STMicro STM32F401CCU6 Arm Cortex-M4F MCU @ 84 MHz with 256 KB flash, 64KB SRAM
Based on F4 series cheapest chip STM32F401CCU6, But faster speed and own the float calculation function Board lead out all IOs for use.
VB can connect coin battery power supply
On board 32.768Khz crystal, and 25Mhz main crystal
Typc-C programming port
V+/V- can connect external ADC reference voltage, default to power voltage.
B2 boot select pin is selectable for boot configuring or normal GPIO.
SW debug port