ST Nucleo G474RE

Overview

The Nucleo G474RE board features an ARM Cortex-M4 based STM32G474RE MCU with a wide range of connectivity support and configurations. Here are some highlights of the Nucleo G474RE board:

• STM32 microcontroller in LQFP64 package

• Arduino Uno V3 connectivity

• On-board ST-LINK/V3E debugger/programmer with SWD connector

• Flexible board power supply:

  • USB VBUS or external source(3.3V, 5V, 7 - 12V)

  • Power management access point

• Three LEDs: USB communication (LD1), power LED (LD3), user LED (LD2)

• Two push-buttons: RESET and USER

More information about the board can be found at the Nucleo G474RE website.

Hardware

The STM32G474RE SoC provides the following hardware IPs:

• Ultra-low-power with FlexPowerControl (down to 28 nA Standby mode and 84 µA/MHz run mode)

• Core: ARM® 32-bit Cortex® -M4 CPU with FPU, frequency up to 170 MHz

• Clock Sources:

  • 4 to 48 MHz crystal oscillator (HSE)

  • 32 kHz crystal oscillator for RTC (LSE)

  • Internal 16 MHz factory-trimmed RC ( ±1%)

  • Internal low-power 32 kHz RC ( ±5%)

  • 2 PLLs for system clock, USB, audio, ADC

• RTC with HW calendar, alarms and calibration

• 14x timers:

  • 1x 32-bit timer and 2x 16-bit timers with up to four IC/OC/PWM or pulse counter and quadrature (incremental) encoder input

  • 2x 16-bit 8-channel advanced motor control timers, with up to 8x PWM channels, dead time generation and emergency stop

  • 1x 16-bit timer with 2x IC/OCs, one OCN/PWM, dead time generation and emergency stop

  • 2x 16-bit timers with IC/OC/OCN/PWM, dead time generation and emergency stop

  • 2x watchdog timers (independent, window)

  • 2x 16-bit basic timers

  • SysTick timer

  • 1x low-power timer

• Up to 86 fast I/Os, most 5 V-tolerant

• Memories

  • Up to 128 KB single bank Flash, proprietary code readout protection

  • Up to 22 KB of SRAM including 16 KB with hardware parity check

• Rich analog peripherals (independent supply)

  • 2x 12-bit ADC 5 MSPS, up to 16-bit with hardware oversampling, 200 µA/MSPS

  • 4x 12-bit DAC, low-power sample and hold

  • 3x operational amplifiers with built-in PGA

  • 4x ultra-fast rail-to-rail analog comparators

• 16x communication interfaces

  • 1 x FDCAN controller supporting flexible data rate

  • 3x I2C FM+(1 Mbit/s), SMBus/PMBus

  • 4x USARTs (ISO 7816, LIN, IrDA, modem)

  • 1x LPUART

  • 3x SPIs (2x with multiplexed half duplex I2S interface)

  • 1x SAI (serial audio interface)

  • USB 2.0 full-speed interface with LPM and BCD support

  • IRTIM (Infrared interface)

  • USB Type-C™ /USB power delivery controller (UCPD)

• 12-channel DMA controller

• True random number generator (RNG)

• CRC calculation unit, 96-bit unique ID

• Development support: serial wire debug (SWD), JTAG, Embedded Trace Macrocell*

More information about STM32G474RE can be found here:

• STM32G474RE on www.st.com

• STM32G4 reference manual

Supported Features

The Zephyr nucleo_g474re board configuration supports the following hardware features:

Interface	Controller	Driver/Component
NVIC	on-chip	nested vector interrupt controller
UART	on-chip	serial port-polling; serial port-interrupt
PINMUX	on-chip	pinmux
GPIO	on-chip	gpio
I2C	on-chip	i2c
WATCHDOG	on-chip	independent watchdog
PWM	on-chip	pwm
ADC	on-chip	adc
DAC	on-chip	DAC Controller
FLASH	on-chip	flash memory
COUNTER	on-chip	rtc
SPI	on-chip	spi
die-temp	on-chip	die temperature sensor
FDCAN1	on-chip	CAN controller
RTC	on-chip	rtc

Other hardware features are not yet supported on this Zephyr port.

The default configuration can be found in the defconfig file: boards/st/nucleo_g474re/nucleo_g474re_defconfig

Connections and IOs

Nucleo G474RE Board has 6 GPIO controllers. These controllers are responsible for pin muxing, input/output, pull-up, etc.

For more details please refer to STM32G4 Nucleo-64 board User Manual.

Default Zephyr Peripheral Mapping:

• UART_1_TX : PC4

• UART_1_RX : PC5

• LPUART_1_TX : PA2

• LPUART_1_RX : PA3

• I2C_1_SCL : PB8

• I2C_1_SDA : PB9

• SPI_1_NSS : PB6

• SPI_1_SCK : PA5

• SPI_1_MISO : PA6

• SPI_1_MOSI : PA7

• SPI_2_NSS : PB12

• SPI_2_SCK : PB13

• SPI_2_MISO : PB14

• SPI_2_MOSI : PB15

• SPI_3_NSS : PA15

• SPI_3_SCK : PC10

• SPI_3_MISO : PC11

• SPI_3_MOSI : PC12

• PWM_2_CH1 : PA5 (might conflict with SPI1)

• PWM_3_CH1 : PB4

• USER_PB : PC13

• LD2 : PA5

• ADC1_IN1 : PA0

• DAC1_OUT1 : PA4

• FDCAN1_RX: PA11

• FDCAN1_TX: PA12

System Clock

Nucleo G474RE System Clock could be driven by internal or external oscillator, as well as main PLL clock. By default System clock is driven by PLL clock at 150MHz, driven by 16MHz high speed internal oscillator. The clock can be boosted to 170MHz if boost mode is selected.

Serial Port

Nucleo G474RE board has 3 U(S)ARTs. The Zephyr console output is assigned to LPUART1. Default settings are 115200 8N1.

Please note that LPUART1 baudrate is limited to 9600 if the MCU is clocked by LSE (32.768 kHz) in low power mode.

Programming and Debugging

Nucleo G474RE board includes an ST-LINK/V3E embedded debug tool interface.

Applications for the nucleo_g474re board configuration can be built and flashed in the usual way (see Building an Application and Run an Application for more details).

Flashing

The board is configured to be flashed using west STM32CubeProgrammer runner, so its installation is required.

Alternatively, OpenOCD or pyOCD can also be used to flash the board using the --runner (or -r) option:

$ west flash --runner openocd
$ west flash --runner pyocd

Flashing an application to Nucleo G474RE

Connect the Nucleo G474RE to your host computer using the USB port, then run a serial host program to connect with your Nucleo board.

$ minicom -D /dev/ttyACM0

Now build and flash an application. Here is an example for Hello World.

# From the root of the zephyr repository
west build -b nucleo_g474re samples/hello_world
west flash

You should see the following message on the console:

$ Hello World! arm

Debugging

You can debug an application in the usual way. Here is an example for the Hello World application.

# From the root of the zephyr repository
west build -b nucleo_g474re samples/hello_world
west debug