Question

Briefly describe the main functionality of the program counter register (PC), the instruction register (IR), and the execute process of an instruction in a computer.

Answer 1

Explanation:

program counter:

• it is also known as instruction pointer.
• it has the address of the instruction that is being executed at that time.

• it is a 32-bit register .

instruction register:

• it keeps the instruction that is being executed at that time.
• it holds active memory that is currently executed

execute process:

it is based on 3 cycles:

1. fetch
2. decode
3. execute

fetch:

it takes the instruction from program counter(has memory address)

decode:

the instruction that is fetched is decoded/interpreted  by the decoder.

execute:

The result generated by the operation is stored in the main memory or sent to an output device