Topic       : The GFA-Basic Compendium
Author      : GFA Systemtechnik GmbH
Version     : GFABasic.HYP v2.98 (12/31/2023)
Subject     : Documentation/Programming
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Index Size  : 28056
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Compiled on : Atari
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@hostname   : CAB     
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View Ref-FileVSYNC

This command is used for the synchronisation of the screen display. When this
command is issued, the computer pauses until the vertical scanning line (raster
scan) reaches the top of the screen. This results in much less screen flicker.
VSYNC can be used, for example, in the animation of screen sections using GET
and PUT.

Example:

    t%=TIMER
    FOR i%=1 TO 100
      VSYNC
    NEXT i%
    PRINT SUB(TIMER,t%)/200

--> This displays the time for 100 scans of the screen to occur.

Memo: VSYNC has been reported as not working with MiNT.
      Alternate method for MiNT:

    PROCEDURE waitvbl
      vbl_%=LPEEK(&H466)       !global for max speed (local is slower)
      WHILE LPEEK(&H466)=vbl_%
      WEND
    RETURN

Vsync()+