Routines
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33030: Drawing: Step Down One Row
Used by the routine at DrawingSetup.
Moves the screen address down one character row, and undoes that step if it would leave the screen.
Drawing_StepDownOneRow 33030 PUSH AF Step down one attribute row and jump to 33043 if the screen address is not 90.
33031 PUSH DE
33032 LD DE,32
33035 ADD HL,DE
33036 LD A,H
33037 CP 90
33039 JR NZ,33043
33041 AND A Clear the carry flag.
33042 SBC HL,DE Undo the step.
33044 POP DE Restore DE and AF from the stack.
33045 POP AF
33046 RET Return.
View the equivalent code in;
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