[kiwidrew]

Yes but how long is Microchip going to continue producing the 16V8? They're the only remaining manufacturer. At least with 74xx138 decoders you have several suppliers available -- not to mention the choice of multiple logic families to select from.

If you're willing to accept address aliasing (i.e. chips appearing at more than one memory address) you can simply use multiple '138 decoders in parallel to make a 1-of-24 or 1-of-32 decoder. In fact that's precisely why the '138 has so many enable inputs: the one active high (G1) and two active low (~G2A and ~G2B)enable inputs let you build a 1-of-24 decoder using three '138 chips and zero additional glue.

[noone_youknow]

Fair point, but I happen to have a few thousand ATF16V8BQLs in stock, so I'm not worried for the time being :) Originally (on breadboard) the project didn't use any programmable logic, but board space dictated that I switch to them when I did the first PCB.

[jacquesm]

That's the difference between doing it professionally and doing it on a hobby budget.

[LIV2]

Doesn't matter too much for hobby projects though, even if they go EOL there's still plenty on eBay.