Serial Peripheral Interface Bus (SPI) is a digital communication bus commonly used for interconnecting chips on a printed circuit board.

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• The master lowers the CS line, indicating a transaction is starting
• The master starts outputting a clock signal (a "square wave") on the CLK line
• At each rising edge of the CLK line:
  • The master samples the MISO line. If it's high, that's a 1, if it's low, a 0.
  • The slave samples the MOSI line. If it's high, that's a 1, if it's low, a 0.
• The transaction goes on until the master stops sending a CLK signal, and raises the CS line.

SPI on 

Include Page
_def_chip_eterna _def_chip_eterna

The libraries provided with the 

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