About this product
The Blue Pill is a third-party development board commonly built around an STM32F103C8T6 ARM Cortex-M3 microcontroller, nominally running at up to 72 MHz with 20 KB of SRAM and 64 KB of guaranteed flash. Header rows bring out 3.3 V GPIO along with I2C, SPI, UART, timers, and analog inputs, and programming is done over SWD or a serial bootloader. STMicroelectronics notes that Blue Pill boards are not official ST products, so device authenticity and board implementation can vary.