Omron SYSMAC CJ - REFERENCE MANUAL 08-2008 Reference Manual page 456

Increment/Decrement Instructions
Flags
Examples
416
of the specified words is decremented only when the execution condition has
gone from OFF to ON.
Wd+1
The Equals Flag will be turned ON if the result is 0000 0000, the Carry Flag
will be turned ON when a digit changes from 0 to F, and the Negative Flag will
be turned ON if bit 15 of Wd+1 is ON in the result.
Both the Carry Flag and the Negative Flag will be turned ON when the content
changes from 0000 0000 to FFFF FFFF.
Name Label
Error Flag ER
Equals Flag =
Carry Flag CY
Negative Flag N
Operation of – –L(593)
In the following example, the 8-digit hexadecimal content of D00101 and
D00100 will be decremented by 1 every cycle as long as CIO 000000 is ON.
Wd+1: D00101
Operation of @– –L(593)
The up-differentiated variation is used in the following example, so the content
of D00101 and D00100 will be decremented by 1 only when CIO 000000 has
gone from OFF to ON.
− −L
@
Wd+1: D00101
Wd
OFF
ON if the result is 0000 0000 after execution.
OFF in all other cases.
ON if a digit in Wd+1 or Wd went from 0 to F during exe-
cution.
OFF in all other cases.
ON if bit 15 of Wd+1 is ON after execution.
OFF in all other cases.
Decremented every cycle
while CIO 000000 is ON.
Wd: D00100 Wd+1:
−1
: Execution of − −L(593)
Decrement Decrement Decrement
Decremented only
for up-differentiation.
Wd: D00100 Wd+1:
−1
: Execution of @ − −L(593)
Decrement Decrement
Section 3-10
Wd+1 Wd
Operation
D00101 Wd: D00100
Decrement
D00101 Wd: D00100