Clocks; Lse Clock; Hse Clock; Reset Sources - ST STM32MP157 Series User Manual

6.2

Clocks

Two clocks are available on STM32MP157x-EV1 for STM32MP157xAA3 target microcontroller.
6.2.1

LSE clock

• External 32.768 KHz crystal
6.2.2

HSE clock

• External 24 MHz crystal
6.3

Reset sources

The reset signal of the STM32MP157x-EV1 platform is active low.
Sources of the platform reset are:
• Two reset buttons MB1263/B1 and MB1262/B2 (BLACK buttons)
• STM32MP157xAA3: internal voltage monitor, SW request or Watchdog
• STPMIC
• JTAG/SWD connector MB1262/CN14
• ETM Trace Mictor-38 connector MB1262/U10
• Embedded ST-LINK/V2-1
The STM32MP157xAA3 also drives a sub system reset, SUB_NRST signal on PD10 IO, to the peripherals: USB
Host Hub, MFX, Ethernet, and RGB_LTDC connector.
6.4

User buttons and LEDs

The Table 7 describes the HW configuration for the user buttons and LEDs
IO
PD8
PD9
PA13
PA14
6.5

Physical input devices: buttons

The STM32MP157x-EV1 board provides a number of input devices for physical human control.
These are:
• Two Reset buttons (MB1263/B1 and MB1262/B2)
• Four-way joystick controller with select key (MB1262/B1)
• Wake-up button (MB1263/B4)
Wakeup button (MB1263/B4)
Reset buttons (MB1263/B1 or MB1262/B2)
JOY_CENTER: Joystick select key (MB1262/B1 pin2)
JOY_DOWN: Joystick down direction (MB1262/B1 pin3)
JOY_LEFT: Joystick left direction (MB1262/B1 pin1)
UM2535 - Rev 1
Table 7. HW configuration for the user buttons and LEDs
LED color and label
PD8 is connected to the ORANGE LD4. Active High
PD9 is connected to the BLUE LD5. Active High
PA13 is connected to RED LD2. Active Low
MFX_IO13 is connected to ORANGE LED LD7. Active Low
Table 8.
Devices
Physical user devices: buttons
Awakes the platform from low-power modes.
Connected to STPMIC1A PONKEY, which
generates a wake-up signal on STM32MP1 PA0
NRST signal
MFX_IO0
MFX_IO1
MFX_IO2
UM2535
Clocks
Button label
-
-
User PA13
User PA14
Purpose/IO
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