8086 bascis register with pin diagram explanation
- 5. Features 8085 Microprocessor 8086 Microprocessor Basic Design An 8-bit microprocessor capable of processing 8-bit data. A 16-bit microprocessor capable of processing 16-bit data. Size of Arithmetic Logic Unit (ALU) The 8085 features an 8-bit ALU. The 8086 features a 16-bit ALU. Maximum Accessible Memory Can access up to 216 bytes or 64kb of memory. Can access up to 220 bytes or 1MB of memory. Clock Frequency The 8085 has an on-chip oscillator with a frequency of 3MHz. The 8086 comes in three versions with clock frequencies of 5MHz, 8MHz, and 10MHz. Address Bus Size The 8085 has an 8-bit address bus. The 8086 has a 16-bit address bus. Cost The 8085 is relatively cheaper than the 8086. The 8086 is comparatively more expensive than the 8085 Support for Pipelining The 8085 does not support pipelining. The 8086 supports pipelining. Processor Configuration The 8085 is a single processor configuration microprocessor. The 8086 is a multiprocessor configuration microprocessor. Instruction Queue The 8085 does not have an instruction queue. The 8086 has a 16-bit instruction queue principle. Operation,Flage,Memory segmentation...
- 6. 8 AH AL BH BL CH CL DH DL SP BP SI DI AX BX CX DX Pointer Index 8 bits 8 bits 16 bits Accumulator Base Count Data Stack Pointer Base Pointer Source Index Destination Index 8086 MICROPROCESSOR HIGHLIGHTS
- 7. Architecture 8086 Microprocessor Sl.No. Type Register width Name of register 1 General purpose register 16 bit AX, BX, CX, DX 8 bit AL, AH, BL, BH, CL, CH, DL, DH 2 Pointer register 16 bit SP, BP 3 Index register 16 bit SI, DI 4 Instruction Pointer 16 bit IP 5 Segment register 16 bit CS, DS, SS, ES 6 Flag (PSW) 16 bit Flag register 8086 registers 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0 OF DF IF TF SF ZF AF PF CF
- 8. 4 Intel 8086 Internal Architecture
- 9. Architecture 8086 Microprocessor Register Name of the Register Special Function AX 16-bit Accumulator Stores the 16-bit results of arithmetic and logic operations AL 8-bit Accumulator Stores the 8-bit results of arithmetic and logic operations BX Base register Used to hold base value in base addressing mode to access memory data CX Count Register Used to hold the count value in SHIFT, ROTATE and LOOP instructions DX Data Register Used to hold data for multiplication and division operations SP Stack Pointer Used to hold the offset address of top stack memory BP Base Pointer Used to hold the base value in base addressing using SS register to access data from stack memory SI Source Index Used to hold index value of source operand (data) for string instructions DI Data Index Used to hold the index value of destination operand (data) for string operations Registers and Special Functions
- 10. Features 1 0 • It is a 16-bit μp. • 8086 has a 16 bit data bus and 20-bit address bus • • It has four segments It provides 14 registers, 16 -bit length. • Word size is 16 bits • It has multiplexed address and data bus AD0- AD15 and A16 – A19.
- 11. Memory Segmentation Code segment (64KB) Data segment (64KB) Extra segment (64KB) Stack segment (64KB) 1 MB The memory in an 8086 based system is organized as segmented memory. The CPU 8086 is able to address 1Mbyte of memory. The Complete physically available memory may be divided into a number of logical segments. 00000 FFFFF Physical Memory
- 12. Pins and Signals 8086 Microprocessor Common signals AD0-AD15 (Bidirectional) Address/Data bus Low order address bus; these are multiplexed with data. When AD lines are used to transmit memory address the symbol A is used instead of AD, for example A0-A15. When data are transmitted over AD lines the symbol D is used in place of AD, for example D0-D7, D8-D15 or D0-D15. A16/S3, A17/S4, A18/S5, A19/S6 High order address bus. These are multiplexed with status signals