Siemens SIMATIC ET 200M Operating Instructions Manual page 202

Interrupt, error and system messages
9.1 PROFIBUS DP
9.1.3.8 Channel-specific diagnostics
Definition
The channel-related diagnosis gives information about channel errors of modules and
represents detailed information for the identifier-related diagnosis.
The channel-related diagnosis starts according to the module status or the H status.
The channel-related diagnosis does not influence the module status.
Important: the diagnostic interrupt must be switched on for each module!
Channel-releated diagnostics
The channel-related diagnosis is then included in the diagnostic frame only if you have
enabled "enhanced diagnosis" in the configuration. The maximum number of channel-related
diagnoses is restricted by the maximum overall length of the slave diagnosis of 64 bytes with
IM 153-1 or 96 bytes with IM 153-2. The length of the slave diagnosis depends on the
number of current channel-specific diagnosis.
Tip: If, when configuring the ET 200M, you block the interrupts, then up to 29 bytes interrupt
part is also available for the channel-related diagnoses.
Note
Errors that affect all the channels of a module (e.g. the supply voltage of the module fails)
will be portrayed in the channel-related diagnosis only on channel 0.
This then reduces the number of channel-related diagnoses and prevents a "diagnostic
overflow".
200
Operating Instructions, 12/2008, EWA-4NEB780600602-08
ET 200M