I've been pondering another strategy for the Lisa PROMs needed for the #AppleLisaClone project. Could an (E)EPROM be used instead? With the appropriate adapter and fast enough response time, might it work? I think vintage arcade folks do this now. I've successfully used EPROMs before in a #C64 for the PLA.
I have a stash of W27C512 that are 45ns which I think is fast enough to replace a MMI 6309. There would be a lot of wasted space but who cares?
Thoughts?