The APM 2.6 is a flight controller for drones which allows RC and autonomous flight. This is a Quick & Easy Manual on Flashing the APM 2.6 PPM encoder to allow Radio-Throttle FailSafe
Note: This process is not always necessary. Reasons include corrupted PPM encoder or old firmware on APM clone boards.
Context for flashing the PPM Encoder: The Radio-Throttle Failsafe function on the APM 2.6 works such that if the flight controller no longer receives a signal from the RC transmitter (via the onboard RC receiver) then a predetermined action occurs, for example: Return to launch, land, continue with mission, stop motors or do nothing.
In the event of a 'no pulse' situation the FailSafe is triggered, but only if the throttle (Channel 3) PWM value drops below a pre-set value, known as the 'FS PWM'.If, when the RC transmitter is switched off or loses contact with the receiver, there is no change in the throttle PWM value i.e. it does not drop below the pre-set FS PWM value, then FailSafe will not be initiated and you may need to flash the PPM Encoder (Atmega32U2) on the APM board. Reasons for this include: - To resolve a corrupted encoder. - To upgrade to a newer firmware version, - Because the board has an older firmware version unable to facilitate the Radio-Throttle 'no pulse' FailSafe response.