I'm new to the RS485 communication protocol.
I am trying to communicate with a Siemens SINAMICS V20 VFD with the Unitronics Unistream PLC ( USP-070-B10)
The VFD leads to a 3 phase motor
I set up the baud rate to 9600, data bit to 8, parity list to none, and stop bit to 1
In addition I set up a remote slave in COM1 of Masters drop down, in MODBUS
In the slave configuration I made a coil named "motor" that writes to address 40 every 100 ms
I spoke with a Siemens Technician about the driver settings, and could not find a setting to "ECHO" bits to the driver
I was told I need to set a transmit telegram
The is there an FC03 for "read holding register" or a way to "Echo" data to 40,100 (MODBUS)?
Any sort of references or suggestions for setting up communication?