Routines
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39581: Add Width To Address
Used by the routines at DrawGraphic_Mirrored, DrawGraphic_RotatedLeft, DrawGraphic_Transposed, DrawGraphic_RotatedHalf, DrawGraphic_TransposedFlipped, SetAttributes_Mirrored, SetAttributes_RotatedLeft, SetAttributes_Transposed, SetAttributes_RotatedHalf and SetAttributes_TransposedFlipped.
Adds the width of a graphic to DE, to move on one row.
Input
B The width of the graphic
DE The address
Output
DE The address plus the width
AddWidthToAddress 39581 LD A,B Fetch the width of the graphic.
39582 ADD A,E Add the low byte of the address.
39583 LD E,A Keep the new low byte in E.
39584 LD A,D Fetch the high byte of the address.
39585 ADC A,0 Add the carry.
39587 LD D,A Keep the new high byte in D.
39588 RET Return.
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