Serial Peripheral Interface

Serial Peripheral Interface (SPI) is a de facto standard (with many variants) for synchronous serial communication, used primarily in embedded systems for short-distance wired communication between integrated circuits. SPI follows a master–slave architecture, where a device (variously called master, leader, controller, main...) orchestrates communication with one or more devices (variously called slave, follower, target, sub...) by driving the clock and chip select signals.

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