What Is the Serial Peripheral Interface?

Serial peripheral device interface, SPI, is the abbreviation of English Serial Peripheral interface. Motorola first defined it on its MC68HCXX series processors. SPI interface is mainly used in EEPROM, FLASH, real-time clock, AD converter, as well as between digital signal processor and digital signal decoder. SPI is a high-speed, full-duplex, synchronous communication bus. It only uses four wires on the pins of the chip, which saves the pins of the chip, saves space on the PCB layout, and provides convenience. Because of this simple and easy to use feature, more and more chips now integrate this communication protocol, such as AT91RM9200.