Difference between revisions of "Operand"

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(Examples)
 
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  0001:4C 00 10  JMP $1000      ; Moves the program counter to $1000.
 
  0001:4C 00 10  JMP $1000      ; Moves the program counter to $1000.
  
In this example, [[DEX]] is the opcode, but there is not operand since it is implied from the opcode.
+
In this example, [[DEX]] is the opcode, but there is no operand since it is implied from the opcode.
  
 
  0001:CA        DEX            ; Decrements the X index register.
 
  0001:CA        DEX            ; Decrements the X index register.
 +
  
 
[[Category: Guides]]
 
[[Category: Guides]]
 
[[Category: Assembly]]
 
[[Category: Assembly]]

Latest revision as of 20:16, 24 March 2016

An operand is the data portion of a 6502 assembly instruction. This is to be distinguished from the opcode, which specifies the operation to perform.


Examples

In the example below, JMP is the opcode, $1000 is the operand, and the two combined is the instruction.

0001:4C 00 10  JMP $1000      ; Moves the program counter to $1000.

In this example, DEX is the opcode, but there is no operand since it is implied from the opcode.

0001:CA        DEX            ; Decrements the X index register.