On 10/18/2012 12:22 AM, firstname.lastname@example.org wrote: > > > * - how about using the extra space for selecting-in some cart images? I mean I have a need for three KERNALs. Can imagine a need for four. Beyond that I find it difficult to imagine a daily use setup that would need more KERNALs always present. But I can imagine using e. g. three or four KERNALs and one or two or three ROM cart images that would autoboot with CBM80 when selected at $8000. To make it best as I can think of now I would use the room for four KERNALs and two ROM carts. That will need some extra wiring since you need to grab the _EXROM or _GAME line from the PLA and also their corresponding chip select lines. The logic would then only decode the cart image if it also detects the matching _EXROM/_GAME line being low. And you'll also need at least a 4 input AND gate (74LS21) for the _OE/_CS signal for the EPROM. We're getting to the point where the logic is getting a bit out of hand. :) Gerrit Message was sent through the cbm-hackers mailing listReceived on 2012-10-18 18:00:11
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