What is instruction format in computer architecture?

Answer 1

The connection between the hardware and software components of a computer creates the computer architecture. It is basically how the components are connected to form a complete system. Sir Frederick P. Brooks and Sir Lyle R. Johnson presented the idea of computer architecture in 1959.

A set of operating codes, operands, an opcode, and an addressing mode make an instruction. The instruction format is the standard instruction format that is directly used by the CPU.

The instruction format is just the sequence of bits (0,1). The group of these bits is called a field. Each field of the system provides specific information for a particular task to the CPU about the instruction's operation and the instruction's data. The most fundamental difficulty in format design is instruction length. The longer the command will, take longer the time to fetch it.

The types of Fields are discussed below:

1. Operation Field: It specifies the operations that are performed by the instructions like, ADD, SUB, etc. It can be any value or number on which the task has been performed. Operation field is mandatory for every instructor

2. Address Field: It specifies the address of the operand. It refers to the address where the operand is stored.

On the basis of multiple address fields, the instruction is categorised as follows:

1. Zero address instruction: The operand positions are implicitly represented in zero address instructions. The stack-organized computer system supports these commands.

2. One address instruction: This instruction manipulates data with the help of an implicit accumulator. Accumulator is a register that performs a logical process for the CPU. It uses one address field.

3. Two address instructions: This address instruction is mostly used. This address command format has three operand fields. In the two address sections, registers or memory addresses can be used.

4. Three address instructions: A three-address command must contain three operand components in its format. These three fields could be registers or memory locations.

The instruction pipeline in computer architecture

The instruction pipeline in computer architecture shows the system's instruction flow. It has 4 major segments, which are discussed below.

Segment 1: The instruction fetch part can be performed using first in, first out (FIFO) buffers.

Segment 2: The second section decodes the memory-fetched command before the effective location is computed in a different arithmetic circuit.

Segment 3: The input is fetched from memory.

Segment 4: The execution of the instructions is performed.

Some of the features of instruction are :

1. Addressing model: This is the first part of the instruction format. Data over the instruction format can be represented as an addressing format, and data is stored in the computer's memory or in the CPU's register

2. OPCODE(operation code): This is the second part of the instruction format, and the opcode instructs the processor to perform the desired operation.

3. Operand: Depending upon the processor instruction format, it contains zero to three operands, and this part specifies the data or points to the address of the data.

Answer 2

a basic computer has three instruction code format-memory-refrence,resister-refrece,and input-outputinstruction.

each format consist of 16bits.