Sfcthrd.SFC parallel steps

Product : ISaGRAF V3

Date : 11-September-1996

File : Sfcthrd.SFC parallel steps - actions blocks.htm

Subject : SFC parallel steps - actions blocks

Keywords: SFC - parallel steps - action blocks - recursivity

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SFC steps of one ISaGRAF application are not executed in

different threads.

Although two steps are active at the same time, their

respective action blocks are operated one after the other

within one target sample (PLC loop).

This implies there is no problem of re-entrance on called

functions or sub-programs.

An ISaGRAF function or sub-program is not re-entrant,

and cannot include a call to itself.

Recursive calls are not supported by the ISaGRAF target

system.

All local variables of a sub-program are stored in fixed

memory (static life time).

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