30 years ago, [Dave] found himself up a C128D creek without a paddle. His main monitor was on the fritz, and he needed to use his C128D in 40-column mode to run old C64 programs for development purposes. Normally this is only possible through the low quality composite out, but no composite monitor was available. Needs must, so he got to coding a workaround that would allow the C128D to output in 40 column mode through the higher-quality RGBI output.
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