The STM32F103C8T6 (HCDVBD0033 / Black pill) Development Board is a low cost but feature rich alternative to an Arduino. The board features an ST Microelectronics STM32F103C8 Arm microprocessor running at a 72MHz clock speed. Coupled with 64K of Flash and 20K of SRAM this development board provides a powerful alternative to an Arduino. This development board is also not short on peripherals with 30 I/O pins, 14 of which can be configured as 12 bit ADC inputs, 12 as PWM with most pins being 5V tolerant. Supplied with the module are a set of 0.1" pitch headers (require soldering) which provide the option of breadboard mounting it with easy connection of standard Dupont cables.

For programming there is the option of using the STLink download adapter (see item HCDVBD0016) or a standard USB to 3.3V TTL adapter (see item HCMODU0051). Support for this board can be added to the Arduino IDE via the board manager feature. See the following blog post for full instructions on how to quickly get up and running here:

http://blog.hobbycomponents.com/?p=703



Feature comparison to Pro Mini:






Specification:

Part number: HCDVBD0033
Power: 3.3V or 5V via microUSB
Processor: ST Microelectronics STM32F103C8
Flash memory: 64K
SRAM: 20K
I/O (MAX): 30
Analogue pins: 14
PWM pins: 12
UART: 3
SPI: 2
I2C: 2




Pinout:






Programing via serial bootloader with Arduino IDE:






Example Arduino 'blink' sketch: 

	Code: #define LED_PIN PB12 void setup()  {   pinMode(LED_PIN, OUTPUT); } void loop()  {   digitalWrite(LED_PIN, HIGH);   delay(1000);   digitalWrite(LED_PIN, LOW);   delay(1000); }