SPI communication with STM32, SPI in polling mode, SPI in interrupt mode, SPI in DNA mode, SCLK, MOSI, SS The SPI (Serial Peripheral Interface) protocol, or rather the SPI interface, was originally devised by Motorola (now Freescale) to support their microprocessors and microcontrollers. Unlike the I2C standard designed by Philips, the SPI interface has never been standardized; nevertheless, it has bec ....