We are happy to bring you this release candidate of OpenTX 2.2.2, with support for the FrSky X-Lite radio!

We expect this to be the last of the 2.2 series, with the exception of any serious issues being discovered after release.

PLEASE NOTE the following important information before hastily jumping on it: Please back up your models and settings before upgrading so that you can go back to your previous version should you not like 2.2.2 or find issues that make it unsuitable for you. Use the “backup radio to file” companion feature for this to have an exact copy of what was on your radio.

  • This is pre-release software. We’ve done our best to ensure its quality but we still expect there may be issues, as is the purpose of a release candidate we need your feedback to report things we may have missed.

  • The manual has not yet updated to include all Horus documentation/OpenTX 2.2 changes, so get yourself a good coffee to wake up, and refer to the great communities for help e.g. openrcforums here, RCGroups and threads like this one. You can pop in our chat room where other users and/or devs may be available.

  • Check during companion install that it installs itself in the correct directory, usually you want “Companion 2.2”. If you used 2.2.0 release candidates a bug may cause it to install itself in “Companion 2.1”, potentially overwriting your 2.1 install.

  • SD card contents can be found here. Download the correct archive for your radio type, extract it to the root of an empty SD card and you’ll have all needed files. Please note that some existing OpenTX sound packs that where designed for 2.1 won’t work due to changes in the naming strategy, so you’ll likely want to use those that are included in this archive until popular 3rd-party packs are adapted.

  • OpenTX does not touch the internal flash of production Horus radios. Its contents do not need to be backed up and are not accessible in any way when OpenTX firmware is loaded.

  • Due to changes introduces by Horus, image, sound, and script file names for ALL radio are restricted to 6 characters in most places.


  • By default, the setting for companion is to download release only firmware, you NEED to go to settings/settings/application settings and set it to “Use releases and release candidates (testing)” to get new radio firmware or simply 2.2.2 RC firmware.

  • Companion now offers assistance for model conversion from one radio type to another. The transferred models NEED to be completely checked and validated before being used, as some things like switches assignments may not get converted properly. The proper way to transfer models from one radio to the other is: Select a profile for the destination radio, read the settings from the destination radio, open the source file or read the source radio, drag models onto the destination radio’s window, write destination radio.

  • The first versions of Frsky X10/X10s misuse the USB-C port for charging its internal battery. Do not plug anything else in there. For more details see here: FAQ for X10/X10s USB-C port

Known issues:

  • If you get an “Invalid Language” error when trying to download firmware after upgrading from 2.1 open the profile settings and reselect your radio type, even if it is already correct.
  • The progress bar in companion when reading firmware from a Horus is broken and will reach 100% at only 25% progress. Just wait, the window will close when the process is finished.

  • Horus X12S production version and beta version use different hardware. Companion defaults to production hardware, for beta radios check the “pcbdev” firmware option in the profile settings.

Download and install Companion and use it to retrieve and transfer the latest OpenTX firmware to your radio after configuring the proper radio type.

MUST READ : Xlite : Xlite

Xlite uses a ‘+’ pad for trims. One set of trims can be accessed directly with the ‘+’, the second set needs ‘+’ and pushing ‘shift’ at the same time. Depending on your radio mode, this can be convenient or not at all. We have introduced a solution that enable Aileron and Elevator of your actual radio mode to be always the default ‘+’ usage. Unfortunately, the firmware that FrSky included in their first batch of Xlite does NOT include this feature, so this is a fairly big usage difference between shipped firmware and actual OpenTx 2.2.2.

It is highly recommended to update xlite shipped version to this version or a later opentx version.

MUST READ : HORUS : Horus bootloader

Thanks to the work by Raphael Coeffic and Arne Schwabe, a bootloader is now availble for Horus. It allows you to flash a Horus firmware much faster by using the bootloader. There are now 3 methods for flashing OpenTX:

  • by turning on your radio in bootloader mode (by first holding T4 and T1 toward the center, then pressing the power button), connect to USB and then flash with Companion
  • by putting the firmware on the SD card, then start bootloader mode (by first holding T4 and T1 toward the center, then pressing the power button), select write firmwware, navigate to it and press ENTER
  • by connecting the HORUS to usb in the off state and use dfu-util (through Companion) like before


FrSky has released a new firmware version (180428) for R9M-EU modules, that is NOT compatible with previous OpenTx versions. OpenTX version 2.2.1 : only firmware up to 180329 are ok OpenTX version 2.2.2 : only firmware 180428 or later are ok

Main changes since 2.2.2RC3

  • small stability fixes
  • we expect this RC4 to be the same as, or very close to, the 2.2.2 release, so we encourage wide testing of it!

