🚀 go-pugleaf

Does anyone out there have any experience with real-time data aquisition
on the Amiga?  I have written a level-2 interrupt server (triggered by
the ACK signal) to grab about .5 seconds worth of data from the parallel 
port.  The sampling of the data needs to be fairly fast (like in sampling 
audio frequencies) and precise and REPEATABLE.  If I run in a workbench 
screen the code works well.  If I open a screen of my own (640x200) the 
timing goes to hell even though my server does a Disable() and Forbid().
  I seem to remember some talk about this a while back saying something 
like: the additional screen created some processing overhead via exec or 
intuition (which couldn't be disabled easily without guruing the operating 
system.)  Or perhaps it had to do with the high screen resolution 
interfering with the CPU timing due to DMA access so that a 320x200 
screen was required instead.  Does anyone know or remember?  And what are 
the ways to get around it?  Just use 320x200 screens?  Just use the 
640x200 workbench screen?  Is there a way to get the OFF_DISPLAY/
ON_DISPLAY macro's working so that the display could be temporarily 
disabled?
   Also, is there a "proper" way to tell if your server (as one of many
in a chain) is the intended receiver of the triggering interrupt? It
seems that string gadgets also use level-2 interrupts for keyboard I/O.

  Please reply via email to ron@vicorp.COM.  Thanks!