SPI (Serial Peripheral Interface) is a communication method that allows electronic devices to exchange information quickly.
In this lesson, you will learn how SPI works, what wires it uses, and why it is useful. People commonly use SPI to connect microcontrollers to sensors, displays, and memory modules.
What is SPI?
SPI is a communication protocol, meaning a set of rules for exchanging data between devices.
It uses two types of devices:
Controller: Starts and controls communication.
Peripheral: Sends and receives data, following the controller's instructions.
The Four SPI Wires
MOSI: Sends data from the controller to the peripheral.
MISO: Sends data from the peripheral to the controller.
SCLK: Provides a clock signal to keep communication synchronized.
CS (Chip Select): Chooses which peripheral to communicate with.
How Does SPI Work?
The controller selects a peripheral using CS.
The controller generates clock pulses through SCLK.
Data is exchanged through MOSI and MISO.
The controller ends communication by deactivating CS.
SPI can send and receive data simultaneously, making it fast and efficient.
Why Use SPI?
SPI can send and receive data with multiple devices through the same pins except the CS pin, which needs to be unique for each device, making it very efficient.