RC3 release notes

RC2 release notes

Main changes since 2.2.1

  • All Radio : fix setFailsafe special function (was overwriting GV0)
  • FrSky Xlite : support for the new radio
  • FrSky Horus : both modules are now turned off on model changes
  • FrSky Horus : add bootloader to Horus (see above)
  • FrSky Horus : allow splash image on Horus start (put image as /IMAGES/splash.png)
  • FrSky Horus : improve rotary encoder overall response
  • FrSky Horus : add glider support to model wizard
  • FrSky Horus : fix Timer display widget (do not display timer number if a name is defined)
  • FrSky Horus : display first persistent timer in model select screen
  • FrSky Horus : add mixer warning feature
  • FrSky Horus : rework backlight (mode OFF : screen nevers turn completely off, it goes to min backlight (5 for x12, 45 for x10), mode keys/controls : if off setting is set to absolute min, then screen goes fully dark)
  • FrSky Horus : fix T5 & T6 trim reuse
  • FrSky Horus : add receiver ID check feature
  • FrSky Horus : add more language support to Horus fonts
  • FrSky Horus : relaod all models on USB disconnect
  • FrSky X10 : mute audio when no audio is played
  • FrSky X9E : fix center beeps for LS -FrSky X9E : fix crossfire scripts for X9E navigation
  • FrSky X9E : review BT ui
  • FrSky X9 : rename trainer Master/Battery to Master/Serial
  • FrSky X7/X7S : add CPPM and SBUS trainer mode
  • FrSky X7/X7S : fix custom scripts output display
  • FrSky X7/X7S : add PREC and unit GVAR support
  • FrSky X7/X7S : fix R9M power cannot be changed
  • FrSky X7/X9 : fix display for timers over 99 hours
  • FrSky X7 : fix PPM center display
  • FrSky X7 : switch warning UI has been improved
  • FrSky Xlite/X7/X10 : fix a freeze when volume was set to 0 while bgmusic was playing
  • FrSky Xlite/X7/X10 : improve PWM reading latency with PWM stick are used
  • FrSky Xlite/X7/X10 : display stick type in analog screen
  • FrSky radios : display model notes before modules are activated (allow display of comments like ‘add external antenna’ before emission starts)
  • FrSky radios : add capability to set all custom failsafe channels at once
  • FrSky radios : improve R9M UI support
  • FrSky radios : fix broken UUID display
  • FrSky : telemetry support for new devices : Dual SBEC & High Power ESC (FrESC32_80A) and Gas Suite sensors
  • FrSky S6R : fix for LUA script when S6R do not show Quick Mode on last receiver firmware
  • FrSky S8R : fix for LUA calibration script showing wrong values on last receiver firmware
  • FrSky R9M : see notice above
  • All radios : fix GPS logs for small negative values
  • All radios : fix throttle warning for reverse POTS/SLIDERS too
  • All radios : allow the display of RAS on capable 128x64 radios
  • All radios : fix center trim beeps when cross trimming
  • All radios : apply THR trim feature also when cross trimming
  • All radios : Review FAI modes : now disables all telemetry sensors except RSSI and RXBT (also works with Crossfire)
  • All radios : backlight is forced ‘on’ for splaash and switch warning screens
  • All radios : individual trims that are disabled in FM settings are no longer visible on main view
  • All radios : don’t reinitialise last flight mode on flight reset
  • All radio : fix possible timer mode overflow
  • All radio : do not show hidden files on SDCard
  • ARM 9x : remove ‘nofp’ option which was conflicting with too many things
  • LUA : add getRtcTime() function
  • LUA : add getTxGPS() function for radio with internal GPS
  • LUA : add gtimer support (read using getGeneralSettings(), clear using resetGlobalTimer())
  • Crossfire : add support for text sensors like Flight mode
  • Crossfire : improve python crossfire parser to handle GPS data
  • Crossfire : fix X9E wheel navigation
  • Companion : do not display RC99 for ‘release’ version of firmwares
  • Companion : custom functions sound playblack fix
  • Companion : radio conversion improvements #5534
  • Companion : adjust source value ranges and editors in LS/CF/Telemetry #5437
  • Companion : fix new LS not available until model editor is reopened, and other minor editor propagation issues
  • Companion : small fixes and improvements to Inputs and Mixes editors #5942 #5029 #5957
  • Companion : log viewer Google Earth export fixes #5937
  • Companion : improve model print and compare #5568 #5645 #5866
  • Companion : add context menu to Outputs editor #5665
  • Companion : curve editor enhancements #5947
  • Companion : wizard now use mixer instead of override for throttle cut
  • Companion : ignore hidden files on SD sync
  • Companion : fix RF Output Power setting getting reset
  • Companion : fix disappearing mixer lines after an invalid line is removed
  • Companion : prevent crash on X9E simu when interacting with BT settings
  • Companion : Improve French and German translations
  • Simulator : telemetry widget now remembers last used log folder
  • Simulator : add mixer outputs to Radio Outputs widget #5811

Download links:

SDCard content for 2.2.2 RC4

SDCard changes since 2.2.1 :

  • 128x64 Crossfire lua have been modified to also support xlite (thx DieHertz)
  • add missing German audio files
  • change french telemko audio file
  • fix russian audio files that had too long names
  • add support for FrSky Xlite radio
  • update SxR scripts to support latest receiver firmware
  • add glider wizard for Horus
  • review some Horus graphics (mask_iconback)

OpenTX Companion 2.2.2 RC4 - Windows Installer If you get an error about “api-ms-win-crt-runtime-I1-1-0.dll missing” install MS VC++ runtime.

OpenTX Companion 2.2.2 RC4 - Mac OS X Disk Image

OpenTX Companion 2.2.2 RC4 - Linux DEB Package 64-bit

OpenTX Companion 2.2.2 RC4 - Ubuntu PPA (i386 and amd64) m


06 July 2018