Omron SYSMAC CJ - REFERENCE MANUAL 08-2008 Reference Manual page 450

Increment/Decrement Instructions
Flags
Examples
410
(@++(590)) is used, the specified word is incremented only when the execu-
tion condition has gone from OFF to ON.
The Equals Flag will be turned ON if the result is 0000, the Carry Flag will be
turned ON when a digit changes from F to 0, and the Negative Flag will be
turned ON when bit 15 of Wd is ON in the result.
Both the Equals Flag and the Carry Flag will be turned ON when the content
of Wd changes from FFFF to 0000.
Name Label
Error Flag ER OFF
Equals = ON if the content of Wd is 0000 after execution.
Flag
OFF in all other cases.
Carry Flag CY ON if a digit in Wd went from F to 0 during execution.
OFF in all other cases.
Negative N ON if bit 15 of Wd is ON after execution.
Flag
OFF in all other cases.
Operation of ++(590)
In the following example, the content of D00100 will be incremented by 1
every cycle as long as CIO 000000 is ON.
Operation of @++(590)
The up-differentiated variation is used in the following example, so the content
of D00100 will be incremented by 1 only when CIO 000000 has gone from
OFF to ON.
@++
Wd Wd
Operation
Incremented every cycle
while CIO 000000 is ON.
Wd: D00100 Wd:
0 0 1 9
: Execution of ++(590)
Increment Increment
Incremented only for
up-differentiation.
Wd: D00100 Wd: D00100
0 0 1 A
0 0 1 9
: Execution of @++(590)
Increment
Section 3-10
D00100
0 0 1 A
Increment Increment
Increment