Hello! Rob Clarke wrote: > I have around 20 spare 27C020 2mb eproms which I was planning on using > which would hold 32 x 8k images. With this method I would only fit 16 > images and as there's only 3 16k MAX cartridges, it's rather a waste. > I'm wondering if there is a way of using /ROML to override the latched > values on A16, A15 and A14 so all the $8000-$9FFFF images only use the > bottom 4 x 8k images on the eprom? Then I'm afraid you either need to use two EPROMs, or two latches. Two EPROMs, one RAM and one latch will unfortunately not fit in a cartridge. Two latches, RAM and EPROM - maybe, I haven't tried but it's still hard. Unfortunately if you do not switch to a larger EPROM, you may be stuck with 8 kB images. > How about AND'ing pin 10, which is /IO2 on the 64 and /CIA on the MAX, > with A7? On the assumption that none of the MAX ROM's don't write to any > of the CIA's mirrored registers during their normal operation we could > use a write to $DC80 and $DF80 on the MAX and 64 respectively? /IO2 is not /CIA on the MAX, it's the CIA's shift register output. Regards, Michau. Message was sent through the cbm-hackers mailing listReceived on 2013-10-20 20:01:10
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