DEC loc16
6-84
DEC loc16 Decrement by 1
SYNTAX OPTIONS OPCODE OBJMODE RPT CYC
DEC loc16 0000 1011 LLLL LLLL X − 1
Operands loc16 Addressing mode (see Chapter 5)
Description Subtract 1 from the signed content of the location pointed to by the “loc16”
addressing mode:
Flags and
N
After the operation if bit 15 of [loc16] is 1, set N; otherwise, clear N.
Modes
Z
After the operation if [loc16] is zero, set Z; otherwise, clear Z.
C
If the subtraction generates a borrow, C is cleared; otherwise C is set.
V
If an overflow occurs, V is set; otherwise V is not affected.
Repeat This instruction is not repeatable. If this instruction follows the RPT
instruction, it resets the repeat counter (RPTC) and executes only once.
Example ; VarA = VarA − 1;
DEC @VarA ; Decrement contents of VarA
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