QUESTION:
May I execute block calls for the communications processors CP
34x-5 and CP 343-1 / IT/ PN in multiple runtime layers at the same
time?
ANSWER:
No, it is not permissible to process communications blocks
(SIMATIC_NET_CP library) at the same time in multiple runtime
layers (e.g. OB1 and OB35).
Contrary to the information in the manual "Communications with
SIMATIC" block processing can be interrupted at any time by
organization blocks of higher priority.
If you call the blocks in multiple OBs, you have to make sure at
program level that a running block is not interrupted by another
block for processing the communications processor (e.g. via
Block/release SFC alarms).
Keywords:
Master, Slave, Communications service
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