What does the instruction opcode represent?

Each instruction in the instruction system has an opcode, which indicates the nature of the operation that the instruction should perform. Different instructions are represented by different encodings of the opcode field, and each encoding represents an instruction. The number of bits that make up the opcode field generally depends on the size of the computer's instruction set.

Operation code:

refers to the part of the instructions or fields (usually represented by codes) specified in the computer program to perform the operation, which is actually the instruction The sequence number is used to tell the CPU which instruction needs to be executed.

Instructions:

Instructions consist of operation codes and address codes. The opcode indicates the nature of the operation to be performed, that is, what operation to perform, or what to do; the address code is the address of the operation object when the opcode is executed.

Execution of instructions:

When the computer executes a specified instruction, it must first analyze the opcode of this instruction to determine the nature and method of the operation. Only then can other components of the computer be controlled to cooperate to complete the function of command expression. This analysis work is completed by the instruction decoder.

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