4.3.1 LEDs

There are 13 (10 yellow and 1 RGB) LEDs available on each of the QT1 Xplained Pro extension boards that can be used to visualize the behavior of the touch sensors. Each sensor has it's own set of LEDs. The slider has eight yellow LEDs, the buttons have one yellow LED each, and the wheel has a RGB LED. All LED's on the boards are active low, which mean that the microcontroller need to sink the corresponding IO lines to activate the LEDs.