Exception Responses - Woodward easYgen-2000 Series User Manual

Application
Modbus Applications > Exception Responses
Fig. 241: Write register - resetting the
default values
6.6.3

Exception Responses

Modbus exception responses
Code Name
01 ILLEGAL FUNCTION
02 ILLEGAL ADDRESS
03 ILLEGAL DATA VALUE
Table 91: Modbus - exception responses
450
Fig. 240: Modscan32 at address 410418
1. Use the "display options" to set the value format to decimal.
2. Double-click the address to issue a Write Register com‐
mand.
ð Fig. 241 shows how the parameter is enabled using the
ModScan32 Software. The value must be set to "1" to
enable the parameter.
The Modbus protocol has multiple exception responses to show
that a request could not be executed. Exception responses can be
recognized if the response telegram contains the request function
code with an offset of 128 (0x80 hex).
Ä "Modbus - exception responses" Table on page 450 explains
possible reasons for an exception response that occurred.
Reason
The sent request function code is not supported by the Modbus protocol.
Permission to read/write the parameter is denied.
The amount of requested registers is wrong to read/write this registers.
The data value exceeds the min. and max. limitations of the parameter
upon a write request.
There is no parameter on the requested address.
easYgen-2200/2500 | Genset Control 37535B