1. Introduction[edit source]
The following paragraphs describe the functional mapping of the LEDs and buttons.
2. Description[edit source]
2.1. LEDs[edit source]
| LED color | Purpose |
|---|---|
| Green |
Can be used at runtime for Linux examples |
| Red |
Used to show Cortex-A boot information[1] |
| Blue | U-Boot entering / exit indication then Linux heartbeat, which blinks as long as Linux[2] is alive[1] on the Cortex-A |
| Orange | Used for STM32Cube[3] examples verdict, on STM32MP15. Free for user on STM32MP13. |
2.2. Buttons[edit source]
| Button label | Purpose |
|---|---|
| WAKE UP | Allows the platform to be woken from any low-power mode[4] |
| USER1 |
Used at boot time by U-Boot to enter USB programming mode with STM32CubeProgrammer. This avoids manipulation of the STM32 MPU ROM code overview#Boot device selection when a valid U-Boot image is already present in the board. Can be used at runtime for Linux examples or STM32Cube examples, on STM32MP15. |
| USER2 |
Used at boot time by U-Boot to enter Android Fastboot mode. Used at runtime for Linux, on STM32MP13. |
| TAMPER | Allows to generate an external tamper event. Only present on STM32MP13 board. |
3. On STM32MP13x lines 
[edit source]
On STM32MP135F-DK Discovery kit, the GPIO assignment is as follow:
- The green LED is on the IO expander pin GPB6
- The red LED and USER2 button are on the pin PA13
- The blue LED and USER1 button are on the pin PA14
- The orange LED is on the IO expander pin GPB7
4. On STM32MP15x lines [edit source]
You can refer to the respective board-hardware descriptions to determine to which GPIO each function is mapped:
- STM32MP157x-EV1 - hardware description for the Evaluation boards
- STM32MP157x-DKx - hardware description for the Discovery kits.
5. References[edit source]