The STM32F401VEH6 runs an ARM Cortex-M4 at 84 MHz with 512 KB Flash and 96 KB RAM. The 81 GPIOs are available on the 100-UFBGA package.
The peripheral list includes I²C, SPI, USART, USB OTG, SDIO, I²S, and a 16-channel 12-bit ADC — enough to talk to an external sensor bus, log data to an SD card, and drive a codec for audio feedback. Brown-out reset and POR are on-chip; no external supervisor needed for basic power-fail handling.
