Creating The Missing (F-)Blocks; Program Structure - TR-Electronic CD 75 Serie Gesamt-Bedienungsanleitung

Safety Program Creation - Configuration Example

4.4 Creating the missing (F-)blocks

The blocks that have already been automatically created can be viewed in the
Project tree in the directory tree of the device.
All fail-safe blocks are shown with a yellow background to distinguish them from
blocks of the standard user program.

4.4.1 Program structure

The safety program is accessed by calling up the F-Organization Block FOB_RTG1
(OB123). This cyclically calls up the F-function block Main_Safety_RTG1 (FB1)
with its F-data block Main_Safety_RTG1_DB (DB1) with a cyclic interrupt.
Cyclic interrupt OBs have the advantage that they interrupt the cyclic program
processing in OB 1 of the standard user program at fixed time intervals, i.e. in a cyclic
interrupt OB the safety program is called up and processed at fixed time intervals.
After the safety program has been processed, the standard user program is further
processed.
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08/06/2021