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30 lines
937 B
ObjectPascal
30 lines
937 B
ObjectPascal
{This example demonstrates the use of the segment_to_descriptor()
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function.
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It switches to VGA mode 13h (320x200x256 color), creates a selector
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to the memory (based at $A000:0000), clears this memory with color
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15 (white) and waits until the enter key is pressed }
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uses go32;
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var
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vgasel : Word;
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r : trealregs;
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begin
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{ set VGA mode 13h }
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r.eax := $13; realintr($10, r);
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{ allocate descriptor to VGA memory quickly; it could be done
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with allocate_ldt_descriptors() too, but we would have to
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initialize it by ourselves... unlike segment_to_descriptor()
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which automatically sets the limit and the base address
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correctly }
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vgasel := segment_to_descriptor($A000);
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{ simply fill the screen memory with color 15 }
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seg_fillchar(vgasel, 0, 64000, #15);
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{ wait for a return press }
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readln;
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{ back to text mode }
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r.eax := $3; realintr($10, r);
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{ don't deallocate vgasel, that can't be done }
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end. |