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How to change an uart port protocol to Mavlink?

Hi guys, I’m trying to connect a jetson nano to a pixhawk mini. The mini only has one telemetry port which I’m going to be using for the radio antenna to communicate with the ground station. I read in some other blog that you can still use a different port as long as it is serial to connect to a companion computer, and then change the port’s potocol to Mavlink. I’m still a new guy in this whole subject so I would highly appreciate any detailed feedback/guidance on how to approach this whole situation. Thanks in advance.

Hi,

the Holybro Pixhawk mini only has one UART/serial port. There is no other port accessible, except for the micro USB port.
So you could connect the companion computer to USB, but the vibrations during operation might damage the micro USB connector or the PCB.
The solution I would suggest is, to connect the companion computer to the UART of the Pixhawk mini and the telemetry radio to the companion computer. Then install mavlink-router, cmavnode or mavproxy to forward telemetry to your GCS.

First at all Thanks a lot for your response. This is my first time posting a question in this forum. Basically what you are saying is connect my Jetson nano to the UART port of the mini. Also connect the telemetry radio antenna on the nano itself and establish communication with the GCS ?

If what I’m saying is correct, what of the telemetry port on the pixhawk mini ? Since I connecting my Jetson to the pixhawk via UART port wouldn’t it be ok to just connect the radio antenna to the pixhawk mini unique telemetry port ?

I hope I’m making myself understandable and also properly getting what you are saying.

Thanks again for the time.

There is only one port (leaving the USB out of consideration). The UART port can be configured to be used for different purposes, like GPS, telemetry, different sensors, etc.

I might be skipping something but referring back to your solution. How do I tell the Nano from the software side that uart port on the pixhawk mini is the one I want to establish communication with ? I ask this because I read from some other blog that I have to change the uart port’s protocol to mavlink on the nano. But don’t exactly know how to do it.

You need to use some kind of software on the nano to send/receive mavlink packages to/from the pixhawk. There is software that only acts as a relay between the pixhawk and one or more GCS PC/Laptops i.e. The ones I mentioned above, cmavnode and mavlink-router are an example for that. Mavproxy is a full flegded GCS software, which can be used from the commandline, but can also be used as a relay.
Than there is software like dronekit-python or ROS, which you can use to expand your vehicles abilities with computer vision, alternative non GPS navigation methods and more, if you know how to do it. I do not know about any premade companion computer OS images for the jetson nano, so you might have to install everything that you need by yourself.
The software above is often combined, so you could use a relay to fork the mavlink telemetry to dronekit or ROS running on the nano and send it to your GCS at the same time.

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