Last edited 3 weeks ago

STM32MP257x-DKx - hardware description

Applicable for STM32MP25x lines

STM32MP257F-DK.png This article provides an overview of STM32MP257x-DK Discovery kits.

1. Article purpose[edit | edit source]

This article briefly describes:

  • How to assemble together the different elements provided in the commercial box and additional optional accessories
  • What are the different components present on the boards
  • How to connect the boards to external material
  • How to configure the board for boot
  • What are the configurations of the connectors pins

This article is valid for the STM32MP257F-DK More info green.png Discovery kit: the part numbers are specified in the STM32MP25 microprocessor part numbers article.

Info white.png Information
This article is only an introduction to the STM32MP257x-DK Discovery kit. Detailed information can be found in the STM32MP257x-DK Discovery kits user manuals.

2. Board assembly[edit | edit source]

The STM32MP257x-DKx Discovery kits package (STM32MP257F-DK More info green.png) contains the items listed below.

Position Description
1 MB1605 motherboard
2 microSD card


STM32MP257x-DKx Discovery kit out of the box
STM32MP257F-DK Discovery kit shown here (picture not contractual)
Info white.png Information
To complete the basic setup, you can buy an LVDS display and a CSI camera

The complete set will be then:

STM32MP257F-DK and additional accessories kits shown here (picture is not contractual)
Position Description
1 MB1605 main board
2 MicroSD card
3 LVDS display cable (provided via B-LVDS7-WSVGA package) - optional
4 7” LVDS WSVGA display with touch panel EDT ETML0700Z9NDHA panel provided via B-LVDS7-WSVGA package - optional
5 camera board FFC (provided via B-CAMS-IMX package) - optional
6 MB1854 board AI camera provided via B-CAMS-IMX package - optional


STM32MP257x-DK Discovery kit assembly
STM32MP257F-DK shown here (picture is not contractual)


2.1. How to connect LVDS display to ST board - optional[edit | edit source]

Display board assembly (picture is not contractual)


  • Check the above cable orientation thanks to the black mark and the white twisted pairs.
  • Find the LVDS port on STM32MP257x-DK Discovery kit (CN2) and the one on the display (CN1). One cable is provided in the LVDS display box.
  • On each port, insert the cable as described:
Display board assembly (picture is not contractual)


2.2. How to connect MB1854 camera board to ST board - optional[edit | edit source]

Camera board assembly (picture is not contractual)


  • Find the camera port on STM32MP257x-DK Discovery kit (CN8) (1 - in picture above) and the one on MB1854 (CN1) (2 - in picture above). One FFC is provided in the camera box.


  • On each port, carefully:
    • lightly pull the black plastic (1 - in picture below) to insert the contact side of the FFC towards the board (2 - in picture below).
    • Push the black plastic to hold the FFC (3 - in picture below).
Camera board assembly (picture is not contractual)


2.3. STM32MP257x-DK Discovery kit assembled[edit | edit source]


STM32MP257x-DK Discovery kit assembled
STM32MP257F-DK shown here (picture is not contractual)



3. Board overview[edit | edit source]

Main board MB1605, revision C-01: part of the STM32MP257x-DK Discovery kit More info green.png.

STM32MP257x-DK Discovery kit front side
STM32MP257F-DK shown here (picture is not contractual)


Details about some LEDs:

  • The LD11: turns green if power connection established (the power cable is inserted into the CN21 connector).
  • Two general-purpose color LEDs (LED1 and LD9) are available as light indicators:
    • The blue LED (LED1) is used as the Linux® Heartbeat LED, which is blinking as long as Linux® is alive on the Cortex®-A.
    • The orange LED (LD9) is used as a STM32Cube example verdict LED.
  • The two LEDs, the LD7 (red) and LD8 (green) are either connected to the STM32MP257 MPU ??? sentence coming form UM, not enough clear
  • The LEDs (LD5 and LD6) are used as ST-LINK indicator status.


STM32MP257x-DK Discovery kit back side
STM32MP257F-DK shown here (picture is not contractual)




4. Board connection[edit | edit source]

The connections shown in the picture below are the ones recommended to start with the STM32MP257x-DK Discovery kits. As shown in the board overview, other connectors are available for this board (for example GPIO expansion connector).


MB1605 motherboard: STM32MP257F 14x14MicroSD card slot, on back side2 x USB type A (host) → E.g. mouse  Keyboard  USB driver...USB2.0 DRD TypeC  →   flashing via STM32CubeProgrammerReset buttonEthernet → NetworkUSB Power Delivery TypeC → Power or  STLINKHDMI→ TV ScreenCSI camera connectorLVDS display connector
STM32MP257x-DKx Discovery kit connections (picture is not contractual)


5. Boot switches[edit | edit source]

The STM32MP257x-DK Discovery kit can boot from different Flash devices (microSD, eMMC); using the microSD card is recommended.

Boot 3 Boot 2 Boot 1 Boot 0 Boot mode Cortex-A35
0 0 0 0 Forced USB boot for flash programming
0 0 0 1 microSD card on SDMMC1
0 0 1 0 eMMC on SDMMC2
0 0 1 1 Development boot

'1' is considered when switch is pushed in "ON" position and is ‘0’ otherwise.



The boot related switches (SW1 and SW2 on the board overview picture) must be configured as illustrated by one of the following pictures:

Forced USB boot for flash programming
Boot from microSD card
Boot from eMMC
Development mode


6. GPIO mapping[edit | edit source]

6.1. GPIO expansion connector[edit | edit source]

The pins of the GPIO expansion connector (CN5 on the board overview picture) are described in the following table:

GPIO expansion connector
Function STM32 pin Pin Pin STM32 pin Function
3V3 - 1 2 - 5V
GPIO2 / I2C8_SDA PZ3 3 4 - 5V
GPIO3 / I2C8_SDL PZ4 5 6 - GND
GPIO4 / MCO1 PF11 7 8 PF13 GPIO14 / USART6_TX
GND - 9 10 PF14 GPIO15 / USART6_RX
GPIO17 / USART6_RTS PG5 11 12 PD2 GPIO18 / SAI2_SCKA
GPIO27 PZ9 13 14 - GND
GPIO22 PZ0 15 16 PZ1 GPIO23
3V3 - 17 18 PZ6 GPIO24
GPIO10 / SPI6_MOSI PC7 19 20 - GND
GPIO9 / SPI6_MISO PC4 21 22 PZ7 GPIO25
GPIO11 / SPI6_SCK PF7 23 24 PF4 GPIO8 / SPI6_NSS
GND - 25 26 PZ5 GPIO7
I2C2_SDA PF0 27 28 PF2 I2C2_SCL
GPIO5 / TIM8_CH4 PC10 29 30 - GND
GPIO6 / TIM5_CH1 PH8 31 32 PA5 GPIO12 / TIM2_CH4
GPIO13 / TIM4_CH2 PA1 33 34 - GND
GPIO19 / SAI4_FSA PD0 35 36 PF15 GPIO16 / USART6_CTS
GPIO26 PZ8 37 38 PD1 GPIO20 / SAI4_SDA
GND - 39 40 PB5 GPIO21 / SAI4_SDB

6.2. User buttons and LEDs[edit | edit source]

The GPIO assignments for the user buttons and LEDs are described in the following tables. Refer to LEDs and buttons on STM32 MPU boards article to get information on the functional mapping for each one.

GPIO for LEDs
LED color and label GPIO
Green LD8 PH5
Red LD7 PH4
Orange LD9 PH6
Blue LED1 PH7
GPIO for user buttons
Button GPIO
USER1 PC5
USER2 PC11

7. References[edit | edit source]