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MEGA65 User Guide
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Improve "C65 Compatibility ROM Layout" table #585

Open dansanderson opened 6 months ago

dansanderson commented 6 months ago

From ki-bo, Jan 1 2024:

While looking at this table again, and also seeing it is claiming C65 compatibility layout, we may want to split up $2C000-$2CFFF further. The original C65 ROM had a larger DOS than what fit into $20000-$23FFF (I think because that one still contained REL support, which we removed at some point). In order to get this mapped, the excess ROM area needed was put into $2C000-$2C7FF, which will land directly after the other DOS area. Thus, when mapping DOS to $8000-$BFFF, the additional ROM fragment needed beyond that automatically landed at $C000-$C7FF. The interface ROM itself is therefore just 2KB and sits at $2C800-$2CFFF (mapped to $C800-CFFF). We may want to adapt above table to split up the $2C000 row like this:

$2C000-$2C7FF RESERVED $2C800-$2CFFF INTERFACE