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Glen \Wiley\ Wilson
 
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Default Cheap and Nasty Knotmeter

On Wed, 21 Jan 2004 09:18:16 -0800, "Lloyd Sumpter"
wrote:

Can I get a new sender, with proper documentation so I know how it
works, and hook it into my laptop?


I'm afraid I don't have anything like an answer to your question,
though I would have thought that the sender wouuld output pulses
rather than a variable voltage, leaving the instrument to count the
pulses. You can see some readymade data acquisition solutions at B&B
electronics http://www.bb-elec.com/ but I suspect the cost would
qiuickly approach that of a new instrument, if cost is your major
objective.

If it is pulse data, you might be able to attach (properly
buffered/amped) it to something like the RTS line of the serial port.
You can definitely capture RTS events if you take direct control of
the port, and probably even if you use the standard MSComm activeX
object. Since Windows is kind of crappy when it comes to doing
anything in real time, you'd likely lose pulses occasionally though.
I think you'd be better off to count them with a circuit and just pass
along the count. Don't know nuthin bout no parallel ports, though.

I'm actually more interested in your thought process. I have
something of a professional interest in displaying this sort of thing
on PCs. To date, I've worked with NMEA data, but I've been asked to
look into direct acquisition of certain data, so I'm wondering what
leads you to want to do this. Of course, if it's just cost, that's
pretty self-explanatory.

__________________________________________________ __________
Glen "Wiley" Wilson usenet1 SPAMNIX at worldwidewiley dot com
To reply, lose the capitals and do the obvious.

Take a look at cpRepeater, my NMEA data integrator, repeater, and
logger at http://www.worldwidewiley.com/