Siemens ET 200pro Operating Instructions Manual page 205

Structure of channel-specific diagnostic data
The number of channel-specific diagnostic events is limited to 9. The length of slave
diagnostic data is determined by the number of current channel-specific diagnostic data. If
more than 9 channel-specific diagnostic events are pending, bit 7 "diagnostics overflow" is
set in station status 3.
The figure below shows the structure of channel-specific diagnostic data if diagnostic events
are selected in the configuration.
Figure 9-6
ET 200pro distributed I/O system
Operating Instructions, 03/2013, A5E00335544-08
Structure of channel-specific diagnostic data
Alarm, error and system messages
9.1 PROFIBUS DP
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