Modbus address mapping definitions
Location
<WorkspaceDirectory>\DataFiles\xio.Modbus.AddressMappingDefinitions.dat
Standard Modbus memory addresses start with address 0. To use a different addressing scheme, address mapping is possible.
These additional address mappings are be specified in this file. For each Modbus device, an individual address mapping can be specified.
The structure of the Modbus address mapping definition file is as follows:
' Modbus address mapping definition file' ' Mapping Name;Offset for Discrete Input;Offset for Coil;Offset for Input Register;Offset for Holding Register RegisterNumber;1;1;1;1 FunctionCode;20001;10001;40001;30001
 col |  Parameter | type | Description |
---|---|---|---|
1 | Mapping Name | Â string | The name of the mapping. This name is used within the Modbus Device Definition file to identify the mapping. The mapping name must be unique. |
2 | Offset for Discrete Input | Â number | This offset specifies the number that is subtracted from the Discrete Input addresses that are used in the Modbus Datapoint Defintion file. E.g. if the offset is 20001 and the datapoints address 20010 is used, the Modbus interfaces reads the Discrete Input at memory address 9. |
3 | Offset for Coil | Â number | This offset specifies the number that is subtracted from the Coil addresses that are used in the Modbus Datapoint Defintion file. E.g. if the offset is 20001 and the datapoints address 20010 is used, the Modbus interfaces reads the Discrete Input at memory address 9. |
4 | Offset for Input Register | Â number | This offset specifies the number that is subtracted from the Input Register addresses that are used in the Modbus Datapoint Defintion file. E.g. if the offset is 20001 and the datapoints address 20010 is used, the Modbus interfaces reads the Input Register at memory address 9. |
5 | Offset for Holding Register | Â number | This offset spec- ifies the number that is subtracted from the Holding Register addresses that are used in the Modbus Datapoint Defintion file. E.g. if the offset is 20001 and the datapoints address 20010 is used, the Modbus interfaces reads the Holding Register at memory address 9. |