Use of SERIAL 1 port to communicate between RPi and a serial device in the vehicle

Hello all,

I’m trying to get communication with an RS232 device in our vehicle.
I saw topic: Connecting Ping Sonar via Navigator Serial Port - Blue Robotics Software / Ping Viewer - Blue Robotics Community Forums
That enabled us to stop BlueOS/Mavlink from using the port (ttyS0), but we cannot get any of our
communication to work over this port.

All data is local to the vehicle. It is not directly used by the Topside/QGC.

Are there any other settings that need to be modified to allow us to pass-through the data over

thanks again,

Mark K

Hi @mark -
This guide may be helpful - can you confirm the serial data you’re trying to connect is at the correct voltage level? (3.3v)
Can you share a screenshot of your bridge configuration, and what you’re trying to accomplish with the serial data? Or are you trying to read the serial data from the terminal in BlueOS? You likely need to take the red-pill in order to do so…
Finally, I’d recommend trying Serial port 3 or 4 to see if that can correct your issue.

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Thanks for the information. We will attempt to communicate via a bridge.

We are running some code, running on RPi, not in blueOS, that is not under our control that uses serial communications.

Their code uses the normal RS232 communication interface on the RPi.

Is there a way we can pass-through their coms without having them change their code?

Thanks again for your help,

Mark K

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Hi @mark
The information you’re after is in the guide I linked in the previous post! You can connect the serial data coming from your Pi to the Pi running BlueOS, and setup a bridge to relay the communications across the communications link to the vehicle. Otherwise, once you remove the serial port from the Autopilot’s control, you should be able to open a serial terminal and view the serial stream locally within BlueOS. Take the red-pill at the terminal, and run:
screen /dev/tty*** 115200

Replace tty*** with the serial port you have connected, and 115200 with the baud rate. When you push enter you’ll see serial data! To exit push cntrl-a, followed by the letter k to kill the screen session.