The "Blue Pill" is a highly popular, extremely affordable, and compact STM32F103 board. Equipped with the Arduino bootloader, it seamlessly integrates into the Arduino environment for programming. Operating at a clock speed of 72 MHz, this board stands out. The STM32F103C8T6, boasting a robust microcontroller, features a 32-bit CPU based on the ARM Cortex-M3 Architecture crafted by STMicroelectronics. Its performance surpasses that of the Arduino UNO, demonstrating a remarkable 4.5 times increase in speed.

Features:

• Form Factor: Small footprint
• Power Supply Options:
  • Flexible board power supply from USB VBUS or external source (3.3V, 5V)
• User Interaction:
  • User LED: LED1
  • User Button: RESET
• Programming/Debug Port
• USB Connector: Micro-B USB

Specifications:

• ARM 32-bit Cortex–M3 CPU core with a maximum frequency of 72 MHz.
• Memories: contains 64 Kbytes of Flash and 20 Kbytes of SRAM
• GPIO Pins – 32 with external interrupt capability
• Timers – 3 16-bit Timers, 1 16-bit PWM Timer
• PWM Pins – 15
• Analog – 10 channels of 12-bit ADC
• I2C – 2 I2C Peripherals
• USART – 3 USART Peripherals with hardware control
• SPI – 2 SPI Peripherals
• Other Peripherals – USB 2.0 Full Speed, CAN 2.0B

The Blue Pill Board Pinout:

The STM32F103C8T6 MCU offers multiple functions for each pin. It's important to note that certain IO pins are 5V tolerant, allowing seamless connection with 5V-compatible IO devices. Firmware installation can be accomplished either through USART1 using the permanently installed serial bootloader or through SWD with an ST-Link adapter.

During regular operation, the Boot1 jumper (PB2) is available for custom applications. It is recommended to resell the frame of the sensitive USB socket. To avoid a short circuit, it's crucial not to supply power to the board simultaneously via USB and a 5V power source. However, an additional 3.3V supply is acceptable.

How to get started with Blue Pill :

• Tutorial Link