.. zephyr:board:: stm32l476g_disco

Overview

The STM32L476G Discovery board features an ARM Cortex-M4 based STM32L476VG MCU with a wide range of connectivity support and configurations. Here are some highlights of the STM32L476G Discovery board:

STM32L476VGT6 microcontroller featuring 1 Mbyte of Flash memory, 128 Kbytes of RAM in LQFP100 package
On-board ST-LINK/V2-1 supporting USB re-enumeration capability
Three different interfaces supported on USB:
- Virtual com port
- Mass storage
- Debug port
LCD 24 segments, 4 commons in DIP 28 package
Seven LEDs:
- LD1 (red/green) for USB communication
- LD2 (red) for 3.3 V power on
- LD3 Over current (red)
- LD4 (red), LD5 (green) two user LEDs
- LD6 (green), LD7 (red) USB OTG FS LEDs
Pushbutton (reset)
Four directions Joystick with selection
USB OTG FS with micro-AB connector
SAI Audio DAC, Stereo with output jack
Digital microphone, accelerometer, magnetometer and gyroscope MEMS
128-Mbit Quad-SPI Flash memory
MCU current ammeter with 4 ranges and auto-calibration
Connector for external board or RF-EEPROM
Four power supply options
- ST-LINK/V2-1
- USB FS connector
- External 5 V
- CR2032 battery (not provided)

More information about the board can be found at the STM32L476G Discovery website_.

Hardware

The STM32L476VG SoC provides the following hardware features:

Ultra-low-power with FlexPowerControl (down to 130 nA Standby mode and 100 uA/MHz run mode)
Core: ARM® 32-bit Cortex®-M4 CPU with FPU, frequency up to 80 MHz, 100DMIPS/1.25DMIPS/MHz (Dhrystone 2.1)
Clock Sources:
- 4 to 48 MHz crystal oscillator
- 32 kHz crystal oscillator for RTC (LSE)
- Internal 16 MHz factory-trimmed RC (±1%)
- Internal low-power 32 kHz RC (±5%)
- Internal multispeed 100 kHz to 48 MHz oscillator, auto-trimmed by LSE (better than ±0.25 % accuracy)
- 3 PLLs for system clock, USB, audio, ADC
RTC with HW calendar, alarms and calibration
LCD 8 x 40 or 4 x 44 with step-up converter
Up to 24 capacitive sensing channels: support touchkey, linear and rotary touch sensors
16x timers:
- 2x 16-bit advanced motor-control
- 2x 32-bit and 5x 16-bit general purpose
- 2x 16-bit basic
- 2x low-power 16-bit timers (available in Stop mode)
- 2x watchdogs
- SysTick timer
Up to 114 fast I/Os, most 5 V-tolerant, up to 14 I/Os with independent supply down to 1.08 V
Memories
- Up to 1 MB Flash, 2 banks read-while-write, proprietary code readout protection
- Up to 128 KB of SRAM including 32 KB with hardware parity check
- External memory interface for static memories supporting SRAM, PSRAM, NOR and NAND memories
- Quad SPI memory interface
4x digital filters for sigma delta modulator
Rich analog peripherals (independent supply)
- 3x 12-bit ADC 5 MSPS, up to 16-bit with hardware oversampling, 200 uA/MSPS
- 2x 12-bit DAC, low-power sample and hold
- 2x operational amplifiers with built-in PGA
- 2x ultra-low-power comparators
18x communication interfaces
- USB OTG 2.0 full-speed, LPM and BCD
- 2x SAIs (serial audio interface)
- 3x I2C FM+(1 Mbit/s), SMBus/PMBus
- 6x USARTs (ISO 7816, LIN, IrDA, modem)
- 3x SPIs (4x SPIs with the Quad SPI)
- CAN (2.0B Active) and SDMMC interface
- SWPMI single wire protocol master I/F
14-channel DMA controller
True random number generator
CRC calculation unit, 96-bit unique ID
Development support: serial wire debug (SWD), JTAG, Embedded Trace Macrocell™

More information about STM32L476VG can be found here:

STM32L476VG on www.st.com_
STM32L476 reference manual_

Supported Features

.. zephyr:board-supported-hw::

Connections and IOs

STM32L476G Discovery Board has 8 GPIO controllers. These controllers are responsible for pin muxing, input/output, pull-up, etc.

For more details please refer to STM32L476G Discovery board User Manual_.

Default Zephyr Peripheral Mapping:

UART_2_TX : PD5
UART_2_RX : PD6
LD4 : PB2
LD5 : PE8

System Clock

STM32L476G Discovery System Clock could be driven by an internal or external oscillator, as well as the main PLL clock. By default the System clock is driven by the PLL clock at 80MHz, driven by 16MHz high speed internal oscillator.

Serial Port

STM32L476G Discovery board has 6 U(S)ARTs. The Zephyr console output is assigned to UART2. Default settings are 115200 8N1.

Programming and Debugging

.. zephyr:board-supported-runners::

STM32L476G Discovery board includes an ST-LINK/V2-1 embedded debug tool interface.

Flashing

The board is configured to be flashed using west STM32CubeProgrammer_ runner, so its :ref:installation <stm32cubeprog-flash-host-tools> is required.

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

.. code-block:: console

$ west flash --runner openocd $ west flash --runner jlink

Flashing an application to STM32L476G Discovery

Connect the STM32L476G Discovery to your host computer using the USB port, then run a serial host program to connect with your Discovery board. For example:

.. code-block:: console

$ minicom -D /dev/ttyACM0

Then, build and flash in the usual way. Here is an example for the :zephyr:code-sample:hello_world application.

.. zephyr-app-commands:: :zephyr-app: samples/hello_world :board: stm32l476g_disco :goals: build flash

You should see the following message on the console:

.. code-block:: console

Hello World! arm

Debugging

You can debug an application in the usual way. Here is an example for the :zephyr:code-sample:hello_world application.

.. zephyr-app-commands:: :zephyr-app: samples/hello_world :board: stm32l476g_disco :maybe-skip-config: :goals: debug

.. _STM32L476G Discovery website: https://www.st.com/en/evaluation-tools/32l476gdiscovery.html

.. _STM32L476G Discovery board User Manual: https://www.st.com/resource/en/user_manual/dm00172179.pdf

.. _STM32L476VG on www.st.com: https://www.st.com/en/microcontrollers/stm32l476vg.html

.. _STM32L476 reference manual: https://www.st.com/resource/en/reference_manual/DM00083560.pdf

.. _STM32CubeProgrammer: https://www.st.com/en/development-tools/stm32cubeprog.html