RE:RE:A82: Galaxian bug... solved?


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RE:RE:A82: Galaxian bug... solved?





>It's 960 because 16*12 + 768 = 960. Thats all Derrick Ward can remember 
>and he wrote that part of the code.
>    It has something do with the use of Patrick Davidson's Display 
>Screen routine instead of ROM_CALL(DISP_GRAPH).  
>   Sam
>
  I have found the CrASH problem. For a while I thought it had something 
to do with the contrast changer or save feature because they were the 
only unique things in Orzunoid and Galaxian that are in both games. But 
now I know it is Patrick Davidson's Display routine that CrASH has a 
problem with. I didn't realize Orzunoid uses the exact same display 
routine. Its used because it is much faster than the other routines 
out(at least thats what I've been told). One line of the display routine 
code says "ld    hl,GRAPH_MEM+(16*12)" Thats why the number is 960. Its 
768+(16*12)= 960. THIS IS THE ROUTINE CRASH DOESN'T LIKE. This is a huge 
step. Now maybe Barubary or CrASH_Man can tell me what needs to be fixed 
in the Display routine to work with CrASH correctly. Heres the 
problematic routine:

Display_Screen:
         call     DISP_DELAY
         ld       a,7
         out      (16),a

         ld       c,17
         ld       a,$80
         ld       hl,GRAPH_MEM+(16*12)
loop_display:
         call     DISP_DELAY
         out      (16),a
         inc      a
         ld       e,a
         ld       a,$20
         call     DISP_DELAY
         out      (16),a
         ld       a,e

         call     DISP_DELAY \ outi
         call     DISP_DELAY \ outi
         call     DISP_DELAY \ outi
         call     DISP_DELAY \ outi
         call     DISP_DELAY \ outi
         call     DISP_DELAY \ outi
         call     DISP_DELAY \ outi
         call     DISP_DELAY \ outi
         call     DISP_DELAY \ outi
         call     DISP_DELAY \ outi
         call     DISP_DELAY \ outi
         call     DISP_DELAY \ outi

         cp       $c0
         jr       nz,loop_display
         ret

If Barubary or CrASH_Man (or Dines for that matter) could tell me what I 
need to change I would appreciate it.

Evil Sam

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