On 12/8/2016 7:24 PM, MindFlareRetro wrote: > Not to step on any toes, but how are eBay sellers like Coprolite Computer > By-Products pulling this off with their "Coprolite Mega-16 Cartridge > Commodore 64 128 w/27C801 Eprom For 64 16k programs" ... > https://goo.gl/MojkUi. > > <http://cbm-hackers.2304266.n4.nabble.com/file/n4662039/CoproliteMega16.jpg> Not sure the question, but the design is simple: the rotary switch picks 4 bits of the address, and the dip switches pick another 2. The 2 diodes, and one of the little resistors create a wired 'OR' gate to select the ROM when eitehr ROML or ROMH are low. The rest of the switches tie the 6 address lines high when the switches are not pulling them low. Is this the design you'd prefer, one with switches for banking, and 16kB (it makes it a bit harder to use for 8kB images because you have to buy a 16kB EPROM , and you really need 1 more switch, on the GAME line, since that line should be high for 8kB ROMs. Jim Message was sent through the cbm-hackers mailing listReceived on 2016-12-09 05:00:02
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