Siemens SIMATIC Operating Instructions Manual page 149

Channel-Specific Diagnostics Starting at Byte 20 to Byte 31 for F-Switch
The channel-specific diagnostics start in byte 20 of the diagnostic data. Four bytes of
diagnostic information are provided per channel.
Figure A-12
Due to the different numbers of channels of the F-modules, data record 1 has differing
lengths:
8/16 F-DI
4/8 F-DI/4 F-DO
F-Switch
ET 200pro Distributed I/O System - Fail-Safe Modules
Operating Instructions, 05/2007, A5E00394073-02
Channel-Specific Diagnostics Starting at Byte 20 of the Diagnostic Data of the F-Switch
Diagnostic Data of Fail-Safe Modules
40 bytes
44 bytes
32 bytes
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