常用通信协议总结

SPI

there is no spec for spi, so some of this definition is a little bit loose.

quote from spi: the serial peripheral interface by ben eater

↑　cpol = x　cpha = x

↑　cpol = 0　cpha = 0

↑　cpol = 0　cpha = 1

↑　cpol = 1　cpha = 0

↑　cpol = 1　cpha = 1