Omron CS1G/H-CPUxxH Instructions Manual page 756

Subroutines
Global Subroutines and
Differentiation
Subroutine functions
divided by task.
An SBS(091) or GSBS(750) instruction can be written within a subroutine
region (SBN(092) to RET(093)) or global subroutine region (GSBN(751) to
GRET(752)) to "nest" subroutines. Subroutines can be nested up to 16 levels.
Interrupt task 0
GSBN 10
GSBS 11
Observe the following precautions when using differentiated instructions
(DIFU(013), DIFU(014), or up/down differentiated instructions) in subroutines.
The operation of differentiated instructions in a global subroutine is unpredict-
able if a subroutine is executed more than once in the same cycle. In the fol-
lowing example, global subroutine 0001 is executed when CIO 000000 is ON
and CIO 000100 is turned ON by DIFU(013) when CIO 000001 has gone
Cyclic or interrupt task
000000
GSBS
n
B
000001
GSBS
m
D
END
Interrupt task 0
GSBN
n
A
GRET
GSBN
m
C
GRET
END
GSBN 11 GSBN 12
to to
GSBS 12
to to
GRET GRET
Section 3-19
Execution
condition ON
B
Execution
condition ON
D
A
C
to
GRET
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