The Decrement Instruction operates on counters only, and will effectively subtract 1 from the counter. This instruction does not update any flags.
Hex Mnemonic Action
8110 ; DEC PC PC - 1 -> PC
8120 ; DEC SP SP - 1 -> SP
8150 ; DEC X X - 1 -> X
Updates when Executed:
- The appropriate counter or index register.
This instruction will only work on counters, and will increment that counter in one clock-cycle.