If I want to read a (bunch of) 74HC165 chip(s) over an SPI port on a microcontroller, this is simple enough. Connect them through Q7 to DS on each, apply the final Q7 to MISO, notCE to SS and CP to SCK. This works fine.
But now how do I share the SPI bus with other devices that I want to read? The 165's Q7 output is never hi-Z, so I can't share the MISO pin with other devices. I'd need some way to "detach" it - a buffer of some kind.
I know there are 74-series chips that have various buffers that can be made hi-Z (such as a 74HS240) but that's a whole additional chip just to be able to share the shift register. Perhaps some cunning way to put a transistor between the final Q7 and the microcontroller's MISO, controlled by the SS line?
Edit: Alternatively, can someone suggest some other parallel-in serial-out shift register that does have a tristate serial output line, and therefore suitable to use on an SPI bus?