> Hmmmm... quite simple.
>
> Skipping the paging parts, assuming you have code at 16384-32767 and screen
> at 32768-65535, and ROM0 at 0-16383....
>
> loop1:
> ld b,50 ; this will sometimes give slightly more than a second,
> ; cos the code below will take some time to execute
> halt ; interrupts must be enabled. If you like, you could
> ; replace this with a scan-line check
> djnz $-1
> ld hl,32768
>
> ld a,(hl) ; see below
> inc a ; see below
> ld (hl),a ; see below...
> jr nc, loop1
> ld bc,24576
> loop3:
> inc hl
> ld a,(hl) ;
> inc a ;
> ld (hl),a ; ditto
> jr nc, loop1
> dec bc
> ld a,b
> or c
> jr nz, loop3
> ;bc has got to 0 -- hit the end of the screen...
>
> ;now if (hl)=0, it's finished...
> ld a,(hl)
> or a
> ret z
> jr loop1
Coudn't it been done even simpler?
loop1 ld hl,(32768+24576-1)
loop2 inc (hl)
jr nc, loop2
loop3 dec hl
inc (hl)
jr nc,loop3
bit 6,h ; or 'ld a,h; or a,127'
jr nz,loop1
ret
Why wait for screen update? You won't bother to see them all
anyway :)
-Frode 'not flaming'
--
Frode Tenneboe, ECP/PT, CERN, CH-1211 Geneva 23, Switzerland
[EMAIL PROTECTED] http://www.himolde.no/~frodet
