A learning project for Zephyr RTOS targeting the STM32 Nucleo G474RE dev board! I have always seen Zephyr projects in the wild and want to document my learning process. I've used FreeRTOS in the past and want to rewrite some projects using Zephyr 🙂

Hardware


Board	ST Nucleo G474RE
MCU	STM32G474RE (ARM Cortex-M4F, 170 MHz)
UART	LPUART1 via onboard ST-Link VCP (PA2/PA3)
LED	LD2 on PA5

Connect via USB to the Nucleo's ST-Link port

Features

Interrupt-driven UART RX - ISR writes bytes into a ring buffer
Dedicated RX thread - sleeps on a semaphore, wakes on data arrival
Line accumulation - buffers input until \r or \n
Formatted output - prints received line with length and uptime timestamp
LED - on PA5 configured via devicetree overlay (for testing)

Getting Started

Prerequisites

Zephyr SDK installed
west installed and workspace initialized

Build & Flash

west build          # board is set in CMakeLists.txt
west flash

(optionally)
west debug

Serial Monitor

Connect a terminal to the ST-Link Virtual COM Port at a baud rate of 115200:

Personally, I just use PuTTY!

Type a line and press Enter:

─────────────────────────────
│ RX: hello
│ Len: 5,   Time: 6741
─────────────────────────────

License

Apache 2.0