STM32F103RET6 Minimum System Board

It has the following advantages: 
1. Ideal for beginners to use with two breadboards together.
2. Supports USB, a 5V main power supply module, and a 3.3V backup power supply test module
. 3. Theoretically supports both ST-Link and J-Link debugging (currently tested with ST-Link programming).
4. Almost all usable pins are exposed.
5. BOOT0 and BOOT1 can be switched to 3.3V or ground via jumpers (this is based on the Jiangsu University of Science and Technology board).
6. The schematic uses 24-pin headers or pin headers on both sides. For breadboards, it is recommended to use pin headers and solder them downwards.
 
A brief introduction to the main buttons: 
SW1: RST, reset button .
SW2: Connects to PC13 as a test pin. To test if the program can run, set the PC13 pin high and then press SW2. If LED2 lights up, the soldering is successful and the chip is running normally.
SW3: WAKE UP pin (connects to PA0, used for wake-up).