Editing SPI


'''Serial Peripheral Interface Bus (SPI bus)'''
Connects circuitry with few wires over serial protocol.

SPI supports an unlimited number of peripherals, which may all be identical.

Daisy-chained SPI connects all the devices on a SPI bus in a loop.
In a daisy-chain SPI loop, the serial data out pin (SDO) of each device connected to the serial data in pin (SDI) of the next device in the loop.
A daisy-chained SPI bus uses 4 GPIO pins on the microcontroller, no matter how many SPI peripherals are attached.


Chip-select SPI uses an additional dedicated chip-select pin for each SPI peripheral.


(Other protocols, such as [[I2C]], require each peripheral on the bus to have a different (unique) address).


== Further reading ==

[http://en.wikipedia.org/wiki/Serial_Peripheral_Interface_Bus Serial Peripheral Interface Bus]
* [https://www.sparkfun.com/spi_signal_names a redefinition of SPI signal names: "A REDEFINTION OF SPI SIGNAL NAMES"] by Nathan Seidle, founder of SparkFun Electronics.