STM32 “Blue Pill” is a popular, and cheap (>$2) development board based on STMicro STM32F103C8T6 Arm Cortex-M3 microcontroller and programmable with the Arduino IDE.
I’ve just been informed the board got an upgrade of sorts with a “Blue Pill 2” board featuring either STM32F401CCU6 or STM32F411CEU6 Arm Cortex-M4F microcontroller, and a USB Type-C port for power and programming. It’s black, so instead, I’ll call Black Bill as some others appear to do.
Specifications for the Blue Pill & Black Pill boards (new features in bold):
- MCU (one of the other)
- STMicro STM32F103C8T6 ARM Cortex-M3 MCU @ 72 MHz with 64KB flash memory, 20KB SRAM.
- STMicro STM32F401CCU6 Arm Cortex-M4F MCU @ 84 MHz with 256 KB flash, 64KB SRAM
- STMicro STM32F411CEU6 Arm Cortex-M4F MCU @ 100 MHz with 512KB flash, 128KB SRAM
- Storage – Footprint for SPI flash
- USB
- Blue Pill – 1x micro USB port for power and programming
- Black Pill – 1x USB Type-C port for power and programming
- Debugging – 4x pin SWD header or USB port
- Expansion – 2x 20-pin with power signals, I2C, SPI, GPIOs, ADC inputs, etc…
- Misc
- Reset button, power and user LEDs.
- Boot mode selection
- Blue Pill – Two jumpers
- Black Pill – Boot button
- Black Pill STM32F411 only – Power button
- Power – 5V via USB, 2.0-3.6V power via 3.3V pin on SWD header.
- Dimensions – 5.3cm x 2.2cm
The new boards get a faster microcontroller with an FPU and much more memory and storage to play with, and you could even solder your own SPI flash.
“Blue Pill” is just a nickname for this type of board, and we can see the PCB is named WeAct V1.3. I can not see Arduino support yet for the board, but an STM32F401CC board called BlackBill F401CC is supported in Arduino Core for STM32 repository, and I believe it may be this exact board (TBC). One person is also specifically working on a MicroPython port for WeAct v1.3 board.
Black Pill / WeAct v1.3 board can be purchased on Aliexpress for $2.79 (STM32F401CCU6 ) or $3.96 (STM32F411CEU6).
Thanks to iridiumsat for the tip.
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Jean-Luc started CNX Software in 2010 as a part-time endeavor, before quitting his job as a software engineering manager, and starting to write daily news, and reviews full time later in 2011.
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