No Serial Tab in QGroundControl

I’m totally new to PX4, QGroundControl, and the Pixhawk 4 board itself. I am trying to setup MAVLink telemetry from the TELEM1 port. I know that this port is configured by default for MAVLink telemetry, and QGroundControl talks to the board without any problems when connect to the computer through an FTDI breakout. However, I want to change the baudrate to something slower than 57600, as my next step is to hook up an HC-12 to the port and have wireless telemetry. The lower baudrate will improve range greatly due to the way the receiver works on the HC-12.

The problem is that I can’t find any Serial parameters anywhere in QGroundControl. I’m pretty sure that according to the documentation the tab should be in the parameters section, but I don’t see it. Also, there are only minimal parameters available in the MAVLink and GPS sections. Does anyone know why this is happening? Or what I need to do to get the parameters/Serial tab to appear?

EDIT: The GPS still works though. The position, # of satellites, and compass all seem to work.

Thanks!

UPDATE
I never figured this out, but I just configured TELEM2 (with the available parameter) to do telemetry at 57600 baud, and everything works fine, ableit with less range than could be achieved with a lower baud rate.

1 Like

Are you using the 1.8 release or the master branch? After the 1.8 release some changes were made to be able to configure both TELEM1 and TELEM2.

I’m using the 1.8 release.

If you switch to master you will be able to configure TELEM1 and TELEM2. Otherwise in the 1.8 release you can only configure TELEM2.

Excuse my jumping in, but I am also bedevilled by missing parameters in QGC, and the Serial parameters are also missing. I am missing FRSKY_TEL…
Can you explain further how I “switch to master”??
I’ve been extremely frustrated chasing this for many hours, and would appreciate a further nudge!

When you buy a Pixhawk you usually receive it with the latest PX4 release. Currently the Pixhawk 4 is being sold with the 1.8 release. Between two releases many things are added to the firmware and this can be seen on the PX4 GitHub repository (https://github.com/PX4/Firmware). The master branch contains all the new features/bug fixes from contributors. The serial port parameters you are talking about were introduced after the 1.8 release (which is the latest PX4 release). In the 1.8 release you could only set the baudrate on the telem 2 port using the SYS_COMPANION parameter, but the TELEM1 baud rate was fixed to 57600 (typical rate for telemetry radios). Recently the uart architecture was changed a bit. These changes will be in the next release but if you need them now you can either build your own code (https://dev.px4.io/en/setup/getting_started.html) or flash the binary of the master GitHub branch via qgc. On qgc you can go to the firmware tab and flash the developer version that will contain the most recent binary. Let me know what is still not clear that I can further explain it.

Alright. I’ll try that this weekend (I’m just in 9th grade so I don’t have much time in the evenings).

Cool. Let me know if you have any other questions to get your vehicle together.