SCK (Serial Clock) - The clock pulses which synchronize data transmission generated by the master.

MOSI (Master Out Slave In) - The Master line for sending data to the peripherals.

MISO (Master in Slave Out) - The Slave line for sending data to the master.

SPI has following four lines MISO, MOSI, SS, and CLK A master is usually a microcontroller and the slaves can be a microcontroller, sensors, ADC, DAC, LCD etc.īelow is the block diagram representation of SPI Master with Single Slave.

A SPI can have only one master and can have multiple slaves. Interfacing Nokia 5110 Graphical LCD with ArduinoĪ SPI has a master/Slave communication by using four lines.Programming AVR microcontroller with SPI pins.Interfacing 3.5 inch Touch Screen TFT LCD with Raspberry Pi.SPI Communication with PIC Microcontroller PIC16F877A.SPI communication is previously explained in other microcontrollers: SPI is synchronous serial communication means the clock is required for communication purposes. That is a master can send data to a slave and a slave can send data to the master simultaneously. SPI has a full-duplex connection, which means that the data is sent and received simultaneously. SPI interface was found by Motorola in 1970. SPI (Serial Peripheral Interface) is a serial communication protocol. For the sake of avoiding confusion, we have still used the old terminologies in the article, but we encourage our readers to practise the new terms. It is expected that the terms MOSI/MISO and SS will be changed to SDI(Serial Data In) /SDO(Serial Data Out)and CS(Chip Select) respectively. According to this new resolution, people are encouraged to use the word 'Controller' in place of 'Master' and 'Peripheral' in place of 'Slave'.

Important Note: A new resolution is underway to improve the terminologies used in SPI communication by removing office words like 'Master' and 'Slave' while discussing SPI communication.

Spi serial communication protocol