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8141: Drawing: Advance The High Coordinate
Used by the routines at DrawingSetup and Drawing_PlotTheSelectedPixel.
Advances the high coordinate. When it wraps from FF, it is put back and the routine returns zero.
Drawing_AdvanceTheHighCoordinate 8141 INC D Step the high coordinate on and return unless it wrapped to zero.
8142 RET NZ
8143 DEC D Put the high coordinate back to FF.
8144 LD H,A Keep A in H.
8145 XOR A Set the zero flag.
8146 LD A,H Bring A back from H.
8147 RET Return.
View the equivalent code in;
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