Hse: Osc 8 Mhz Clock Supply; Reset Sources - ST STM32 Nucleo-64 User Manual

Hardware layout and configuration
6.7.2

HSE: OSC 8 MHz clock supply

There are four ways to configure the pins corresponding to the external high-speed clock
(HSE):
•
HSE not used (default): PF0 and PF1 are used as GPIOs instead of as clock. The
configuration must be:
–
–
–
•
MCO from ST-LINK: MCO output of ST-LINK is used as input clock. This frequency
cannot be changed, it is fixed at 8 MHz and connected to the PF0-OSC_IN of STM32
microcontroller. The configuration must be:
–
–
–
•
HSE on-board oscillator from X3 crystal (not provided): for typical frequencies and its
capacitors and resistors, refer to the STM32 microcontroller datasheet and to the
Oscillator design guide for STM8S, STM8A and STM32 microcontrollers Application
note (AN2867) for the oscillator design guide. The X3 crystal has the following
characteristics: 8 MHz, 8 pF, 20 ppm. It is recommended to use NX3225GD-8.000M-
EXS00A-CG04874 manufactured by NIHON DEMPA KOGYO CO., LTD. The
configuration must be:
–
–
–
–
•
Oscillator from external PF0: from an external oscillator through the pin 29 of the CN7
connector. The configuration must be:
–
–
–
6.8

Reset sources

The reset signal of the STM32 NUCLEO-G070RB or NUCLEO-G071RB board is active low
and the reset sources include:
•
Reset button B2
•
Embedded ST-LINK/V2-1
•
Arduino Uno V3 connector from CN6 pin 3
•
ST morpho connector CN7 pin 14
22/44
SB25 and SB27 ON
SB17 (MCO) OFF
R33 and R34 OFF
SB17 ON
SB25 and SB27 OFF
R33 and R34 OFF
SB25 and SB27 OFF
R33 and R34 soldered
C24 and C25 soldered with 10 pF capacitors
SB17 OFF
SB25 ON
SB17 OFF
R33 and R34 removed
UM2324 Rev 2
UM2324