Installing OpenTX Comp.



Well, you’re ready to flash OpenTX 2.x to your Taranis for the first time. Before we do that, we need to consider a few things.

There is currently a lot of confusion out there about this process. Do I have to use Companion in one form or another? (Yes, but only for the first flash.) Why can’t I just copy it to the SD card and flash it through Bootloader mode in the TX? (Because until you flash OpenTX, you don’t have a user accessible bootloader.) Where do I get OpenTX 2.x? (You don’t…you download OpenTX Companion, install it, and let OpenTX Companion find the new version for you, or you use your existing install of Companion9X.) Etc., etc., etc.,…….

We’ll tackle a few of those questions in this lesson, as well as show you how to flash your TX in two or three different ways. Hopefully, we can take some of the mystery out of it for you.

For a printable PDF of this course please click here: Installing OpenTX Companion

Lesson Goals

There are two goals for this lesson:

  1. Goal #1: Download and install OpenTX Companion
  2. Goal #2: Use OpenTX Companion to flash OpenTX v2.x to your Taranis transmitter


Here’s what you’ll need to know to get started:

  1. You’ll need to have a working copy of the STM32 BOOTLOADER installed.
  2. You’ll need to know how to download and save a program on your computer.
  3. You’ll need to know where your computer saves your downloaded programs before they’re installed.
  4. You’ll need to know how to install a downloaded program on your computer.


One real problem is that there are OpenTX users at all stages of this process, from raw newcomer to advanced super users. It would be far beyond the scope of this lesson to try and cover each situation individually. Instead, we’re going to assume (and, yes, I know what that means) that you are a brand new users, totally unfamiliar with the procedure, and without any software directly related to OpenTX installed on your computer other than the STM32 BOOTLOADER driver that you installed using Zadig. It’s vital that you can see that it’s installed in the Windows Device Driver when you have your TX OFF and plug it into your computer. If you don’t have that, you’re not going anywhere.

If you’re currently using OpenTX (either r2940 or v1.99.x) and have upgraded your firmware before, you can simply tell Companion 9X or OpenTX Companion to get and install the new v2.x firmware. I’ve been doing that for several months (current date: 06/2014), and it has worked flawlessly. But, then again, if you’ve done that, you probably wouldn’t be here. J

 Because getting your computer to talk to the Taranis and flashing for the first time are such problem areas, there are, literally, hundreds of forum posts on the process. By far one of the best that I’ve seen is by Cleon on Scott Page’s FrSky Taranis with OpenTX 2.0 and beyond forum, specifically Post #1452 at If what we do here doesn’t float your boat, check out Cleon’s post. In fact, you’d probably be smart to bookmark that forum as well as Wayne’s FrSky Taranis – 16 Channels, Full Telemetry, RSSI forum at: Both are treasure troves of help and should be in every OpenTX and Taranis user’s toolbox.">

Just to review, here are the givens at the start:

  1. You have an installed copy of the STM32 BOOTLOADER on your system.
  2. You are competent in downloading and installing applications from the Web.
  3. You do not have OpenTX Companion installed on your computer. If you have Companion 9X installed, that’s fine. OpenTX installs in its own folder, and the two live happily together without conflict. If you’re still using Companion 9X, now is probably the time to upgrade to OpenTX Companion. I still have C9X on my machine and use it to upgrade my older Turnigy 9X equipped with a FrSky module and running OpenTX r2490. It works just fine!

OK, we’re off!


Step #1: Checking the STM32 BOOTLOADER DO THIS!!

  1. Using the steps provided in the previous lesson, Using Zadig, plug your Taranis into your computer with it OFF.
  2. Give Windows a few seconds to recognize the TX, then open the Device Driver and ensure that the STM32 BOOTLOADER device is loaded. You should see something like this:STM_complete
  3. Leave the Device Manager open, and fire up your browser.

Step #2: Downloading and Installing OpenTX Companion

NOTE: Version numbers have changed!  The numbers given in the images are out of date.  Use the latest versions for your work.
  1. Point your browser to the OpenTX Download Page: Downloads: Improving Your TX. If you haven’t already done so, bookmark or add this page to your bookmarks/favorites half a dozen times or so. It’s your official source for all things approved for Taranis. Note that there are resources here for working with Taranis audio, images that you can use on your Taranis and other downloads that may or may not interest you at the moment. The point is, don’t forget about this page!opentxDwnlds
  2. Choose the latest edition of OpenTX Companion and click it.
  3. Select the correct platform for your computer and click it.otxPlatform
  4. Windows will ask you what to do with the file. Click: “Save File” to authorize the download. Note that the file name is something similar to: campanionInstall_2.0.3.exe. If you can’t find where Windows puts it, you’ll need the file name to search for it.ctxdnld
  5. Your download time will vary, depending upon the speed of your Internet connection and your computer. On my machine, it takes between 10-15 seconds, and I’m running a Core I-4, 3.3GHz processor with a relatively slow (by some standards) 15MB DSL line.
  6. When the download is completed, use Windows Explorer to locate it. I can’t answer for everyone, but my download utility through Firefox is configured to save downloads in the “Downloads” folder. Your experience may vary. If you can’t find it, type the file name in the search bar. If you get it right, that should do it.OTXdwnld_folder_w
  7. Double-click the file to begin the install. You may see a screen asking you if you wish to allow the program to make changes to your computer. Select “Allow” to move onward.
  8. You’ll then see the standard window asking if you accept the Terms and Conditions. Since you can’t install the software unless you do, click, “Yes”.
  9. The next screen is the component selection screen. There’s only one option, so click “Next”.
  10. The next screen asks where you want your computer to put the program. Unless you have an overwhelming reason not to, accept the default by clicking “Next”.OTXlocation
  11. Finally, Setup asks you where you’d like to create the programs shortcuts. Again, unless you have an overwhelming reason not to, keep things simple by selecting the default (OpenTX Companion). Leave “Do not create shortcuts” at the bottom of the window unchecked to create the shortcuts we all love.OTXmenu_folder
  12. Click “Install” to start the installation. It takes less than 5 seconds on my machine, and the standard progress bar keeps me informed as to the progress. When you’re finished, you’ll see the screen below:OTXcomplete
  13. Click “Next”, and the “Finish” screen displays with the option to launch OpenTX selected. Click “Finish” to accept that option.
  14. Take time to look at the next lesson: Part 3: Flashing OpenTX BEFORE you proceed any farther. There are still things to do, and having an understanding of what they are and how they fit together helps to ensure success.

