Last edited 2 days ago

LEDs and buttons on STM32 MPU boards

Applicable for STM32MP13x lines, STM32MP15x lines, STM32MP25x lines

1. Introduction[edit | edit source]

The following paragraphs describe the functional mapping of the LEDs and buttons.

2. Description[edit | edit source]

2.1. LEDs[edit | 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][4] examples verdict, on STM32MP15 and STM32MP25. Free for user on STM32MP13.

2.2. Buttons[edit | edit source]

Button label Purpose
WAKE UP Allows the platform to be woken from any low-power mode[5]
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. Used at runtime for Linux on STM32MP25.

USER2
Used at boot time by U-Boot to enter Android Fastboot mode. Not yet supported on STM32MP25

Used at runtime for Linux, on STM32MP13.
Can be used at runtime for STM32Cube examples on STM32MP25.

TAMPER Allows to generate an external tamper event. Only present on STM32MP13 board and STM32MP25 board.

3. On STM32MP13x lines More info.png[edit | edit source]

You can refer to the STM32MP135x-DK - hardware description to determine to which GPIO each function is mapped.

4. On STM32MP15x lines More info.png[edit | edit source]

You can refer to the respective board hardware descriptions to determine to which GPIO each function is mapped:

5. On STM32MP25x lines More info.png[edit | edit source]

You can refer to the respective board hardware descriptions to determine to which GPIO each function is mapped:

6. References[edit | edit source]