[A86] Re: address


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[A86] Re: address




Imagine an array in memory like this:
[0][ ][ ][ ][ ][ ][ ][ ][ ][ ]
 ^  ^
 hl de

Executing an ldi instruction would copy (hl) to (de):
[0][0][ ][ ][ ][ ][ ][ ][ ][ ]
 ^  ^
 hl de

then increment hl & de:
[0][0][ ][ ][ ][ ][ ][ ][ ][ ]
    ^  ^
    hl de

Repeating this across the length of the array (minus one, i think):
[0][0][0][0][0][0][0][0][0][0]
                            ^  ^
                            hl de


I'm not sure what the flag does, but it probably tells the os that the
graph needs to be redrawn.

-josh


On Tue, 10 Apr 2001 20:16:10 -0700 "Garam Song" <kreeblex4@hotmail.com>
writes:
> 
> How come in asm files people do
> 
> cleargraphdraw:
> ld hl,_plotSScreen
> ld de,_plotSScreen + 1
> ld bc,1024
> ld (hl),0
> ldir
> set graphflags,(iy + graphflags)
> ret
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