Appendix E.2.1. Example: Fc 6 = Write Single Register; Appendix E.3. Read/Write Operation - FieldServer FS-8700-01 Driver Manual

FS-8700-01 Modbus RTU/ASCIIFS-8700-01_Modbus_RTU Driver Manual
For Address_Type Modicon_5digit
Address range Data_Type
40001 - 49999 Single_Register
30001 - 39999 Single_Coil
Appendix E.2.1. Example:
Add a parameter to the Modbus client side Map Descriptor called Data_Type.
If you specify the Data_Type as Single_Register and the Function as WRBC or WRBX, then a Modbus poll with FC 6
will be generated.
Logically Single Register implies a length of one, and even if you try to set the length longer in the csv file, the
length is limited to 1 in the driver.

Appendix E.3. Read/write Operation

When using the driver as a Modbus master, the function RDBC allows read/write capability with Register and Coil
data types. If defaults are used, then Function codes 5 and 6 (Single Writes) are used to write data back to the
registers being read, regardless of data length being read. If multiple writes (FC 15 and 16) are needed for
Read/write operation, the user needs to specify the Node_Type parameter in the Client Side Nodes Section and set
it to Block_Mode.
Note that block writes of length 1 are currently all that is supported.
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Function Code (Write)
6
5
FC 6 = Write Single Register
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