ProSoft Technology MVI71-MCM - Manual (Page 94)

MVI71-MCM ♦ PLC Platform Reference
Modbus Communication Module
Page 94 of 111 ProSoft Technology, Inc.
December 28, 2007
5.6.6 Command Control
Register Content Description
7800 Command Code Enter one of the valid control command codes in
this register to control the module (9997, 9998, or
9999). Refer to MVI71-MCM Command Error Codes
(page 94) for more information.
7801 Command Data Not Used
- - -
7999 Command Data Not Used
5.7 MVI71-MCM Command Error Codes
The following tables list the MVI71-MCM Command Error Codes:
5.7.1 Standard Modbus Protocol Errors
Code Description
1 Illegal Function
2 Illegal Data Address
3 Illegal Data Value
4 Failure in Associated Device
5 Acknowledge
6
Busy, Rejected Message
5.7.2 Module Communication Error Codes
Code Description
-1 CTS modem control line not set before transmit
-2 Timeout while transmitting message
-11 Timeout waiting for response after request
253 Incorrect slave address in response
254 Incorrect function code in response
255 Invalid CRC/LRC value in response
5.7.3 Command List Entry Errors
Code Description
-41 Invalid enable code
-42 Internal address > maximum address
-43 Invalid node address (< 0 or > 255)
-44 Count parameter set to 0
-45 Invalid function code
-46 Invalid swap code