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Entry type: FAQ, Entry ID: 2795485, Entry date: 08/23/2001

Block calls for communications processors in multiple runtime layers

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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?

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).

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