Organization: Freshman, CIT general, Carnegie Mellon, Pittsburgh, PA
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Newsgroups: comp.robotics
Message-ID: <EfM5_Ya00WBM458UUW@andrew.cmu.edu>
Date: Fri, 22 Jan 1993 15:01:40 -0500 
From: James Ryan Miller <jmce+@andrew.cmu.edu>
Subject: Sonar and the 68HC11
Lines: 21

    I am curious if anyone has programmed a 6811 to find distances with
one of those polaroid sonar things.  Right now, I have the transducer
and the 6811, but I need to determine what interface circuitry is
needed.  I know you can buy kits from polaroid that has a thing that
does all the decoding and determines distance and stuff, but that is NOT
what I want.  

    Here is how I'm envisioning it ... The 6811 could pulse a trigger
line which has the transducer xmit a "ping".  When the ping was
received, it would pulse a line that the 6811 would time, and calculate
distance.  With the great Input Capture features of the 6811, the
software should be easy, but how much circuitry is needed to have these
two nice digital lines at the computer to actually driving the
transducer.

    Any references, ideas or suggestions are appreciated.

    Thanks,
        Ryan Miller
        jmce+@andrew.cmu.edu

