[flatiron]

Back in the day you couldn’t even single step a 6502. IIRC the apple 1 manual had a super smart Woz way to nop the 6502 in between steps to keep it alive.

That being said I love the 6502 and have a few laying around and will play with this on Monday.

[analog31]

I worked on some 6502 based stuff in the early 80s, thanks to a college internship. As I learned from my mentor, the original 6502 was NMOS and had some dynamic registers, i.e., their contents needed to be refreshed, thus limiting how slow the machine could run. But the 65C02 was CMOS with all static registers and could be slowed down to zero through appropriate control of the clock.

The thing we were building for my internship used a very low clock speed to conserve battery power, since CMOS draws current only during transitions.

[flatiron]

Yep. The only 6502s that I’ve seen recently can single step. But it’s still amazing they are being sold to this day!