Siemens SIMATIC S7-1200 - Page 1256

Communication processor and Modbus TCP
13.8 Legacy Modbus TCP communication
S7-1200 Programmable controller
1256 System Manual, V4.2, 09/2016, A5E02486680-AK
Table 13- 134 MB_CLIENT execution condition codes
1
STATUS
(W#16#)
MB_CLIENT parameter errors
7001 MB_CLIENT is waiting for a Modbus server response to a connect or disconnect request, on the assigned
TCP port. This is only reported for the first execution of a connect or disconnect operation.
7002 MB_CLIENT is waiting for a Modbus server response to a connect or disconnect request, for the assigned
TCP port. This will be reported for any subsequent executions, while waiting for completion of a connect
or disconnect operation.
7003
A disconnect operation has successfully completed (Only valid for one PLC scan).
80C8 The server did not respond in the assigned time. MB_CLIENT must receive a response using the transac-
tion ID that was originally transmitted within the assigned time or this error is returned. Check the connec-
tion to the Modbus server device.
This error is only reported after any configured retries (if applicable) have been attempted.
8188
Invalid mode value
8189
Invalid data address value
818A
Invalid data length value
818B Invalid pointer to the DATA_PTR area. This can be the combination of MB_DATA_ADDRESS +
MB_DATA_LEN.
818C
Pointer to a optimized DATA_PTR area (must be a non-optimized DB area or M memory area)
8200
The port is busy processing an existing Modbus request.
8380
Received Modbus frame is malformed or too few bytes have been received.
8387 The assigned
Connection ID parameter is different from the ID used for previous requests. There can only
be a single Connection ID used within each MB_CLIENT instance DB.
This is also used as an internal error if the Modbus TCP protocol ID received from a server is not 0.
8388 A Modbus server returned a quantity of data that is different than what was requested. This applies to
Modbus functions 15 or 16 only.
1
In addition to the MB_CLIENT errors listed above, errors can be returned from the
underlying T block communication instructions (TCON, TDISCON, TSEND, and TRCV
(Page 857)).