Chapter 3 Deployment
3-20
Diagnostic functions
Profibus DP provides an extensive set of diagnostic functions for quick
error localization. Diagnostic messages are transferred via the bus and
collected by the master.
The diagnostic messages that are created by the Profibus slave have,
depending on the parameterization, a length of 122byte.
As soon as the Profibus slave sends a diagnostic to the master, the max. of
122byte diagnostic data are prepended by 6byte standard diagnostic data:
Byte 0 ... 5
Standard diagnostic data:
Is only prepended at transfer to the master via
Profibus
x ... x+8
Identifier-related diagnostic
x ... x+19
Module status
max. 21
⋅
(x ... x+2)
Channel-related diagnostic
x ... x+19
Interrupt
May be enabled or
disabled via
parameterization
At the transfer of a diagnostic to the master the slave standard diagnostic
data are prepended to the diagnostic bytes. More detailed information to
the structure of the slave standard diagnostic data is to find in the standard
papers of the Profibus User Organization.
The slave standard diagnostic data have the following structure:
Standard diagnostic
Byte
Bit 7 ... Bit 0
0
Bit 0: Bit is always at 0
Bit 1: slave is not yet ready for exchange data
Bit 2: Configuration data does not correspond to
actual
configuration
Bit 3: External slave diagnostic available
Bit 4: Request function is not supported by slave
Bit 5: 0 (fix)
Bit 6: Wrong parameterization
Bit 7: 0 (fix)
1
Bit 0: New parameters have to be assigned to slave
Bit 1: Statistic Diagnostic
Bit 2: 1 (fix)
Bit 3: Response monitoring has been enabled
Bit 4: "FREEZE" control command received
Bit 5: "SYNC" control command received
Bit 6: reserved
Bit 7: 0 (fix)
2
Bit 6 ... 0: reserved
Bit 7: Diagnostic data overflow
3
Master address after parameterization
FFh: Slave has not been parameterized
4
Ident number High Byte
5
Ident number Low Byte
Structure of the
FS2-GW-DP00
diagnostic data
Standard
diagnostic data
Manual ELCO Intelligent I/O-FS200