Mumbai University > Computer Engineering > Sem-5 > Microprocessor

Marks: 5

Year: May 2015

Features:

1. It is a high performance numeric co-processor.

2. It can work on integer, decimal and real type numbers.

3. It has an instruction set capable of doing complex arithmetic and trigonometric calculations.

4. It follows IEEE Floating Point Standard.

Block diagram:

It consists of following blocks:

I) Control Unit:

 It receives all instructions for the NDP.

 Instructions involving the register stack are given to the NEU, while the control unit executes the remaining instructions.

 Its main components are:

a. Instruction Queue.

b. Control Word.

c. Status Word.

d. Instruction Pointer.

e. Data Pointer.

II) Numeric Execution Unit:

 Instructions involving the register stack are executed by the NEU.

 It uses operands from register stack.

 During arithmetic operations, 8087 handles exponents and mantissas separately.

 Example: For addition, it will first compare and equalize the exponents by shifting, and only then add the mantissa.

 Its main components are:

a. Register Stack.

b. Tag Word.