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17. Instruction Components


  • Instruction in memory has two parts: opcode and operands.

  • The opcode identifies the operation that instruction does

  • The operands are subjects of the operation, such as data values, registers, or memory addresses.

  • Due to variety of opcodes and operands, instructions may occupy different sizes of bytes in memory.

  • Instructions with no operands can have implied operands, those that are not explicitly shown.

  • Instruction formats:

      Instruction formats

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