From: Michele Andreoli (m.andreoli@tin.it)
Date: Sun Apr 23 2000 - 22:28:06 CEST
On Sun, Apr 23, 2000 at 07:39:58PM +0100, Clive Wright nicely wrote:
> Michele Andreoli wrote:
> >
> <snip>
> >
> > Do not worry about that: I know AT command. My only doubt is about
> > cable, because usually crossover is needed: transmit pin connected
> > to receiving pin, on the other side, and so on.
> >
> Unlike RS232 the connection to a modem is a wire loop there
> is no separate rx and tx line and a zero volt (ground plane)
> connection is not required.
> A crossover is not needed but if one is present it will not
> make any difference as long as the loop is intact. Telephone
> instruments usually receive their power from a (voltage
> limited) constant current source at the telephone exchange;
> but as modems do not depend on the line for power, the lack
> of a DC power source should not present a problem.
>
This seems very raisonable: from physical point of view, this is
a AC current over two wire. What is missing in my harddisk, is a
tools to track what modem is really receiving (a part LED).
Michele
-- I'd like to conclude with a positive statement, but I can't remember any. Would two negative ones do? -- Woody Allen --------------------------------------------------------------------- To unsubscribe, e-mail: mulinux-unsubscribe@sunsite.auc.dk For additional commands, e-mail: mulinux-help@sunsite.auc.dk
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