Posted By
TLC
on 2011-02-09
17:29:18
|  Re: cartridge programming
Yes (...and no... I would have needed to be more precise).
Usual ROM cartridges certainly won't boot up if the Kernal ROM is broken (because they're jumped to by the Kernal reset routine). (They might survive the absence of the Basic ROM, however.)
If the question is, whether some special cartridge could be able to run without the presence of a Kernal ROM (...or anything but the processor + a bare minimum of viable parts), my nose tells met that the answer should probably be yes. I seem to remember a discussion about a rare freezer cartridge that basically "hijacked" the IRQ process by pulling some address lines low, letting the processor fetch some bytes from a purposely mapped-in ROM slice instead of $FFFE/$FFFF of the system RAM (and thus taking control). Exploiting that sort of trick might also help to avoid the Kernal ROM reset routine completely ie. breaking into control before even the reset vector could be fetched from the Kernal ROM.
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