stm32-to-linux

This repository is ZhaoBuyan's embedded learning portfolio, documenting the learning journey from bare-metal STM32F429 development, gradually transitioning to FreeRTOS and embedded Linux driver/BSP directions. The development environment is based on the STM32F429IGT6 development board (Cortex-M4F @180MHz, 1MB Flash, 256KB SRAM), using the STM32CubeMX + Keil MDK5 + ST-Link toolchain, with the debug serial port being USART1 @115200-8-N-1. The repository has a clear directory structure, mainly containing experimental projects under the STM32F429 directory: LED_Key_Control implements register-level GPIO operations for RGB tri-color LEDs and keys; light0.0.1 is an early test project. The learning progress covers GPIO register operations (directly writing GPIOx->MODER/BSRR, understanding push-pull output and common-anode LED driving), non-blocking tri-color cycling (using HAL_GetTick() timestamps and state machines, avoiding HAL_Delay), and key scanning (polling plus software debouncing, non-blocking). Future plans include EXTI, timers, UART, SPI, I2C, DMA, and FreeRTOS. The README.md under each experiment directory records what was done, the observed phenomena, problems encountered, and the resolution process, making it easy to review and share.