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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