Pixracer PX4 - Using Teensy MavLink Telemetry for FrSky Taranis

Hi there,

on Arducopter I loved this Teensy MavLink Telemetry Solution for FrSky Taranis:

Since PX4 uses the MavLink Protocol as well, in theory the same solution should work for the PX4 flightstack as well. But unfortunatly it does not work. :hushed:
I believe this is because the Telemetry-Port has to be ā€œconfiguredā€ in the right way. For Arducopter the settings are depicted here: Home Ā· Clooney82/MavLink_FrSkySPort Wiki Ā· GitHub

Can someone please tell me how to configure that for PX4?
Can I use QGC to configure both Telem-Ports on the Pixracer?

I know that Pixracer has a dedicated FrSky Interface but it only provides a very limited number of interesting telemetry data values whereas this solution reads about 21 sensors/values.

Thank you in advance!
careyer

2 Likes

@kd0aij Might be interesting to look at what is missing in terms of telemetry values.

@LorenzMeier : Would be fantastic if PX4 would support this directly (probably even without Teensy). However you have to consider that the ā€œSensor namesā€ have to match each other:

How the FrSky ā€œsensorsā€ are named and what data is feed to them via the Teensy MavLink->FrSky transcoder can be derived from the project Wiki as well.
https://github.com/Clooney82/MavLink_FrSkySPort/wiki/1.2.1-Telemetry-Value-Overview

So far this is the most advanced Telemetry solution for Taranis yet. Using it is really really convenient and fun. I would hate to have to go back and flash Arducopter again in order to use it.
Thanks! :grinning:

@LorenzMeier: In the meanwhile - Is there a way to configure the TELEM1 or 2 -Port on PX4 accordingly to the desired settings like in Arducopter? Since both speak ā€œMavLinkā€ this must somehow work.

Thanks in advance.

The docs were lacking, I created this page - does that help?
http://px4.io/docs/mavlink-peripherals/

Thank you for complementing the documentation. Unfortunatly it did not help. :expressionless:
As far as I understood these settings affect the TL2 Port on the Pixracer board only (TL1 unaffected).

I tried all 5 settings without success. As far as I understand the Teensy initially polls the flightcontroller to send specific parameters via MavLink. I can see this initial request via the LED briefly lighting up on the Teensy. Then nothing happens anymore.

Connected to a Pixhawk v2 with AC3.3 the request of the Teensy is followed by the LED rapidly flashing, indicatng that it receives data. Somehow this ā€œhandshakeā€ seems to fail on PX4

Furthermore we developed a Raspberry based All-in-One WiFi solution (realtime HD Video and OSD downlink + MavLink Command Uplink). Works flawlessly using a Pixhawk with AC3.3 and these settings:

  • SERIAL2_PROTOCOL 1
  • SERIAL2_BAUD 57
  • SR2_EXT_STAT 2
  • SR2_EXTRA1 8
  • SR2_EXTRA2 2
  • SR2_EXTRA3 0
  • SR2_PARAMS 2
  • SR2_POSITION 2
  • SR2_RAW_CRTL 0
  • SR2_RAW_SENS 0
  • SR2_RC_CHAN 0

OSD and MavLink Control Uplink do not work at all with PX4 yet - regardless which of the 5 presets we tried.
Correct cabling and connections have been double checked already.

Wouldnā€™t it make sense to implement a 100% Arducopter compatible/identical way to configure the serial Ports for PX4?
There are tons of MavLink peripherals out there which need very specific parameters and settings in order to work properly. I am not sure if one can give good coverage for all those solutions with 5 presets?

Many Thanks for the excellent Support and Help in Advance! :grinning:

I use the Teensy solution as well and couldnā€™t set it up.

I flashed my auav-x2, witch has a full functioning teensy system with the px4 firmware and the telemetry still work perfectly. Only downside is that the lua script is for apm so I donā€™t get the flightmode back to my taranis from the fc. But everything else (bat, gps, hdop, etcā€¦) is displayed on my taranis.

I donā€™t know on the pixracer, but with the Firmware it worksfine!

On a normal pixhawk the telemetry for X-Type Receiver does not work also:
After booting, the app is not running.
Started manually a D-type receiver is detected, although a X8 receiver is connected.
SYS_COMPANION is set to Telemetry. With APM firmware hardeware works perfectly.

street foodstreet food

Can anyone tell me where this has been left off? I have a prototype I need to build using this PixRacer if possible. I need to run Crossfire (900mhz) and 2.4g video. I need to have video (using ezcap) and telemetry sent back to Mission planner (using Bluetooth on Crossfire). Is this all possible with the Pix Racer or should I movbe up to PixHawk? Its needed to be in a small platform.

Thanks!

Meanwhile i use arduplane firmware instead of px4-stack for a long time. With arduplane Mavlink via Crossfire works as well as Frsky telemetry on Pixracer. Since I have no 2.4GHZ Crossfire FPV equipment, I can not comment on that.

Regards Rolf

you can amend the LUA script, using the Pixracer output