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Re: Apple II Music Video - Welcome to the Jungle!!



David Wilson wrote:
Michael J. Mahon wrote:

The troublesome one, which Frank already knows about, is that ProDOS
is reluctant to trample on the primary text page, so double buffering
awaits a fix for that problem...


With good reason - the screen holes can be very important to your disk
controller's operation...

If you want to try it, clear bits 0-3 in $BF58.

Right.  And they seem not to cause much trouble for Oasis (!).

Here is the double-buffered (page-flipping) version of the player:

 10  REM  **********************
 20  REM  *                    *
 30  REM  * Move Movie Frames  *
 40  REM  *  by Frank Milliron *
 50  REM  *  (modified by MJM) *
 60  REM  **********************
 70 :
 80 D$ =  CHR$ (4)
85 IF PEEK (104) < > 32 THEN POKE 104,32: POKE 32 * 256,0: PRINT D$"-play.movie"
 90 BX = 3072: REM  $400 + $800
 100 GS = 49235: REM  Graphics softswitch base address
 110 FS = 1024: REM  frame size
 120 MV$ = "movie": REM   (Or use dialog to select movie.)
 130 FR = 6826: REM   (Or first two bytes could be number of frames.)
 140  GR : REM  Set Graphics page 1 and clear
 150  POKE GS - 1,0: REM  Select nomix
 160 BY = 0: REM  Initial byte offset
 170 BF = 2048:GP = 2: REM  $800 for first frame
 180  POKE 48984,192: REM  De-protect Primary text page
 190 :
 200  FOR I = 1 TO FR: REM  Loop over all frames
 210  PRINT D$"BLOAD "MV$",b"BY",l$400,a"BF
 220  POKE GS + GP,0: REM  Select loaded page
 230 BY = BY + FS: REM  Advance to next page offset
 240 BF = BX - BF: REM  Toggle GR pages ($800/$400)
 250 GP = 3 - GP: REM  Toggle GR page numbers (2/1)
 260  NEXT
 270  POKE 48984,207: REM  Re-protect Primary text page
 280  TEXT : HOME : END

Note that it automatically relocates itself to $2000 if it is not
run at that address, so there's no need for "EXEC.ME.FIRST".

If run in Oasis at 4.7MHz, it syncs almost exactly with the
music--or with the original music video at:

http://www.youtube.com/watch?v=_zuIQkjm78o

It's kind of interesting to watch the two running simultaneously
in two windows.  ;-)

-michael

NadaNet networking for Apple II computers!
Home page:  http://members.aol.com/MJMahon/

"The wastebasket is our most important design
tool--and it's seriously underused."