Technical data

The three diagnostic groups are distinguished by the header or identification
bytes. The order of the groups is unimportant. Each group can also occur
more than once.
Device-related diagnostics
The evaluation of the device-related diagnostics can be found in the
documentation for the device. This information varies from vendor to
vendor.
ID-related diagnostics
In ID-related diagnostics, the list following the header byte contains a bit
reserved for every configured module (ID).
This list indicates the ID number for which diagnostic data exist (bit "1").
The list of ID-related diagnostics is rounded up to a byte boundary.
Non-configured modules are indicated by "0".
Bit 01234567
Header byte for the data field
(group) device-related diagnostics
Field length in bytes (incl. header
byte) 2 to 63
0
0
Identification for
device-related diagnostics
:
:
2nd byte
xth byte
(Field length can also be "0")
:
:
Fig. 11.29 Structure of the Header Byte for Device-Related Diagnostics
B8976060/02 Distributed I/Os (DP)
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