Routines
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62821: Step Pen Left
Used by the routines at DrawingFill and DrawingLine.
Moves the pen one pixel left. The top bit stays set while X is on the picture, and is clear once the pen has passed the left edge.
StepPenLeft 62821 DEC D Move the pen left and return when it is still on the picture.
62822 BIT 7,D
62824 RET NZ
62825 INC D The pen passed the left edge, so step back and tell the caller it did not move.
62826 LD H,A
62827 XOR A
62828 LD A,H
62829 RET Return.
View the equivalent code in;
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