connected to the
GPRS network
AT+CGATT?
AT+CGATT=0
AT+CGATT?
+CGATT:1
OK
OK
+CGATT: 0
OK
Check the class of the MS AT+CGCLASS? +CGCLASS:B
OK
Establish a context using the terminal
equipment: defines CID 1
and sets the PDP type to IP, access
AT+CGDCONT=1,
"IP","CMNET"
ATD*99#
OK
CONNECT

point name and IP address aren’t set.
Cancel a context using the terminal
equipment
Pause data transfer and enter Command
mode by +++
Stop the GPRS data transfer
AT+CGDCONT=1,
"IP","CMNET"
ATD*99#
+++
ATH
OK
CONNECT
OK
OK
Reconnect a context using the terminal
equipment
Resume the data transfer
AT+CGDCONT=1,
"IP","CMNET"
ATD*99#
+++
ATO
OK
CONNECT
OK
CONNECT
*Quality of Service (QOS) is a special parameter of a CID which consists of several parameters itself.
The QOS consists of
The precedence class
The delay class
The reliability class
The peak throughput class
The mean throughput class
And is decided in "requested QOS” and "minimum acceptable QOS”.
All parameters of the QOS are initiated by default to the "network subscribed value (=0)" but the
QOS itself is set to be undefined. To define a QOS use the AT+CGQREQ or AT+CGQMIN
Command.
Overwrite the precedence class of
QOS of CID 1 and sets the QOS of
CID 1 to be present
AT+CGQREQ=1,2 OK
Response: all QOS values of CID 1
are set to network subscribed except
precedence class which is set
to 2
AT+CGQREQ +CGQREQ:1,2,,,,
+CGQREQ: 3,0,0,3,0,0
OK
Set the QOS of CID 1 to not present.
Once defined, the CID can be activated.
AT+CGQREQ=1 OK
Activate CID 1, if the CID is already
active, the mobile returns OK at once.
If no CID is defined the mobile responds
+CME ERROR: invalid index.
Note: If the mobile is NOT attached
by AT+CGATT=1 before activating, the
AT+CGACT=1,1
AT+CGACT=1,3
OK
+CME ERROR: requested
service option not
subscribed.

attachment is automatically done by the
AT+CGACT Command.
Use the defined and activated CID
to get online. The mobile can be
connected using the parameters of
appointed CID or using default
parameter
AT+CGDATA="PPP",
1
CONNECT
The mobile supports Layer 2 Protocol (L2P) PPP only.
Note: If the mobile is NOT attached by AT+CGATT=1 and the CID is NOT activated before
connecting, attaching and activating is automatically done by the AT+CGDATA Command.
Some providers require using an APN to establish a GPRS connection. So if user uses the
Microsoft Windows Dial-Up Network and ATD*9… to connect to GPRS, user must provide the
context definition as part of the modem definition (Modem
properties/Connection/Advanced…/Extra settings.) As an alternative, user can define and activate
the context in a terminal program (e.g. Microsoft HyperTerminal) and then use the Dial-Up
Network to send only the ATD Command.

Contact us:
Shanghai SIMCom wireless solutions Ltd.
Address: Building A, SIM Technology Building, No. 633 Jinzhong Road, Shanghai,
P. R. China 200335
Tel: +86 21 3252 3300
Fax: +86 21 3252 2030
URL: www.sim.com/wm

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