STMicroelectronics STM32U073MCI6, 32 bit ARM Cortex M0+, STM32U073x8/B/C Microcontroller, 56 MHz, 256kB FLASH, 81-Pin

The STMicroelectronics Ultra low power microcontrollers based on the high performance Arm Cortex -M0+ 32 bit RISC core operating at a frequency of up to 56 MHz The device embed high speed memories up to 256 Kbyte flash memory and 40 Kbyte SRAM with hardware parity check, and an extensive range of enhanced I/Os and peripherals connected to APB and AHB buses, and a 32 bit multi AHB bus matrix. They also embed protection mechanisms for embedded flash memory and SRAM, such as readout protection and write protection.

4 to 48 MHz crystal oscillator