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From: oster@dewey.soe.berkeley.edu (David Phillip Oster)
Newsgroups: comp.sys.mac.hypercard,comp.sys.mac.programmer
Subject: Re: Reaction Time stacks : can I do this?
Message-ID: <27081@ucbvax.BERKELEY.EDU>
Date: 9 Dec 88 17:15:53 GMT
References: <6012@mva.cs.liv.ac.uk> <21792@apple.Apple.COM> <21826@apple.Apple.COM> <3820@pt.cs.cmu.edu> <794@husc6.harvard.edu>
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Reply-To: oster@dewey.soe.berkeley.edu.UUCP (David Phillip Oster)
Organization: School of Education, UC-Berkeley
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If you use a digitizing tablet connected to the Mac serial port at
19.2KBaud, you'll be talking at about 2kBytes a second. Since it takes
about 5 bytes for a tablet to send a position record (depends on the brand
of tablet.) it takes 2.5m sec to get the position data. This means that
you can't measure events that are closer together in time than that.
However, since the tablet introduces a uniform delay, and since it begins
transmitting as soon as the pen comes within range of the tablet,
you can measure events to an accuracy greater than 2.5ms. Just watch out
for tablet continuous mode: in this mode many tablets transmit as
infrequently as one hundred times a second.  

Once again, you'll need to draw the images yourself, rather than leaving
them for hypercard to draw, and be sure to allow for the fact that the
drawing is quantized in time by the video hardware to be no faster than 60
times a second.

--- David Phillip Oster            --"When we replace the mouse with a pen,
Arpa: oster@dewey.soe.berkeley.edu --3 button mouse fans will need saxophone
Uucp: {uwvax,decvax}!ucbvax!oster%dewey.soe.berkeley.edu --lessons." - Gasee