SPI Multiplexer PUBLIC

Not provided.

There is effectively a 2-device limit on the SPI bus for the Raspberry Pi, because all the SPI pins are fixed and only two cable-select lines are offered.

To get around this, I used logic inverters and a shift register (the box outline) as described in the diagram. This requires that I shift a value into the register indicating which device I want just before I conduct SPI conversations. This technically introduces some delay in my communications, but it is not significant for my purposes, as I'm only running around 1 Mhz.