Auxiliary Functions

This page describes how to set up additional features which can be invoked from the transmitter’s auxiliary function switch (normally channel 7).

Configuring which transmitter channel is used

By default the channel 7 is used but this can be changed to another channel by setting the AUX_CH parameter. For example, if you would prefer to use channel 9, set AUX_CH to “9”.

Assigning the Feature

The CH7_OPTION parameter controls which feature is assigned to the auxiliary switch. By default this is the “Save Waypoint” feature.

If using the Mission Planner, the Config/Tuning >> Basic Tuning’s “Ch7 Opt” drop-down can be used to easily set the desired feature.


Supported Features

CH7_OPTION Feature Description
0 Disabled No feature assigned
1 Save Waypoint The vehicle's position will be stored as a new waypoint in the mission command list. Use Auto mode later to return to this location
2 Learn Cruise Speed Record the vehicle's speed and throttle to the CRUISE_SPEED and CRUISE_THROTTLE parameters
3 Arm / Disarm Arm or Disarm the vehicle
4 Manual Change to Manual mode
5 Acro Change to Acro mode
6 Steering Change to Steering mode
7 Hold Change to Hold mode
8 Auto Change to Auto mode
9 RTL Change to RTL mode
10 SmartRTL Change to SmartRTL mode
11 Guided Change to Guided mode

Check the channel range


The configured feature will be triggered when the auxiliary switch’s pwm value becomes higher than 1800. It will be deactivated when the value falls below 1200.

You can check the pwm value sent from the transmitter when the switch is high and low using the Mission Planner’s Initial Setup >> Mandatory Hardware >> Radio Calibration screen. If it does not climb higher than 1800 or lower than 1200, it is best to adjust the servo end points in the transmitter.