Exception Codes; Exception Handling; E.1 Exception Handling - Siemens SITRANS FC410 Operating Instructions Manual

Exception codes

E.1

Exception handling

There is a defined set of exception codes to be returned by slaves in the event of problems.
All exceptions are signalled in the response from the slave by adding 80 hex to the function
code of the request and following this byte by an exception code.
Table E- 1
Exception
code (dec)
01
02
03
04
FC410 with Modbus
Operating Instructions, 02/2016, A5E33120874-AC
Exception codes
Exception text
Illegal function
Illegal data address
Illegal data value
Slave device failure
Description
The function code received in the query is not an allowable
action for the slave
The data address received in the query is not an allowable
address for the slave.
A value contained in the query data field is not an allowable
value for the addressed location. This may indicate a fault in
the structure of the remainder of a complex request, such that
the implied length is incorrect or the number of registers is too
high.
The request is for some other reason not acceptable. It may
e.g. indicate that the data value to write is evaluated to be
beyond limits.
E
149