Why does PX4 standard firmware not support Frsky telemetry?

Up to now I was flying all my Copters with the PX4 firmware. Now I own a Frsky Q7 and it tried to use Frsky telemetry (yaapu script). Unfortunately the standard PX4 firmware does not support Frsky telemetry. I am not in the position to create a special PX4 firmware because I am not familiar with programming. Why does the standard firmware not include support for Frsky ? I have tested Ardupilot firmware and it works great with Frsky telemetry but in some points I would prefer PX4 firmware because I am more familiar with PX4. Therefore my question why does standard PX4 firmware not support Frsky telemetry?

@hodizu I believe PX4 does support Frsky telemetry. Have you checked the documentation in https://docs.px4.io/master/en/peripherals/frsky_telemetry.html ?

I think you currently need some external hardware to use the Yaapu script with PX4:

Follow the step-by-step instructions on how to do it here.

Good luck.

Thank you to all,

I am familiar with ARDUINO IDE an Arduino board, so I believe I can manage the programming of Teensy board and cabling to Pixhawk Flight controller.


Hi @rollys @Mark_Whitehorn

The PX4 docs suggest using LuaPilot Script and also that the result is you get out-of-the-box support for these message.

Can you help me understand why you would use the Yappu script? I.e. what extra messages does it give you (or other features) that would make a person choose to use this instead?

@rollys Depending on what you guys say, would it make sense to link to or include this in the official docs?

It’s not just a matter of getting the data but more of how they’re presented.

  • The graphical HUD presentation provides you an almost pared down GCS right on the Tx.
  • The LUA takes it to another level with the Horus or Jumper T16 with real-time map integration on another page. I haven’t updated the docs to reflect that setup, but if you watch my video at 2:50 you will see a picture-in-picture of what shows on QGC and the T16 screen. I just updated the thread to include how to configure this.
  • I didn’t switch to the page during the video but you get the visual text messages you normally only get when you have QGC running from bootup to shutdown. You can see it here at 29:33.
  • My implementation here is in air mode, but this could be beneficial and implemented for LRS (long range system) in relay mode.
  • I think one could argue that if it meets one’s need, it could substitute having to carry a laptop for GCS.

I think so and why not, since it’s a working and available option for LUA implementation. I’ve already received permission from Yaapu to publish anywhere as needed so feel free to include it.

Good luck.

It is on my (very long) list. If you create a PR I’ll help review and merge it. Otherwise I will certainly get to this at some point :slight_smile:

Thanks @rollys !

Hi all,
Any news about the FrSky telemetry on px4?
After reading the documentation at the PX4 User Guide - FrSky Telemetry I found as explained here pixhawk-fmuv5-stm32f7-and-later that for a Pixhawk 5X no special cable is required, just connecting the smart port to any enabled serial port (Telem2 in my case).

I checked that FrSky telemetry works:
Screenshot from 2023-05-12 18-13-07

But, when I select “Discover new sensors” from the telemetry tab of my Taranis Q X7, the RC finds lots of meaningless sensors (like F501, F701, etc.). Moreover, I do not see one of the most important for me, the battery voltage (VFAS).

Having no experience with Lua scripts, I thought the values of these sensors would be mapped into something readable by the Lua script. At this point, neither the LuaPilot scrip nor the lua yaapu script worked.

I saw the post here Pixhawk 5x - FrSky Telemetry ID Reference List?, and it seems that the best solution is to give up to FrSky telemetry.

Do you know if there is a way to get correct data from the FrSky telemetry, considering my setup made by a Pixhawk 5X, a Taranis Q X7 RC and an X8R receiver?

Check Post# 4.

You can also look into the MavlinktoPassthrough.

Good luck.

Thank you for your reply.

  1. Is a Teensy 3.2 board still required?

  2. Moreover,

You can also look into the MavlinktoPassthrough.

At that link, you can read:

Passthru protocol telemetry is optional (type=10) on Ardupilot, but not supported by the PX4 flight stack (as at July 2019).

Has nothing changed to date?

Yes, Teensy is required if you’re using it with PX4.

Not that I’m aware of. Keep in mind, the Yaapu LUA was developed for ArduPilot and the Teensy is what gives it the ability to interface with PX4 AutoPilot.

Good luck.