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Re: Double-Width HiRes
"Matthew T. Russotto" writes ...
>
....
>
> You can't display from DHR page 2.
....
Don't know how often it's done; but, sure, you can display from the second
DHR page ($4000-$5FFF Main and Aux mem).
After BLOADing the DHR pic, you move the AUX part at $2000-$3FFF (Main
mem) to $4000-$5FFF (Aux mem).
By the way, doing the move is pretty easy: You set the Start, End, and
Destination Start of the move. Then you Set Carry and JSR to $C311. For
example, to do the move mentioned above, addresses $003C-$003F and $0042, $0042
would be set to ...
00 20 FF 3F 00 40
$003C $003D $003E $003F $0042 $0043
Start End Dest
Here is an Applesoft BASIC sub to display DHR page 2 after the move:
186 REM 80ST/OFF & DHR ON- HIRES/ON+GR/ON+DHR/ON+PAG2+MIX/OFF 80COL/ON
187 POKE 49152,0:ZZ = PEEK (49239) + PEEK (49232) + PEEK (49246) +
PEEK (49237) + PEEK (49234): POKE 49165,0: RETURN
Displaying from DHR page 2 ($4000-$5FFF in Main and Aux mem) might be
useful if you want to subsequently load in hires pics at Hires page 1
($2000-$3FFF Main mem) and maintain the capability to show the DHR pic at any
time.
Rubywand