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From: dk1y+@andrew.cmu.edu (David Kosmal)
Newsgroups: comp.sys.mac.programmer
Subject: mac programming question
Message-ID: <UYFX8Hy00Xo=Q11UwL@andrew.cmu.edu>
Date: 14 Apr 89 18:01:55 GMT
Organization: Electrical and Comp. Engineering, Carnegie Mellon, Pittsburgh, PA
Lines: 24


I have a mac programming question concerning some lower level hardware stuff,
and I was wondering if anyone out there could help me:

I am interested in developing a simple program for a psychology experiment that
will measure the time interval between a the appearance of a display on the
screen and when the viewer presses a key.  This time interval must be measured
within 1/100th of a second.

Can it be done with a standard mac keyboard?  If so, were are some of the low
level entry points that I can use to do this?  I have looked through various
parts of Inside Macintosh, but still I am not sure what exactly happens when a
key is pressed.  Ideally there would be some kind of interrupt that I could
catch.

Also, can I use any of the system timers to measure the interval?  Again, Inside
Macintosh is not precise on this.

I know the basics of the Macintosh toolbox and am very familiar with the 68000.
Any help, including books to look at, would be appreciated.

Thanks,

David Kosmal