Omron CS1G/H-CPUxxH Instructions Manual page 742

Subroutines
Subroutines can be nested up to 16 levels. Nesting is when another subrou-
tine is called from within a subroutine program, such as shown in the following
example, which is nested to 3 levels.
SBN 10
SBN 11
RET
Execution condition ON
Main program
Subroutine
program
(SBN(092) to
RET(093))
SBN 11 SBN 12
SBS 12
RET
RET
Execution condition ON
Main program
Subroutine
Execution condition ON
program n
Two-level
nesting
Subroutine
program m
Program end
Section 3-19
Program end
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