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Switching ROM's on the fly?
Is there a way to change the ROM on a Commodore while it is running? I have an idea for using a large Flash ROM type device, but instead of a physical switch for changing ROM images, I want to make an internal IEC type device to change the ROM while the computer is running. In theory, this would let the ROM socket become a virtual storage device of a kind. The call to the IEC Device number would be able to switch ROMs on the fly allowing access to custom ROM routines from a much larger set of ROMs. In the case of a Flash device in place of the ROM, perhaps the IEC could also flash ROM slots. This of course requires the Commodores not having fit if the ROM content change. I would set the IEC device to a high number like 30 or 32 so it wouldn't interfere with normal IEC operation.
I though Penfold did this,

I though Penfold did this, but it turns out he was using the serial port on a CIA to do the configuration.

If you want to just have N ROMs, you can use the Megabit ROM board. You could probably look at the SD2IEC for the basics of reading and responding to IEC bus signals. You would be a lot better off using the BURST protocols though, a lot easier to handle ;) Or just snooping the BUS at say D50A or something like that, above the MMUs memory range but below any mirrors. So you can just poke memory to get it to swap.

I don't want to use any IO
I don't want to use any IO that might conflict with something else. Except for writing ROM's to flash, there is not much need to address the ROM switches speeds higher than the IEC port.
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