I managed to get the rs485 work as a "raw" output TTY by putting the RS485 config to "Over IP" in the web interface after updating the RUT955 to the latest firmware ...07.12... I also noticed gliches on the RS485 bus with an oscilloscope this was due to the fact that.... Somebody have routed the damn transmit enabled pin to the data pin! What did Teltonika think here?!? This is NOT proper, i even opened the RUT955 open to confirm my suspicion and concluded that this was the case, result = usable but GLITCHY bus! If you run the RUT955 close to 115200 BAUD this will be particularly bad!
If one routes the TX pin to the TX_EN pin the transceiver will create a glitch every time an logical '1' is send to the pin activating the transmission circuitry, please fix this! the TX_EN pin should be activated separately as a function of available data in the shift register of the CPU so that TX_EN stays at a logical '1' for the whole duration of the bytes being shifted out from the buffers.
Teltonika you can do better, please revise this!
R.