Project Title

Standalone STM32F103C8T6 Development Board (Minimal System)

What’s the project about?

I designed a custom standalone development board using the STM32F103C8T6 microcontroller.

It replicates the functionality of the popular "Blue Pill" board but with:

Only the essential components

Better pin breakout

Clean power management

Full control of the boot and reset lines

This board is designed for prototyping, learning, and embedded system projects.

Why did I make it?

The Blue Pill has:

Many unused pins

Irrelevant components for some embedded projects

Poor layout for custom enclosures

I needed:

A compact board for custom enclosures

Full control over component choice

Easy soldering and programming access

This project helped me:

Practice full schematic and PCB design flow

Learn about STM32 boot process and minimum system requirements

Build boards ready for final product integration

How does it work?

The board includes:

STM32F103C8T6 MCU (ARM Cortex-M3, 72 MHz)

3.3V LDO regulator (AMS1117) for onboard power supply

BOOT0 jumper to switch between programming and normal mode

Reset button

SWD header for programming and debugging

All GPIOs broken out to headers

Optional crystal oscillator (8 MHz) and load capacitors

You can power the board through:

USB (via header)

External 5V source

Programming is done via:

USB to Serial using USART1 (PA9/PA10)

Or SWD with ST-Link V2

It runs any firmware built using STM32CubeIDE or PlatformIO.