Routines
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48442: Screen Address One Pixel Below
Used by the routine at ClearPixelBlock.
Moves down by one pixel line in the display file.
Input
HL Screen address
Output
HL Screen address one pixel line down
ScreenPosition1PixelBelow 48442 INC H Move down to the next pixel line in the character row.
48443 LD A,H Return if that is still inside the character row.
48444 AND 7
48446 RET NZ
48447 LD A,L Otherwise move on to the next character row in the third...
48448 ADD A,32
48450 LD L,A
48451 AND 224 ...and return if that is still inside the third of the display.
48453 RET Z
48454 LD A,H Otherwise move on to the next third.
48455 SUB 8
48457 LD H,A
48458 RET Return.
View the equivalent code in;
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