Omron SYSMAC CJ - REFERENCE MANUAL 01-2008 Reference Manual page 868

Subroutines
and CIO 000100 is turned ON by DIFU(013) when CIO 000001 has gone
from OFF to ON. If CIO 000001 is ON in the same cycle, global subroutine
0001 will be executed again but this time DIFU(013) will not detect the rising
edge of CIO 000001 and CIO 000100 will be turned OFF.
Cyclic task 1
000000
Cyclic task 2
000001
Interrupt task 0
000001
In contrast, the output of a differentiated instruction (DIFU(013) or DIFD(014))
would remain ON if the instruction was executed and the output was turned
ON but the same global subroutine was not called a second time.
In the following example, global subroutine 0001 is executed if CIO 000000 is
ON. Output CIO 000100 is turned ON by DIFU(013) when CIO 000001 has
gone from OFF to ON. If CIO 000000 is OFF in the following cycle, subrou-
tine 0001 will not be executed again and output CIO 000100 will remain ON.
GSBS
1
GSBS
1
GSBN
1
DIFU
000100
GRET
Section 3-19
Executed
again
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