The STM32F4 DISCOVERY board has these LEDs:
- Green LED: PD12, active-high (LED emits light when PD12 is high)
- Orange LED: PD13, active-high (LED emits light when PD13 is high)
- Red LED: PD14, active-high (LED emits light when PD14 is high)
- Blue LED: PD15, active-high (LED emits light when PD15 is high)