The STM32 MCU features ARM’s Cortex-M3 core and a peripheral set that includes high resolution 12-bit analog-to-digital converters with a 1 µs conversion rate and a high speed DAC. Fast communications are possible with high-speed serial connections through a 4 Mbps UART, 18 Mbps SPI, USB, and the ability to toggle the I/O pins at up to 18 MHz. The Flexible Static Memory Controller and SDIO interface allows connection of a broad range of external memory options and peripherals. I2S supports external audio codecs and DACs.