Last edited 5 years ago

STM32MP157X-DKX - hardware description

This article provides an overview of STM32MP157x-DKx Discovery kits.

1. Article purpose[edit source]

This article briefly describes:

  • what are the different components present on the board
  • how to connect the board to external material
  • how to configure the board for boot
  • what are the configurations of the connector pins

This article is valid both for the STM32MP157A-DK1 and STM32MP157C-DK2 Discovery kits: the part numbers are specified in the STM32MP15 microprocessor part numbers article.

Warning white.png Warning
This article is only an introduction to the STM32MP157x-DKx Discovery kits. Detailed information can be found in the STM32MP157x-DKx discovery board user manual.

2. Board assembly[edit source]

The STM32MP157x-DKx Discovery kits packages (STM32MP157A-DK1 and STM32MP157C-DK2) are delivered assembled, and contain the items listed below. A USB Type-C cable is also included.

Please note that;

  • the STM32MP157A-DK1 Discovery kit neither includes the "WLAN + Bluetooth" component (muRata LBEE5KL1DX), nor the MB1407 daughterboard DSI display
  • the STM32MP157C-DK2 Discovery kit includes the "WLAN + Bluetooth" component (muRata LBEE5KL1DX), and the MB1407 daughterboard DSI display
Position Description
1 MB1272 motherboard ("WLAN + Bluetooth" component included only for the STM32MP157C-DK2 Discovery kit)
2 MB1407 daughterboard DSI display (480x800 pixels): only for the STM32MP157C-DK2 Discovery kit
3 microSD card


STM32MP157x-DKx Discovery kit assembled
STM32MP157C-DK2 shown here (picture not contractual)
(for the STM32MP157A-DK1, the element 2 is not present)


3. Board overview[edit source]

Position Description
1 MB1272 motherboard
2 MB1407 daughterboard DSI display (480x800 pixels): only for the STM32MP157C-DK2 Discovery kit
3 (CN15) microSD card
STM32MP157x-DKx Discovery kit front side (first angle)
STM32MP157C-DK2 shown here (picture is not contractual)
Position Description Position Description
10 (U5) DDR3L 16 bits 11 (CN5) 2 USB Type-A (host)
12 (U13) STM32MP157x 12x12 13 (U14) HDMI
14 (CN7 and U12) USB Type-C (DRP) 15 (CN8 and (U18) Ethernet
16 (B1) Wakeup button 17 (CN10) Audio headset
18 (U20) Audio codec (Cirrus CS42L51) 19 (B2) Reset button
20 (LD5) User LED (green)[LEDs 1] 21 (B3) User button (USER1)
22 (LD6) User LED (red)[LEDs 1] 23 (B4) User button (USER2)
24 (LD7) User LED (orange)[LEDs 1] 25 (LD8) User LED (blue)[LEDs 1]
26 (CN11 and U19) USB micro-B (ST-LINK/V2-1) 27 (LD4) ST-LINK/V2-1 LED (bicolor)[LEDs 2]
28 ('CN12) ST-LINK/V2-1 DFU 29 (CN9) HDMI connector


STM32MP157x-DKx Discovery kit front side (second angle)
STM32MP157C-DK2 shown here (picture is not contractual)
Position Description Position Description
10 (U5) DDR3L 16 bits 11 (CN5 and U7) 2 USB Type-A (host)
12 (U13) STM32MP157x 12x12 13 (U14) HDMI
14 (CN7 and U12) USB Type-C (DRP) 15 (CN8 and (U18) Ethernet
30 (LD1) USB Type-A LED (red)[LEDs 3] 31 (CN2) GPIO expansion
32 (U4) PMIC (STPMIC1A) 33 (CN4) DSI LCD connector
34 (LD3) Ethernet LED (green)[LEDs 4] 35 (CN6) USB Type-C (power 5V-3A)
36 (LD2) Power LED (green)[LEDs 5] 37 (U8) WLAN + Bluetooth (muRata LBEE5KL1DX): only for STM32MP157C-DK2 Discovery kit
40 (CN13) Arduino Uno connector (socket 10x1) 41 (CN14) Arduino Uno connector (socket 8x1)


STM32MP157x-DKx Discovery kit back side
STM32MP157C-DK2 shown here (picture is not contractual)
Position Description Position Description
40 (CN13) Arduino Uno connector (socket 10x1) 41 (CN14) Arduino Uno connector (socket 8x1)
42 (LD9) Arduino LED (green) 43 (SW1) Boot mode selection
44 (CN16) Arduino Uno connector (socket 8x1) 45 (CN17) Arduino Uno connector (socket 6x1)


Details about some LEDs:

  1. 1.0 1.1 1.2 1.3 LD5, LD6, LD7, LD8: some user LEDs are used to reflect the system activity, while the others are left free to be used by the application, as explained in LEDs and buttons on STM32 MPU boards article
  2. LD4: flashes red if ST-LINK/V2-1 connection not established, else green
  3. LD1: turns red if USB Type-A connection established
  4. LD3: flashes green when Ethernet connection established
  5. LD2: turns green if power connection established

4. Board connection[edit source]

The connections shown in the picture below are the ones recommended to start with the STM32MP157x_DKx Discovery kits. As shown in the board overview, other connectors are available for these boards (for example HDMI).


