This register holds source x (x=A,B,C) data for
        use by the blitter. It is normally loaded by the
        blitter DMA channel; however, it may also be
        preloaded by the microprocessor.

LINE DRAW BLTADAT is used as an index register LINE DRAW and must be preloaded with 8000. LINE DRAW BLTBDAT is used for texture; it must LINE DRAW be preloaded with FF if no texture LINE DRAW (solid line) is desired.
SEE ALSO: Blitter programming
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