Help controlling linear actuator with Arduino Uno


I am new to Arduino but I have done other projects using Raspberry Pi. Currently, I need help controlling a linear actuator with an Arduino Uno. The actuator in question is the Linak LA18A. The Linak protocol can be viewed here: Linak Protocol.

This actuator makes use of identifier 37 and reference 8. The only way I have of connecting to the actuator is with an RJ-45 port. The lin information is transferred on pin 6 of the port. Right now I have pin 6 and the GND pin connected to this: Lin Bus breakout board which uses the MCP2004A Lin chip. The breakout board is connected to the Arduino UNO like so: GND -> Analog GND, TX -> Digital 0 (RX), RX -> Digital 1 (TX).

According to the Linak spec, this LIN protocol does not use a SYNC byte and from what I can tell, my breakout board is supposed to act as the LIN slave.

The problem I am running into is I cannot seem to read any data from the breakout board or send any data with any intelligible response. The baud rate is 19200 and when reading the RX pin all I see is 1 repeatedly even when nothing is connected to the pin.

Does anyone know how I can send data to this actuator or read what is coming in?

I know WHAT needs to be sent (0x0b, 0x00, 0xcf when id 0x25 is seen), I just am having a hard time sending it.

Thank you very much for your help!

First of all: how do you debug the transmitted values? The Uno only has one Serial device, which can be used either for USB or external serial communication, but not both. If your breakout board connects to RX and TX, you cannot use Serial for debugging.

For an exploration of serial connections I'd use a Mega with 4 Serial devices in hardware, so that Serial can be reserved for debugging while Serial1 etc. are free for further connections.