Description Based on F4 series cheapest chip STM32F401CCU6, competitive price to F1 series But faster speed and own the float calculation function Board lead out all IOs for use. On board resources: 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 Reset buttons. Documentation, schematic see on this page.
