Siemens SENTRON PAC3100 - Exception Codes; Table A- 6 MODBUS Exception Codes; A.2.4 Exception Codes

Appendix
A.2 Modbus RTU
SENTRON PAC3100
Manual, 07/2009, A5E02385159B-01
129
A.2.4 Exception codes
Overview
Table A- 6 MODBUS exception codes
Exception codes Name Meaning Remedy
01 Illegal
Function
Illegal function:
• The function code in the
request is not a permissible
action for the slave.
• The slave is in a status in which
it cannot process a request of
this type. This is the case, for
example, if it has not yet been
configured and is requested to
return register values.
Check which function
codes are supported.
02 Illegal Data
Address
Illegal data address
This address is not permissible for
the slave. This is the case, for
example, if the combination of start
offset and transfer length is invalid.
Check the offset and the
number of registers.
03 Illegal Data
Value
Illegal data value:
The request contains a data value
that is not permissible for the slave.
This indicates an error in the
remaining structure of a complex
request, e.g. an incorrect data
length.
Check that the specified
offset and the specified
data length in the
command are correct.
04 Slave Device
Failure
Error in processing the data:
An indefinite error occurred when
the slave attempted to execute the
requested action.
Check that the specified
offset and the specified
data length are correct.