SPI is a standard used for data communication developed by MOTOROLA It consists of three lines (i.e. MISO, MOSI and SCK) for data transmission as well as for handshake unlike UART (which requires 9 pins for full feature operations). In SPI communication there is only one MASTER controller and one SLAVE controller, and hence the slave addressing is not required. It is a full duplex serial data communication process.
The MASTER can read from MISO line while transmitting data on MOSI line. The MASTER controls the complete process of data transmission and also provides synchronization clock on the SCL line. Since the synchronization is done by the MASTER itself, the SLAVE device need not worry about the clock frequency at other end. The data size is not restricted to 8-bit data.
The main disadvantage in SPI interfacing is that it can be established only for short distance communication unlike
Filed Under: What Is