MB1272 motherboard: STM32MP157x 12x12,  PMIC,  DDR3MicroSD card slot2 x USB Type-A (host) → mouse,  keyboard or USB driver2 x USB Type-A (host) → mouse,  Keyboard or USB driverUSB micro-B (ST-LINK/V2-1) → PC virtual COM port and debugReset buttonEthernet → NetworkUSB Type-C (power 5V-3A)
STM32MP157x-DKx Discovery kit connections

STM32MP157C-DK2 shown here without the MB1407 daughterboard DSI display to avoid hiding the connections (picture is not contractual)


5. Boot related switches[edit source]

The following table defines the different combination of the boot mode selection switches:

Info white.png Information
"Boot 1" is grounded (always 0) on the Discovery kits
Boot modes
Boot mode Boot 0 Boot 1 Boot 2
Forced USB boot
for flashing
0 0 0
Not supported 1 0 0
Engineering boot 0 0 1
microSD card 1 0 1

Below the corresponding configurations of the boot related switches (SW1 on the board overview picture):

Forced USB boot for flashing
Engineering boot
Boot from microSD card

6. GPIO mapping[edit source]

6.1. GPIO expansion connector[edit source]

The pins of the GPIO expansion connector (CN2 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 / I2C5_SDA PA12 3 4 - 5V
GPIO3 / I2C5_SCL PA11 5 6 - GND
GPIO4 / MCO1 PA8 7 8 PB10 GPIO14 / USART3_TX
GND - 9 10 PB12 GPIO15 / USART3_RX
GPIO17 / USART3_RTS PG8 11 12 PI5 GPIO18 / SAI2_SCKA[EX 1]
GPIO27 / SDMMC3_D3 PD7 13 14 - GND
GPIO22 / SDMMC3_CK PG15 15 16 PF1 GPIO23 / SDMMC3_CMD
3V3 - 17 18 PF0 GPIO24 / SDMMC3_D0
GPIO10 / SPI5_MOSI PF9 19 20 - GND
GPIO9 / SPI5_MISO PF8 21 22 PF4 GPIO25 / SDMMC3_D1
GPIO11 / SPI5_SCK PF7 23 24 PF6 GPIO8 / SPI5_NSS
GND - 25 26 PF3 GPIO7
I2C1_SDA[EX 2] PF15 27 28 PD12 I2C1_SCL[EX 2]
GPIO5 / MCO2 PG2 29 30 - GND
GPIO6 / TIM5_CH2 PH11 31 32 PD13 GPIO12 / TIM4_CH2
GPIO13 / TIM3_CH2 PC7 33 34 - GND
GPIO19 / SAI2_FSA[EX 1] PI7 35 36 PB13 GPIO16 / USART3_CTS
GPIO26 / SDMMC3_D2 PF5 37 38 PI6 GPIO20 / SAI2_SDA[EX 1]
GND - 39 40 PF11 GPIO21 / SAI2_SDB[EX 1]
  1. 1.0 1.1 1.2 1.3 The SAI2 is shared between the audio codec and the GPIO expansion connector. By default, the SAI2 is connected to the audio codec thanks to Solder Bridge SB13, SB14, SB15, and SB16: more details in the STM32MP157x-DKx discovery board user manual.
  2. 2.0 2.1 Warning: the I2C1 is used to communicate with several on-board peripherals, but is also available on the GPIO expansion connector. So, it is important to ensure that new components added on the I2C1 connection will not disturb the bus behavior.

6.2. Arduino Uno connector[edit source]

The pins of the Arduino Uno connector are described in the following table:

Arduino Uno connector
Socket 10x1 (CN13)
Pin names Signal name STM32 pin Comment
1 ARD_D8 PG3 IO
2 ARD_D9 PH6 TIM12_CH1
3 ARD_D10 PE11 SPI4_NSS and TIM1_CH2
4 ARD_D11 PE14 SPI4_MOSI and TIM1_CH4
5 ARD_D12 PE13 SPI4_MISO
6 ARD_D13 PE12 SPI4_SCK
7 GND - GND
8 VREFP - VREF+
9 ARD_D14 PA12 I2C5_SDA
10 ARD_D15 PA11 I2C5_SCL
Socket 8x1 (CN14)
Pin names Signal name STM32 pin Comment
1 ARD_D0 PE7 UART7_RX
2 ARD_D1 PE8 UART7_TX
3 ARD_D2 PE1 IO
4 ARD_D3 PD14 TIM4_CH3
5 ARD_D4 PE10 IO
6 ARD_D5 PD15 TIM4_CH4
7 ARD_D6 PE9 TIM1_CH1
8 ARD_D7 PD1 IO
socket 8x1 (CN16)
Pin names Signal name STM32 pin Comment
1 NC - NC (reserved for test)
2 3V3 - IOREF 3V3
3 NRST NRST NRST
4 3V3 - 3V3
5 5V - 5V
6 GND - GND
7 GND - GND
8 VIN - Not connected
Socket 6x1 (CN17)
Pin names Signal name STM32 pin Comment
1 A0 PF14 ADC1_IN0
2 A1 PF13 ADC1_IN1
3 A2 ANA0 ADC1_IN6
4 A3 ANA1 ADC1_IN2
5 A4 PC3 / PA12 ADC1_IN13
6 A5 PF12 / PA11

6.3. User buttons and LEDs[edit source]

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

GPIO for user buttons and LEDs
LED color and label Button label GPIO
Green LD5 (*) USER1 (*) PA14
Red LD6 (*) USER2 (*) PA13
Orange LD7 - PH7
Blue LD8 - PD11
Warning white.png Warning
(*) Both a LED and a button are connected to the same GPIO, with inverted logic for the LED control (so the LED is switched on when the GPIO output is set to low).