darn threading email clients, I didn't read that what I wrote had already been covered in another part of the thread. I'd also forgotten that vic doesn't have a reset line. With all the extra lines and logic required to detect reset vector fetching then it would be better to have a reset header on the rom that could be wired up to the cpu reset if you wanted that functionality. On 28/12/2016 11:37, smf wrote: > On 27/12/2016 14:03, bwack wrote: > >> Interesting approach. Regarding the detection of $fffe on the address >> bus, I >> suppose a MCU can do that. > > The rom will only see 0x1ffc/1x1ffd as it only has a0-a12 and I assume > /CE only goes low when you're accessing the rom and you just see the > address bus change for other addresses. > > It's made more complicated because VIC and 6502 share the bus, I don't > know if a VIC bad line can split the reset vector fetching. Maybe not > when actually resetting as VIC will be reset too, but JMP ($FFFC) > might be affected. > > > Message was sent through the cbm-hackers mailing list Message was sent through the cbm-hackers mailing listReceived on 2016-12-28 12:01:34
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