Siemens SIMATIC ET 200SP Manual page 23

Byte 1: "Status type" variant
Table 5- 7
Bit no.
7
6...0
Byte 2: Slot number
Slot number (1...n) of the slave module
0 is the placeholder for the overall device.
Byte 3: "Interrupt specifier" variant
Table 5- 8
Bit no.
7...3
2
1...0
Communication module CM DP (6ES7545-5DA00-0AB0)
Manual, 12/2014, A5E33619758-AB
Structure of byte 1 of the device-specific diagnostics ("Status type" variant)
Value Meaning
1 Status message
Status_Type
0 - Reserved -
1 Status message
2 Module_Status (see also bytes 4...62)
3...31 - Reserved -
32...126 Vendor-specific
127 - Reserved -
Structure of byte 3 of the device-specific diagnostics ("Interrupt specifier" variant)
Seq_No Unique identification of an alarm message
Add_Ack If this bit is set, the DP V1 master indicates that this interrupt
expects an acknowledgment in the form of a WRITE job.
Alarm_Specifier
0 No further distinction
1 Interrupt appears, slot is disrupted
The slot generates an interrupt due to an error.
2 Interrupt disappears, slot is OK
The slot generates an interrupt and indicates that there is no other
error.
3 Interrupt disappears, slot is still disrupted
The slot generates an interrupt and indicates that errors remain.
Diagnostics, error and system alarms
5.4 Device-specific diagnostics with DP-V1
Meaning
Meaning
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