How do you control the LED on VOXL and VOXL-Flight?
VOXL has a RGB LED, shown here, and can be set via code running on the apps processor:
VOXL Datasheet - LED
VOXL-Flight has a few RGB LEDs, 2 of them are controlled via PX4 (STM32), but the other one can be controlled via the apps_processor as well (labeled LED3 here):
VOXL-Flight Datasheet - LED3
To control this LED, you can follow instructions here: