Siemens CM 1542-5 Operating Instructions Manual page 41

Byte 3: Variant "Status specifier"
Table 5- 8
Bit no.
7...2
1...0
Bytes 4...62: Module-specific diagnostics: General coding
This byte contains data with module-specific information that is described in the relevant
module documentation. The relevant module is identified by the slot (byte 2).
Bytes 4...62: Module-specific diagnostics with "status type" and "module status"
With the variant "status type" of the device-specific diagnostics of DP-V1 slaves (see byte 1,
bit 7) and the setting "Modul_Status" (see byte 1, bits 0...6), there are two status bits here for
each slot (= module). Bits not required are set to 0.
Table 5- 9
Byte
4
5
...
62
The status bits are coded as follows:
Table 5- 10
Value
00
01
10
11
CM 1542-5
Operating Instructions, 11/2018, C79000-G8976-C290-04
Structure of byte 3 of the device-specific diagnostics (variant "status specifier")
- reserved -
Status_Specifier
0
1
2
3
Structure of the bytes for module-specific diagnostics data
Bit 7 6
Module status 4
Module status 8
...
Module status 236
Meaning of the values of the status bits
Meaning
Data valid
Data invalid - error (for example short-circuit)
Data invalid - wrong module
Data invalid - no module plugged in
5.4 Device-specific diagnostics in DP-V1
Meaning
No further distinction
Status appears
Status disappears
- reserved -
Bit assignment
5 4
Module status 3 Module status 2
Module status 7 Module status 6
...
Module status 235 Module status 234
Diagnostics and upkeep
3 2 1
Module status 1
Module status 5
...
Module status 233
0
...
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