I seem to recall using 8255's with the 8080- a few years before the x86!

Also, why are 8255's such a bad match for 8051's? I seem to recall many successful products used both.


Personally, I wouldn't use a 8255 these days - I don't know who still makes them?

Nothing wrong with using a '573 - there's no reason why you can't have it occupy many addresses like the 8255 - just make sure you only read/write to one address!

Nowadays, there's no reason why you can't use a small cpu to replace logic - think of the cost of board space vs a number of 'jellybean' logic devices. There's many devices less than USD$1.