St stm32 32 bit flash arm cortex m microcontrollers st stm32f401vct6 the stm32f401vct6 is a 32 bit arm based microcontroller with 256 kbytes of flash memory and a cpu frequency of 84mhz the microcontroller incorporates the high performance arm cortex m4 risc core which features a floating point unit fpu a full set of dsp instructions and a memory protection unit mpu enhance application security an extensive range of enhanced peripherals and ios connected to two apb buses and standar