In order to activate flight modes and features in Betaflight you need to setup the switches in your radio first. I will show you how to do it in OpenTX which is the same system used in the Frsky Taranis X9D, QX7, Horus X10, X-Lite, and Flysky Nirvana.
How Many Switches Can You Setup?
I know there might be a lot of switches available on a radio transmitter, you might not be able to use all of them due to the limited channels. You have to choose which ones you want to use.
Because we use 4 channels for basic controls like Throttle, Yaw, Roll and Pitch, only the rest of the channels can be used for switches. These are called auxiliary channels or AUX channels. Each switch will take up a channel.
There are 8 channels in PPM, so you can have at most 4 AUX channels. For SBUS that’s 16 so you can have maximum 12 AUX channels.
How Many Switches Do You Need?
You really don’t need that many switches. I normally only use 2 to 3 switches at most on a mini quad because there really aren’t too many things I need to control.
For example, I need a switch to arm the quad, another one to activate the buzzer when we lose it in the bushes. Perhaps another one to switch to Angle or Horizon mode.
How To Setup Switches in OpenTX?
It doesn’t matter if you are using PPM, SBUS or FPort, the process should be the same. I will show you how to configure one switch as an example.
All you have to do is to configure Mixer.
Mixer is used to assign inputs or sources to the channels, so you can send it to the receiver (and flight controller).
The first 4 channels are already occupied by throttle, roll, pitch and yaw, so we will have to use the next available channel, which is CH5 (Channel 5).
Scroll down to CH5, press the Enter key, it will take you to another screen.
In here, enter a name in “Mix Name”, you can enter anything you want. In this example I will just call it “ARM”, because that’s what I am going to use it for – arming the quadcopter.
In “Source”, pick the switch you want to use, in this case, switch “SD”. You don’t have to go through the list to find it, if you flip the desired switch, OpenTX will automatically select it for you. Pretty convenient huh?
No need to change any other setting, just leave them at default.
Repeat the same for other switches you want to setup, in my case, I created 3 more switches for “Mode”, “Beeper”, and “Free” (my spare switch just in case). This is my usual setup, I normally only use 8 channels – because for SBUS, using 8 channels has less latency than using 16.
If you also decide to use 8 channels like me, you have to change “Channel Range” to “CH1-8” in order to take advantage of the reduced latency. If you want to use 16 channels, then select “CH1-16” there :)
Switch is configured successfully!
Double check that the switches are working. Check in the Betaflight Receiver tab that the AUX channels are responding correctly when you flip those switches, AUX 1 is CH5, AUX 2 is CH6 and so on…
If it is then you can move on to setting up Betaflight modes tab :)
- Sep 2018 – tutorial created
- Sep 2019 – updated (removed input setup, no need for switches)