3 ms·

I've been looking for a detailed explanation on this, because I would like to know how they read the PC. The New Advanced User's Manual describes the flag at &

I've been looking for a detailed explanation on this, because I would like to know how they read the PC. The New Advanced User's Manual describes the flag at &FE34 on the Master and B+ and I've read this thing about using the PC from a few places but I haven't found any specifics. Could you clarify? How do you know from the outside what's in the PC?

ddingus 3y ago
Would they not just mooch the address off the address bus?
- morcheeba 3y ago
  Yep. The 65C02 has a SYNC output that goes high to indicate an instruction is being fetched on the current cycle. Since there is no cache, it's pretty simple to use this to determine the PC.
  - ddingus 3y ago
    Thought so. From there, it is a bit of logic to map the chip selects to make the writes and reads come and go from the intended resources.
  - forinti 3y ago
    That's it then. I was missing the sync pin. Thank you.