Chapter 2, Problem 2.11E

Program Plan Intro

R-Type instruction:

• All the data values used by the instruction are located in registers that time R instruction is used.
• R-type instruction is used by the register-to-register arithmetic (add, sub, and so on).

op

rs

rt

rd

shamt

func

       6 bits         5 bits         5 bits         5 bits         5 bits        6 bits

Where,

op – it is an opcode used to selects a particular operation.

rs and rt – are the first and second source registers.

rd – it is the destination register.

shamt – it is only used for shift instruction.

func – it is used together with “op” to choose an arithmetic instruction.

I-Type instruction:

• When the instruction must operates on a register value and an immediate value that time I instruction is used.
• I-type instruction is used by the load, store, branch and immediate instructions.

op

rs

rt

address

       6 bits       5 bits         5 bits              16 bits

Where,

op – it is an opcode used to selects a particular operation.

rs and rt – are the first and second source registers.

address – it is a 16 bits signed 2’s complement value.