Path: utzoo!attcan!uunet!snorkelwacker!ira.uka.de!smurf!urlichs
From: urlichs@smurf.sub.org (Matthias Urlichs)
Newsgroups: comp.sys.mac.programmer
Subject: Re: Serial interface replacement for mouse
Message-ID: <1990Mar20.113904.14207@smurf.sub.org>
Date: 20 Mar 90 11:39:04 GMT
References: <1990Mar19.001639.28530@caen.engin.umich.edu>
Organization: University of Karlsruhe, FRG
Lines: 29

In comp.sys.mac.programmer, article <much.too.long.C.News.ID>,
  kleinow@caen.engin.umich.edu (leonard kleinow) writes:
< Here's a tricky one.  I have a pointing device (a glove) that sends about
< a dozen bytes of data through its serial port to the mac indicating its
< position in space and the positions of its fingers.  I want to be able to
[...]

Open serial port.
Read the appropriate number of bytes from it, asynchronously, with a
completion routine which puts the bytes into the mouse coordinates and calls
said async Read again.

A little bit of assembler programming, no trap patches.
Clean except for the fact that you are poking into the mouse globals, which
probably can't be helped. (A recent tech note documents a more compatible way
to implement a pointer, but which seems only to work for ADB devices. Perhaps
if you install a fake ADB handler or something?)

For best results, install from an INIT so you can use it in every program, and
make a nice cdev interface to set parameters and stuff.

< This will require some patch to the system, I think.  Is there some 
< place these above-mentioned traps have in common I can patch?  Has
< anyone done this already?
<  
See above. You don't need to patch traps.

-- 
Matthias Urlichs