NTSC composite artifact color is something typically relegated to computers with off-the-shelf graphics hardware. We associate it with the Apple II mainly, which used it in its high resolution modes. TRS-80 Color Computer fans also know it very well, because it was the only color available in that computer line's graphics until the Model 3. IBM PCs also used with more frequency than was commonly known in the early days in CGA graphics cards. But Commodore didn't rely on off-the-shelf 74-series logic to drive its home computers' displays. It had bought the MOS company and all its chip fabrication expertise. Its computers used real graphics chips and they displayed real color. They didn't need the composite tricks to get their graphics working and they didn't need boards devoted to graphics either. But I have come across some information which suggests that the assumption that the Commodore 64 did not support composite artifact color may not be supportable.
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