The document provides an overview of the Arduino platform for beginners.
- 2. Microcontroller CPU + ++++++++++ Microprocessor CPU (on single chip) Microcontrollers 2
- 3. What is a Microcontroller Integrated chip that typically contains integrated CPU, memory (RAM ROM), I/O ports on a single Chip. System on a single Chip/ small computer on a single chip Designed to execute a specific task to control a single system Smaller & Specified (design cost) Differs from Microprocessor general-purpose chip Used to design multi purpose computers or devices Require Multiple chips to handle various tasks Typically Microcontroller embedded inside some device Microcontrollers are important part of Embedded systems 3
- 4. What is a Development Board • A printed circuit board designed to facilitate work with a particular microcontroller. • Typical components include: • power circuit • programming interface • basic input; usually buttons and LEDs • I/O pins 4
- 5. The Arduino Development Board 5 Arduino (The name is an Italian , meaning “strong friend”) is an open- source platform used for building electronics projects. Arduino consists of both a physical programmable circuit board (often referred to as a microcontroller) and a piece of software, or IDE (Integrated Development Environment) that runs on your computer, used to write and upload computer code to the physical board.
- 6. Arduino Microcontroller Boards Microcontroller ATmega328 Operating Voltage 5 V Input Voltage (recommended) 7-12 V Input Voltage (limits) 6-20 V Digital I/O Pins 14 (of which 6 provide PWM output) Analog Input Pins 6 DC Current per I/O Pin 40 mA DC Current for 3.3V Pin 50 mA Flash Memory 32 KB (ATmega328) of which 2 KB used by bootloader SRAM 2 KB (ATmega328) EEPROM 1 KB (ATmega328) Clock Speed 16 MHz 6
- 8. ATmega328 Microcontroller Pin number Pin name Special function 8
- 9. Microcontroller Ports and Pins The communication channels through which information flows into or out of the microcontroller Ex. PORTB Pins PB0 – PB7 May not be contiguous Often bi-directional C 9
- 11. Setting the Pin Data Direction Arduino pinMode(pin_no., dir) Ex. Make Arduino pin 3 (PD3) an output pinMode(3, OUTPUT); Note: one pin at a time Suppose you wanted Arduino pins 3, 5, and 7 (PD3, PD5, and PD7) to be outputs? Is there a way to make them all outputs at the same time? Yes! Answer coming later… 11
- 12. Atmega328 Overview 12 8-bit CPU Timer/Counter Internal memories 32KB Flash 1KB EEPROM 2KB SRAM Serial Peripheral Interface Universal Synchronous and Asynchronous serial Receiver and Transmitter (Serial) GPIO 2-wire Serial Interface
- 13. AVR Microcontroller AVR stand for? Advanced Virtual RISC, the founders are Alf Egil Bogen Vegard Wollan RISC AVR architecture was conceived by two students at Norwegian Institute of Technology (NTH) and further refined and developed at Atmel Norway (Atmel AVR). 13
- 14. AVR Microcontroller AVR Micro controllers is Family of RISC Microcontrollers from Atmel. There are multiple architectures RISC (Reduced Instruction Set Computer) CISC (Complex Instruction Set Computer) 14
- 15. RISC Microcontroller Reduced Instruction Set Computers Advantages Fast Execution of Instructions due to simple instructions for CPU. RISC chips require fewer transistors, which makes them cheaper to design and produce. Emphasis on software Single-clock , reduced instruction only Register to register: “LOAD" and "STORE“ are independent instructions Spends more transistors on memory registers 15
- 17. The AVR is a Harvard architecture CPU. Harvard Architecture Computer architectures that used physically separate storage and signal pathways for their instructions and data. CPU can read both an instruction and data from memory at the same time that makes it faster. von Neumann architecture CPU can Read an instruction or data from/to the memory. Read, Write can`t occur at the same time due to same memory and signal pathway for data and instructions. AVR Microcontroller 17
- 18. Harvard Architecture AVR Microcontroller Harvard Architecture diagram 18
- 19. AVR Microcontroller AVR is a family of 8-bit microntrollers with a large range of variants differing in: - size of program-memory (flash) - size of EEPROM memory - number of I/O pins - number of on-chip features such as UART and ADC Smallest microcontroller is the ATTiny11 with 1k flash ROM, no RAM and 6 I/O pins. Large such as the ATMEGA128 with 128k flash, 4KB RAM, 53 I/O pins and lots of on-chip features. 19
- 21. AVR Architecture • Registers • Instruction Set • I/O ports • Memory (flash & RAM & ROM) • CPU 21
- 22. AVR Architecture Registers: Two types of registers GERNEL purpose & SPECIAL purpose registers GERNEL purpose 32 general purpose registers having storage capacity of 8-Bits Named as R0,R1,R2 to R31. Register 0 to 15 & 16 to 31 are different. Can store both Data & Addresses. SPECIAL purpose: Three registers Program counter Stack Pointer Status Register 22
- 23. 23 AVR Memory Space • Program Flash – Vectors, Code, and (Unchangeable) Constant Data • Working Registers – Includes X, Y, and Z registers. • I/O Register Space – Includes “named” registers • SRAM – Data Space – Runtime Variables and Data – Stack space • EEPROM space – For non-volatile but alterable data
- 24. AVR Architecture Pointer Register Three 16-bit address registers pairs of registers 26 to 31 have extra meaning in AVR assembly. X (r27:r26), y (r29:r28), z (r31:r30). pointer Sequence X Read/Write from address X, don't change the pointer 24
- 25. AVR Architecture status register (SREG) It is 8-bit long each bit has a different meaning. I: Global Interrupt Enable/Disable Flag, SREG7 T: Transfer bit used by BLD and BST instructions, SREG6 H: Half Carry Flag, SREG5 S: For signed tests Instruction Set, SREG4 V: Two's complement overflow indicator, SREG3 N: Negative Flag, SREG2 Z: Zero Flag, SREG1 C: Carry Flag, SREG0 I Z T N H S V C 25
- 26. AVR Architecture Stack Pointer (SP) 16-bit stack pointer (SP) holds address in data space of area to save function call information. 26
- 28. AVR Architecture Memory: There are two separate memories Program Memory Data Memory 28
- 29. AVR Studio Integrated Development Environment (IDE) for writing and debugging AVR applications for windows environments. AVR Studio provides a project management tool, source file editor, chip simulator and In-circuit emulator interface for the powerful AVR 8-bit RISC family of microcontrollers. 29