Kunal Kandekar wrote:
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8255 is still useful in that it allows you to tie up 12 of your uC pins (1 port + 4 control lines) in exchange for accessing 24 I/O lines (three 8-bit ports, one of which is bit-addressable). Hence its very useful for parallel I/O or communication. I've seen it used successfully in a number of projects.

thanx kunal, but circuit size is a major issue, always trying to make things work with smallest possible size and the 40 pin 8255 consumes lots of space.
and exchanging 12 pins for 24 is bad also for size, i'd rather use i2c input or the ics Peter suggested.
Thanx