Inovance H3U Series - H3 U Subprogram Execution Mechanism

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12
12 Subprogram
12.1 Overview
12.1.2 H3U Subprogram Execution Mechanism
The following gure shows the execution logic and cyclic scan mode of the main program and subprograms.
Main program
Interrupt
subprogram
Internal processing
Call subprogram
SBR_
subprogram
Return
CALL
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Layers of nested subprograms
A maximum of six subprograms can be nested. The main program calls a subprogram as the rst layer.
One layer is added each time a subprogram is called. If a subprogram has returned, no layer is added, as
shown in the following gure.
1 2 3 4
5 6
Main program
Internal processing
Trigger subprogram
Subprogram
Return
Subprogram
Subprogram
Subprogram
Subprogram
Subprogram
CALL or interrupt
trigger