CHAPTER 9. INSTRUCTION SET

9.4.5Increment/Decrement Instructions

INCS reg

Function: reg reg + 1; Skip if reg = 0

Increments the contents of register reg (X, A, H, L). When the contents of register reg become 0 as the result of incrementing, skips the next instruction.

INCS mem

Functions: (mem) (mem) + 1; Skip if (mem) = 0, mem = D7 to D0 : 00H to FFH

Increments the data memory contents addressed by 8-bit immediate data mem. When the data memory contents become 0 as a result of incrementing, skips the next instruction.

DECS reg

Function: reg reg - 1; Skip if reg = FH

Decrements the contents of register reg (X, A, H, L). When the contents of register reg become FH as a result of decrementing, skips the next instruction.

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NEC PD75402A, PD75P402 user manual Incs reg, 166