Down the STM32 Bare Metal Rabbit Hole

Introduction

This repository is a collection of my code projects as I learn the aspects of programming an STM32F103C8 Cortex M3 micro controller at the "bare metal" register level. I will be creating example code for most all aspects of the µC including SPI, USART, I2C, DMA, etc.

With a working toolchain, all projects can be built from within their project directory. The master.mk file REQUIRES modification in order to set the paths to the build tools.

The following tools are used for these projects:

• ARM-GCC compiler toolchain.
• stm32flash flash tool using the on-board STM32 serial bootloader over UART.
• st-link flash tool using an ST-LINK V2 USB programmer.
• Official STM32 CMSIS files as part of their STM32Cube MCU packages.

Development Hardware

All example projects are using a "Blue Pill" board as the target hardware platform.

Common Directories

CMSIS/

Contains the Cortex CMSIS files needed to build the projects. These files have been repackaged from the official STM32 CMSIS files.

template/

The template directory contains the files necessary to start a new STM32F103 project.

gdb/

The gdb directory contains gbd command files used for debugging and flashing.

Example Projects

01 Hello World/

The first project being the ubiquitous "Hello World" as a "Blinken Light".

02 Warp Speed/

Extends "Hello World" to configure the clock to run at max speed (72MHz.)

03 Tick Tock/

This extends the previous projects implementing the Cortex SysTick timer in order to create a 1ms interrupt. This interrupt will become the clock used to time the LED heartbeat. This becomes the code for the project template.

04 USART/

This project works as a simple serial test platform using USART1 to transmit and receive data by implementing a chargen and echo service.