Re: TI-H: TI-Modem


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Re: TI-H: TI-Modem




Grant, that's the biggest load of crap I've heard on this list
in a long time. You can't simply connect an ADC and DAC to a
phone line and call it a modem. At the very least you'd need
some kind of VFO and PLL to convert the tones back into a voltage at the 
other end. Not to mention that the two "modems" have to test
line conditions and adjust baud rate, have some form of error
correction, and so on. And then there is the issue of phone line
voltage transients and all of that. Also, phone lines tend to 
shift frequencies occasionally so some kind of fuzzy logic 
wouldn't hurt either. There are commercial modem chips out 
there but I don't think any of them do above 2400 baud. You'd
be better off learning how internal ISA modems work and picking 
up two el-cheapo internal 2400's at a computer show. Or.. 
better yet... just use Biffle's TI TCP/IP redirector and a 
-=PC=-. Does anybody really want to play ztetris over the 
phone network anyway?

Man, some of these projects are becoming absolutely insane. This
isn't supposed to be a flame... but I wish for once you could
post working plans to something without giving us a bunch of
bullshit about clarisworks and how Linux crashed your
computer. Certainly Clarisworks can save word documents for
us PC guys and if you don't know how to use linux, there are
plenty of good documentation sites on the net. Regardless, the
original poster didn't ask for a hacker's solution, he wanted
to know how to use the graphlink to connect his calculator to
a modem. I believe there is info on ticalc.org about doing that.

Bryan Rittmeyer
mailto:bryanr@flash.net
http://www.bridges.edu/horizon/

Grant Stockly wrote:
> 
> The thing I had just checks the calc transmit for activity and adc or
> serial receive...  Then decides what to do.
> 
> >So, who all has successfully connected an external modem
> >to their calc using the TI-Graphlink method, and connected to
> >something?  If so, tell what calc you used and what program
> >please.
> >
> >Thanks!
> >
> >Lee


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