In this article, we will look more in-depth to the FrSky Taranis Software and the differences between OpenTX/FrOS and RF firmware. In one of our previous articles, we have seen the differences between the EU_LBT & Non-EU(FCC) firmware for FrSky products and how that affects your range etc.

What is a software? 

According to the actual definition of software, it is a collection of computer instructions or data that tell a machine or a computer on how it should work.

In our case software refers to both the OpenTX Companion software as well as the firmware on the Taranis called OpenTX/FrOS, where FrOS is basically FrSkys own software-firmware made in house for the Taranis series, but we usually flash OpenTX over the FrOS because of the added features and community support for it. 



OpenTX is an open-source firmware that has been designed to run on RC radio transmitters. This firmware comes with highly configurable settings and features that are more than what’s found on traditional radios. Since it is an open-source project, the feedback from the thousands of users from around the world gets baked into the upcoming releases with more stability and quality.

As mentioned, OpenTX is a firmware that runs on the processor in your Taranis (or other) radios. The reason why I mentioned processor is that radios have two firmware on it. One in the main processor where we flash OpenTX and the other in the internal RF module (XJT module).

For more references to the internal RF module and its firmware, please have a look at our previous article regarding EU & Non-EU firmware from HorusRC Blog.


OpenTX Companion

The OpenTX companion as the name implies is companion software that is run on your computer that is used to support the radio transmitter firmware. This includes flashing new updates, backing up settings and models, running simulators etc. It works on Windows, macOS and Linux distributions.

The OpenTX Companion is what allows you to flash your radio with OpenTX firmware. The companion software runs on your PC/Mac and gives you several options like updating your radio, backing up the models, flashing new splash screen ( the bootup logo that comes up when you turn on your radio), editing the settings of the radio like adding lua scripts etc.

The above image represents the OpenTX companion on the Windows platform. For more information on how to flash OpenTX on your Taranis Radios like FrSky Taranis QX7 or X9D or any other radios supporting OpenTX, check out the previous article from our HorusRC Blog


RF Module Firmware

We have discussed what firmware is for the radios processor but the processor is not the one transmitting the RF signal to the receiver, rather, the processor sends a command to another RF transmitter radio which then modulates the electrical signal into the Radio Frequency signal.

In the Taranis radios, you will have an internal 2.4GHz radio module(XJT module), similarly, you can use the JR bay on the back of the radio to connect external RF modules such as the FrSky R9M or Team Black Sheep CrossFire system or any other module of your liking. These modules talk to the radios the main processor and then transmit the received messages to your receiver wirelessly.

So these RF modules/radios also need firmware to know what to do. This firmware is made by the manufacturer of the module and not any independent developers like OpenTX.

It is quite important to keep matched firmware for the RF modules and the receivers for them to talk or connect to each other properly. If your RF module and your receivers have two different versions of the firmware, they won’t be able to bind together. Latest ACCESS protocol from FrSky allows Over-the-air updates for receivers which is amazing as now you are not required to manually push the button the receivers to get it to update.

To flash your RF module and receivers, you can copy-paste the firmware BIN file to the SD card of your Taranis and go to the settings to flash the RF module as well as the receivers.


In this article, we have seen what FrSky Taranis Software consists of and how it works. The main processor controls the functions of the radio controller and at the same time sends commands to the RF module for the channels data etc. Overall in a FrSky Taranis Software, one belongs to the Radio controller itself and the other firmware goes to the RF module and then OpenTX companion to flash the radio with the correct firmware.