cFP2020 rs485 2-wire

[FeArne]

Hello,

I've to connect a cFP2020 controller with a temperature controller via RS485 in 2-wire mode (tcontrollers interface). The datatransfer is done (if RS485 works ;-)))) by MODBUS protocol using RTU mode (cFP-master, CAL9400-slave). To initialize the serial port (Com4 cFP), I shortened the adequate lines on the RJ-45 connector and tried to initialize the port in LabWiew, using the Property Node Function to switch to the 2wire/Auto tranceiver mode (write). Now if I tried to run this initialization, I always got an error at property node 😞
Has anyone an idea to avoid this error message ?

[Ben]

From my reading of the user manual for the cFP 2020, it sounds like that not supported.

The fine print says that you can use the port wired as two wire but you have to filter out the echos explicitly. They also say this is not recommended.

That is just my read in the subject.

Did you try skipping this set-up step and see if you can still talk?

Ben