Richard,

Yes, I was thinking of using discrete 373' etc, simple and as others point out not very flexible.
I am planning to use a PSD81x chip, but need two more 8 bit ports.
I also touched on the use of maybe the MAX3000 from Altera, to implement a port(s), Ive worked chips from Altera, and www.Clear-logic.com has some lower cost replacements. Plus the base line MAX-PLUS software is free.

Yes I know the PSD835 has five ports, but I want to stay thu-hole.

Thanks to all for the input.


MArtin