FrSky Telemetry

This article describes how to transmit vehicle information from the autopilot and display it on an FrSky transmitter (“FrSky Telemetry”).


This article explains a number of approaches for getting information from the autopilot to an FrSky transmitter (including the Taranis).


Native FrSky Telemetry Support

ArduPilot provides a driver that can directly output the FrSky protocol. This section explains how you can connect and configure a Pixhawk to communicate with a D-Receiver or X-Receiver.


  • This feature is only officially supported on the Pixhawk (running AC3.2 or higher) but there is a DIY solution for the APM2.x here.
  • These instructions are largely based upon information from the Pixhawk website.
  • These instructions were written and tested for OpenTX 2.0.x. They have been re-validated against OpenTx 2.1.3 and AC 3.3.2.

D-Receiver setup

For the D-Receiver setup you will need:

D-Receiver cables

Craft and Theory Pixhawk to FrSky Telemetry Cable (D4R-II receiver)

The Pixhawk to FrSky Telemetry Cable (D4R-II receiver) from Craft and Theory is a cost effective “turnkey” cable solution.

Craft andTheory: Pixhawk to FrSky D4R-II receiver cable

DIY Cable for D receivers

You can make your own cable using the following components:


X-Receiver setup

For the X-Receiver setup you will need:

X-Receiver cables

Craft and Theory Pixhawk to FrSky Telemetry Cables

Craft and Theory supply cost-effective all-in-one X-receiver cables with different connectors for the various X-receivers:

DIY Cable for X receivers

You can make your own cable using the following components:


FrSky Telemetry setup in Mission Planner

To enable the FrSky Telemetry output on the Pixhawk’s Telem2 port, please connect with the Mission Planner and then open the Config/Tuning | Full Parameter List page and set the SERIAL2_PROTOCOL parameter to “3” for D-Receiver and “4” for X-Receiver.


The information above is for ArduCopter 3.3. Prior to AC3.2 the values are 2 for D-Receiver and 3 for X-Receiver.


SERIAL2_BAUD and SERIAL1_BAUD are not necessary for FrSky telemetry - it is a static value for D-Port (9600) and S-port (57600).


Transmitter set-up

Please refer to the OpenTX manual for how to control which values from the telemetry feed will be displayed on the transmitter’s screen.


If upgrading to OpenTx 2.1 you will need to replace your OpenTx 2.0 configuration and “discover” your sensors. There are other minor “oddities” - for example T1 (flight mode) and Tt2 (number of sats) are both called TEMP (switching mode helps you identify which is which).


Protocol information

This section outlines what values are being sent over the telemetry link, and how they are encoded.


The list below is produced by code observation, and is not fully complete.

Taranis telemetry screen identifier FRSKY_ID\_ Description
T1 TEMP1 send control_mode as Temperature 1 (TEMP1)
T2 TEMP2 send number of GPS satellites and GPS status. For example: 73 means 7 satellite and 3D lock
FUEL FUEL Send battery remaining
Vfas VFAS Send battery voltage
CURR CURRENT Send current consumption
Hdg GPS_COURS_BP Send heading in degrees based on AHRS and not GPS
GPS lat/long ? Is transmitted normally
Alt FRSKY_ID_BARO_ALT_BP/AP Barometer altitude

Other available values:

Taranis telemetry screen identifier FRSKY_ID\_ Description
RSSI Transmitter data
Batt, time Consumption (maybe mAh used?)
A1 Receiver voltage (not very useful since is always around 4-5V).


Taranis telemetry screen identifier FRSKY_ID\_ Description
GPS date&time Note: These were logged as some fixed date&time in the year 2000 on my Taranis SD card. Reviewing if this is a logging issue or a telemetry issue.
Air speed
Vertical speed

Hardware solutions

This section contains hardware-only MAVLink to FrSky converter solutions.

Please feel free to add your own solutions (or ask us to).