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From: bender@oobleck.Eng.Sun.COM (Michael Bender)
Newsgroups: sci.electronics
Subject: Re: TV remote control codes
Message-ID: <7725@exodus.Eng.Sun.COM>
Date: 9 Feb 91 05:50:35 GMT
References: <2407.27B2CBE1@ofa123.fidonet.org> <43935@ut-emx.uucp>
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In article <43935@ut-emx.uucp> greg@ccwf.cc.utexas.edu (Greg Harp) writes:
>This looks like a good time to jump in with a question I thought of this 
>morning.  I came up with the (probably not very original) idea of "digitizing"
>remote control codes with my computer...
>			[...]
>Basically, my idea was to make 1-bit samples of the phototransistor's state
>at up to, say, 50K/sec (I don't know how fast I could push this yet).  I 
>would then play back these samples using an IR LED.  At that speed could I 
>expect a positive result?  Also, what is the typical length of the code before
>it repeats?  I could search for repeating patterns to shorted sample length.

you know what might be slick?  have two "learn" modes to your device; one
learn mode would just sample the incoming data stream at some arbitrary
sample rate and store whatever it received from the phototransistor, and the
other learn mode would be a smarter mode, where you could tell your device
what kind of remote you had, i.e.  a Sony TV remote, or a Panasonic VCR
remote, etc... and the code in your computer would know that these specified
remotes have a certain data stream, and you could sample at a rate at which
the "known" remote outputs data, rather than sampling at an arbitrarily fast
rate.  of course, if you know the data rate of a given remote, you may
probably also know what the data format is, so that you wouldn't have to
sample the remote at all, you could just synthesize the data with your
computer.

manufacturers should get their act togther, and come up with a SINGLE remote
protocol, with well-defined extensions for future options, rather than
everyone going out and inventing their own format.  but like most other
things in this world, they probably see more $$$$ in having a proprietary
format.

mike

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