I want to expand number of I/O ports of my microcontroller. For this purpose, I want to use a pair of shift registers (one for output: "serial in - parallel out"; and one another for input: "parallel in - serial out"). But there is one problem, I have to connect parallel I/O pins of shift registers, so I need a special shift register which can be disabled, and when disabled it must give high impedence at its pins.
I searched using Google, but couldn't find an IC like this.
I will apreciate if you could suggest me one.
Or, maybe, should I prefers a different method for this port expension?