ABB FSCA-01, User Manual

Page: 73 / 90

Communication protocol 73
Exception codes
The adapter module supports the Modbus exception codes shown
below.
Communication profiles
Modbus is an application layer messaging protocol. It describes
how data is transferred between a master and a server, but not the
meaning of that data. Communication profiles are used to define
the meaning of the data.
Exception
Code
Name Description
01h ILLEGAL FUNCTION The function code received in the
query is not an allowable action for
the server.
02h ILLEGAL DATA
ADDRESSS The data address received in the
query is to an allowable address
for the server.
03h ILLEGAL DATA VALUE A value contained in the query data
field is not an allowable value for
the server.
04h SLAVE DEVICE
FAILURE An unrecoverable error occurred
while the server was attempting to
perform the requested action.
06h SLAVE DEVICE BUSY The server is engaged in
processing a long-duration
command. The master should
retransmit the message later when
the server is free.