Re: C64 buses when RESET is asserted

Date: Mon, 8 Apr 2013 14:30:34 -0400 (EDT)
Message-ID: <>
> On April 8, 2013 at 1:54 PM Michał Pleban <> wrote:
> Hello!
> Jim Brain wrote:
> > I still think your idea is fine, just just need to isolate the ADDR and
> > DATA bus of the ROM from the PCB socket while you are updating it. I
> > think the PETVet does something similar, though it's doing it on the CPU
> > socket, not the ROM socket.
> Yes of course. But if I need additional chips to isolate the buses, it
> will be easier to use a Flash chip instead of SRAM, and make the 6502
> update it with data pulled from the SD card...
Well, if the additional HW is not too much, I'm happy to add it to ROM-el.
 People have asked for such a capability many times.  I think I ran into
problems finding the correct select logic, as /OE and /CS on the ROMs are not
active on a write cycle to those areas of memory.

> Regards,
> Michau.
> Message was sent through the cbm-hackers mailing list

       Message was sent through the cbm-hackers mailing list
Received on 2013-04-08 19:00:04

Archive generated by hypermail 2.2.0.