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One-parting some Commodore 64 utilities for fun and profit

I've got a few retrocomputing bucket list items I'm slowly working down, and a couple of them involve some little Commodore 64 games I've ha...

That kind of patch is ordinarily trivial and usually you can find what needs to be changed by looking for any Kernel SETLFS calls to $ffba, the routine that sets the channel number, device and secondary address. Although for a certain period of time it was heavily advertised, and seemed very well regarded by reviewers, I know little about its history other than that it was originally written in 1983 by Mark R. Rubin and Omni Unlimited and distributed by City Software in Milwaukee, Wisconsin. I dithered over patching all of those calls out as well and seeing what was left, but it dawned on me I had already determined Doodle's entry point, so all I should need to do was drop a breakpoint when it got there and save memory from $0801 to $b55f (the very end of module03), then jump back in at $501a with the BASIC ROM banked out.

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