Siemens SIMATIC Operating Instructions Manual page 142

Diagnostic Data of Fail-Safe Modules
Data Records 0 and 1 of the System Data
The diagnostic data of a module can be up to 44 bytes long and is located in data records 0
and 1 of the system data area:
● Data record 0 contains 4 bytes of diagnostic data that describe the state of the F-module.
● Data record 1 contains
Description
The structure and content of the individual diagnostic data bytes are described below.
In general, the following applies: If a fault occurs, the corresponding bit is set to "1".
Bytes 0 and 1
The following figure shows the content of bytes 0 and 1 of the diagnostic data.
Figure A-1
142
– The 4 bytes of diagnostic data of the F-module that are also in data record 0 and
– Up to 40 bytes of channel-specific diagnostic data depending on the F-module (see
Channel-Specific Diagnostics Starting at Byte 8"
"
Bytes 0 and 1 of Diagnostic Data
).
ET 200pro Distributed I/O System - Fail-Safe Modules
Operating Instructions, 05/2007, A5E00394073-02