ProSoft Technology MVI56-AFC - Manual (Page 243)

MVI56-AFC ♦ ControlLogix Platform MVI56-AFC Sample Logic
Liquid and Gas Flow Computer User Manual
ProSoft Technology, Inc. Page 243 of 316
February 25, 2011
The valid Modbus error codes are listed below:
Error Description
=0 No error
>0 Modbus exception code or communication error
Modbus exception codes are issued by the responding slave and listed in
commonly available Modbus protocol manuals; they lie between 1 and 127,
and include:
1 Illegal function
2 Illegal address
3 Illegal data value
Communication errors are issued by the AFC:
Error Description
500 CTS timeout
501 Receive timeout
502 Bad framing
503 Buffer overrun
504 Bad checksum/CRC
505 Wrong slave
506 Wrong function code
507 Wrong length
<0 Configuration, parameter, or logic error:
-1 Master Port not configured
-2 Master Port never used
-3 Bad Slave Address
-4 Bad Direction/Target
-5 Bad Datum Size/Swap Options
-6 Bad number of data items