Hi, I am not familiar with speed controllers but, I have battled with the 750-652.
Maybe this helps for coding:
https://www.wago.community/t/modbus-rtu-ecockpit-pfc100-750-8100-750-652/1530/3
When Importing the 750-652 in your Codesys Project there are three different types #8|#24|#48. Default for the 750-652 is 24 byte width. This can be changed with I/O Configurator just like other modules.
The 750-652 is just RS-485/232 so you’ll need the WagoAppPlcModbus library to properly build modbus queries.
If you just have one Modbus RTU device you can use the FbMbMasterSerial and populte it with the disired queries. But this is limited since you can only create one query.
I prefer the MutliMaster/DigitalTwin way as described in the link above.
You basically instanciate a FbMbMasterMultiQuerySerial and configure baudrate, timeout, databits, stopbit, parity etc.
Then you build the digital twin, wich contains all the modbus queries like read input registers 45 to 65 with their FC etc. and map the Response to an Output and vice versa with inputs.
after that instanciate your digital twin and connect it to the FbMbMasterMultiQuerySerial. This will add the queries to a “list” that will be sequencially handled by the FbMbMasterMultiQuerySerial.
In this german forum is a example programm wich may help:
https://www.sps-forum.de/threads/serial-schnittstelle-750-562-modbus.112182/#post-885015
I hope this helps.
Godspeed