The example architecture can be found in Motorola’s SPI standard – “SPI Block Guide”. CPOL defines, whether SCK is Low (0) or High (1) when bus is idle (nSS is High). CPHA defines, whether first (0) ...

Serial Peripheral Interface (SPI) is not really a protocol, but more of a general idea. It’s the bare-minimum way to transfer a lot of data between two chips as quickly as possible, and for that ...