106 • Programmable Field Bus Controller 750-833
Acyclic Communication According to DP/V1
WAGO-I/O-SYSTEM
750
Bus System
The error message
“invalid slot“
is generated when addressing modules that
are neither physically nor virtually (projected as not being connected)
available.
When reading from indices (MSAC1/2_Read), the maximum PDU length that
can be set is 240 bytes. The bus coupler/controller returns the actual amount of
information from the respective index.
When writing to indices (MSAC1/2_Write), the maximum possible length of
information to be written to the respective index must not be exceeded.
Otherwise, the error message
“invalid length while writing!“
is reported by
the bus coupler/controller.
Coding of Error Messages
Bit
7
Bit
7
Bit
7
Bit
7
Octet 1
Octet 3
Octet 4
Octet 2
Error_Frame
Error_Class
Error_Code_1
Error_Code_2
User specific
Error_Decode
Bit
6
Bit
6
Bit
6
Bit
6
Bit
5
Bit
5
Bit
5
Bit
5
Bit
4
Bit
4
Bit
4
Bit
4
Bit
3
Bit
3
Bit
3
Bit
3
Bit
2
Bit
2
Bit
2
Bit
2
Bit
1
Bit
1
Bit
1
Bit
1
Bit
0
Bit
0
Bit
0
Bit
0
Service
Abb. 3.10.2-13: Coding of error messages
g012121e
Octet 2
Error Decode
Meaning
0 ... 127
Reserved
128 PROFIBUS-DP/V1
129 ... 254
Reserved
255 PROFIBUS-FMS