A 9DOF MultiWii board communicates with a DFRobot v2 LED Ring via I2C protocol.
Blue LED = north direction deducted from the magnetometer
RED Leds = direction of inclination
Green Leds = FC board arming ON
flash white LEDs = stick setup acknowledgement (for LCD and ACC trims)
We could imagine many more functions or LED patterns in the future as every color of the 12 RGB LED can be reached individually with 64 brightness levels.
The LED Ring soft was fully rewritten for this need.