Operands and Opcodes

Operands

• Definition: Operands are the data or values that are used by an instruction.
• Types:
  • Registers: Operands stored in registers.
  • Memory Locations: Operands stored in memory locations.
  • Immediate Values: Operands that are specified directly in the instruction.

Opcodes

• Definition: Opcodes (Operation Codes) are the part of an instruction that specifies the operation to be performed.
• Function: Opcodes tell the processor what operation to perform, such as addition, subtraction, or load.
• Examples:
  • ADD: Addition operation.
  • SUB: Subtraction operation.
  • MOV: Move data from one location to another.

Instruction Format

• Opcode + Operand(s): A typical instruction format consists of an opcode followed by one or more operands.
• Example: ADD R1, R2 (Add the contents of register R2 to register R1).

Importance

• Instruction Execution: Opcodes and operands are essential for instruction execution.
• Processor Design: Understanding opcodes and operands is crucial for designing processors.
• Programming: Knowledge of opcodes and operands is necessary for low-level programming.