STM32 Blue Pill (F103CB)

The board as it appears on the Velxio canvas, with its full pin map read live from the simulator (regenerated by scripts/gen-boards.mjs, so it always matches what you can wire).

Family: STM32 · Languages: Arduino C++

About this board

The 128 KB Blue Pill. Same Cortex-M3, same pinout and same peripherals as the F103C8 — twice the flash.

Many boards sold as “Blue Pill” carry the CB die, which is why both are here: the flash size is modeled, so a build that fits on one and not the other tells you the truth about your hardware.

Start here

New Blue Pill F103CB project opens the editor with this board and a working blink sketch. STM32 boards need a paid plan — see plans.

Pins (40)

• PB12
• PB13
• PB14
• PB15
• PA8
• PA9
• PA10
• PA11
• PA12
• PA15
• PB3
• PB4
• PB5
• PB6
• PB7
• PB8
• PB9
• 5V
• GND
• 3V3
• GND
• GND
• 3V3
• NRST
• PB11
• PB10
• PB1
• PB0
• PA7
• PA6
• PA5
• PA4
• PA3
• PA2
• PA1
• PA0
• PC15
• PC14
• PC13
• VBAT

Every pin above is clickable on the canvas — click one to start a wire. Board-level behavior, quirks and example links live on the family page.