CONGRATULATIONS! You’ve just installed OpenTX Companion on your computer! Don’t you feel proud of yourself?



Installing OpenTX Comp. — 17 Comments

  1. SO I go to the link provided above and there is no option to download OpenTX Companion. I only see an option for the older Companion9X. Has something changed recently?

    I had an original Taranis and sold it because the porcess to upgrade to OpenTX seemed pretty complicated. I recenly purchased a Taranis Plus because it already comes with OpenTX installed and theoretically upgrades to firmware shouldn’t be as hard.

    Anyway, is OpenTX Companion available somewhere?

    • The link takes you to the official OpenTX download page. The top link, “OpenTX v2.1.0” will download both Companion and OpenTX. As of now (08/06), v2.1.1 has not been officially released.

      Give that a shot.

      Leonard (mac44mag)

  2. Well, I installed OpenTX 2.0.17 guidelines as above, but when I click on the program icon it does not run on Windows 7 (Windows hourglass appears for about 5 seconds and then nothing happens). What to do? The STM32 BOOTLOADER driver is installed and working …
    Thanks for your help!

  3. Gday Leonard,

    I have just purchased a Taranis Plus and very green to this. I am ensuring I have the STM32 BOOTLOADER in the Correct place on the Device Manager. It came up and I updaed the Device Driver, and now it is called “STM Device in DFU Mode” and is located in the USB Controllers section… is this right?

    Thanks in advance


  4. I think the improvements are very useful, not tested it till now, but they are necessary to get a logic running system.
    But I think the whole software updates run’s in a wrong direction. If someone want’s to sell devices with a open software to many people the most important thing is to have a complete software documentation (not the source code) from the newest software, but only the changes are documented. This is not very customer friendly. The most people have no time to check up 100d’s of sites. I know a lot of people selling their Taranis, because there are to less hints and no help boxes in the companion software.

    Yesterday I installed OpentTX 2.0.13 de (german) comp for TX Taranis. My last software version was companion9x 2940r. Everything is all right. But than i go to the preferences but there are 2 not documented points in the first preferences tab:
    (Everything is translated from the german version to english)

    1) Preferences tab (TX Profile) -> other preferences -> SD folder path………………open folder

    What is meant by that ? Have you to switch on the taranis and connect it to the usb port and than browse to the SD card on the TX taranis ???????

    2) Directly beneath the “SD folder path setting” there is a hint, that no preference profile is saved. Why there is no hint where you have to it ? You first have to load your TX preferences from the TX and in that window (its the window where your Models are shown) You have to choose the first point “TX fundamental preferecnes” (settings) and in this window you can save the preferences profile.

    So I need help refers to 1). Whats SD path folder, what to do ?

    Many thanks for the good software, but please give more helps and hints.

    (Programmer since 32 Years)

    • Hello, Kai!

      A) Yes, in order to view the SD card contents, you need to boot the Taranis in Bootloader mode by holding both of the horizontal trim switches in toward the center THEN pushing up on the power button. After that, connect the Taranis to your computer via a USB cord. On a Windows computer, you should then be able to view two new drives in Windows File Explorer: TARANIS and one other addition. The actual name and volume letter vary from computer to computer. DO NOT open or work with the TARANIS volume, as it contains all of your system firmware. The other removable volume is the SD card.

      B) We have nothing to do with the actual construction or compilation of the software. Any suggestions for changes or improvements should probably go through the developers. They read most of the forums regularly.

      Thank you for your comments.

      Leonard (mac44mag)

  5. Under the Windows files there was a BIN file that had an OpenTX icon. Apparently this is what I created my shortcut from. I deleted the shortcut and then opened the file from “C:\Program Files (x86)\companion.exe” as you stated and all is well.Even the new shortcut is working fine. Thanks for taking the time to help me.

  6. After installing OpenTX Companion and trying to open I get an “Invalid binary EEPROM file C:\opentx-taranis-en.bin” error. Just wondering if I did something wrong? Download ver 2.0.12. I’m really enjoying the course and any help will be greatly appreciated.

    • Wow! I’ve never seen that one before. You did download and install the new version from the OpenTX Download site, right?

      Perhaps you could give us a few more details? Perhaps you could tell me what you’re clicking to open Companion?

      Leonard (mac44mag)

        • I tried uninstalling and re downloaded with the same results. I even tried an earlier version. After I get the error and I close the window the program seems to open okay. I’m just worried that it may not work right.

          • Do you see OpenTX Companion in your program listings? In other words, can you open Companion from anywhere else but the shortcut? You might try recreating your shortcut by right-clicking on the companion.exe file and creating a shortcut to your desktop from there? Mine is located in: “C:\Program Files (x86)\OpenTX\companion.exe”. It sounds as if your shortcut may be trying to call either the wrong application and/or looking in the wrong place. I doubt it there’s anything serious wrong with either your computer or OpenTX Companion.

            Let me know. This one interests me.

            Leonard (mac44mag)

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