A microprocessor is an integrated circuit (IC) which incorporates core functions of a computers central processing unit (CPU). It is a programmable multipurpose silicon chip, clock driven, register based, accepts binary data as input and provides output after processing it as per the instructions stored in the memory.

1. You as an IT consultant of a company APUSyst is required to do research, analyse and evaluate the best microprocessor to be used for your clients company. Compare and analyse between 8088 and 8086 processor in terms or their internal architecture, execution unit, bus interface unit, performance and other criteria that can be used to evaluate the performance of the processor. Justify your finding with the aid of diagrams, tables etc as the supporting details. Your research also needs to include on how to improve the processor performance and the implication after upgrading. (40 marks)

1. Given below are the instructions set of 8086 processor. Analyse the codes manually or you may use debugger to check the operation of instruction with processor. Tabulate your answer in table form to get the values in each register before instruction executed and after the execution.

1. MOV AX, 1234h

MOV BX, 256h

MUL BX

1. MOV AX, 3333h

MOV BX, 2h

DIV BX

Sol151:

a. Comparison between 8088 and 8086 processors:

Internal Architecture: The 8088 processor is an 8-bit microprocessor, while the 8086 processor is a 16-bit microprocessor. The 8086 has a 20-bit address bus, which allows it to address up to 1 MB of memory, while the 8088 has an 8-bit data bus and a 20-bit address bus, which limits it to addressing up to 640 KB of memory.

Execution Unit: The 8086 processor has a more powerful execution unit than the 8088. It can execute more instructions in a single cycle and has a wider range of addressing modes.

Bus Interface Unit: The 8088 processor has a simpler bus interface unit than the 8086, which makes it less expensive to manufacture. However, the 8086 has a more advanced bus interface unit that allows it to access memory more quickly.

Performance: Overall, the 8086 processor has better performance than the 8088 due to its wider data bus, more powerful execution unit, and advanced bus interface unit.

Improvement of Processor Performance: The performance of both the 8088 and 8086 processors can be improved by increasing the clock speed, adding a math coprocessor, or upgrading the memory.

Implication after upgrading: After upgrading, the processor will be able to handle more complex tasks and execute instructions more quickly, which can improve overall system performance and productivity.

b. Analysis of the instruction set of 8086 processor:

i. MOV AX, 1234h Before execution: AX=0, BX=0 After execution: AX=1234h, BX=0 Explanation: This instruction moves the hexadecimal value 1234h into the AX register and leaves the BX register unchanged.

MUL BX Before execution: AX=1234h, BX=0 After execution: AX=0000h, BX=0 Explanation: This instruction multiplies the value in the AX register (1234h) by the value in the BX register (0) and stores the result in the AX register. Since the result is larger than 16 bits, the higher 16 bits of the result are stored in the DX register. In this case, the result is 0, so both AX and DX are set to 0.

ii. MOV AX, 3333h Before execution: AX=0, BX=0 After execution: AX=3333h, BX=0 Explanation: This instruction moves the hexadecimal value 3333h into the AX register and leaves the BX register unchanged.

DIV BX Before execution: AX=3333h, BX=0 After execution: AX=0000h, BX=0 Explanation: This instruction divides the value in the AX register (3333h) by the value in the BX register (0). Since division by zero is undefined, this instruction generates a divide-by-zero exception and the program will terminate.