68kMLA Classic Interface

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two binaries in a 27c512 (Apple IIc)
Posted by: bibilit on 2025-09-04 00:41:21 i was thinking using two binaries in a 27C512 eprom and swapping from one or another for a Standard Rom or the newer 4X. Anyone has done that already ? I think using a switch on pin 27 (A 14) to get it working (probably even using the standard logic board bridges to do so)
Posted by: KennyPowers on 2025-09-04 15:30:15 i was thinking using two binaries in a 27C512 eprom and swapping from one or another for a Standard Rom or the newer 4X. Anyone has done that already ? I think using a switch on pin 27 (A 14) to get it working (probably even using the standard logic board bridges to do so) I have a similar arrangement in an Osborne that allows using an external switch to choose between the stock ROM and a 3rd party ROM by just toggling the high address line. Don't know why that wouldn't work here too 👍
Posted by: Arbee on 2025-09-10 09:39:40 Yeah, this is a super standard thing to do with old computers. I'd recommend against changing the switch with the IIc powered on, but should be fine otherwise.
Posted by: KennyPowers on 2025-09-10 09:43:52 Yeah, this is a super standard thing to do with old computers. I'd recommend against changing the switch with the IIc powered on, but should be fine otherwise. Yeah, the Osborne definitely didn't like it when I did that, but I had to do it at least once...big red button syndrome 😆
Posted by: Arbee on 2025-09-10 09:51:34 🤣 I totally get it. On the IIc it would probably even be OK if you followed up with a Control-Open Apple-Reset, but I still wouldn't do it regularly.
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