It kind of sounds like you're thinking of building something new with it though
Not really something new
, per se: specifically, this particular project is a personal challenge: could I build a state-of-the-art, feature-packed microcomputer for production... in late 1975? Yes, if I were creating a new system, I would use the 65C02; but in 1975, of course, there's only NMOS (and yes, I'm making sure that my code doesn't contain any RORs
I'm currently reworking the DRAM strobe timings (MK4096-16) on my prototype, and was wondering if I could get away with using an early write cycle instead of a delayed write strobe, which makes signal generation a little easier (with consequent reduced chipcount).
As far as I can tell with my oscilloscope, both the (Rockwell) 1MHz 6502s I've looked at seem to always have valid data by Phi2+120ns (and probably earlier than that, possibly consistently as early as Phi2+80ns), no matter which instructions I throw at them. However, I have no idea how representative that is (i.e. should I rely on that if I were designing for production?).
Specific concern aside, of course now I'm also just curious and would like to know regardless