Re: Serial port connection (null modem) not working
On Thu, Aug 23, 2007 at 11:17:11AM -0800, Ken Irving wrote:
> On Thu, Aug 23, 2007 at 03:06:45PM +0000, Douglas A. Tutty wrote:
> > I have yet to find a ready-made null-modem cable that is actually wired
> > correctly for use by UNIX. How it should be wired can be found in
> > several places accessible as packages on Debian.
>
> I've never had any trouble with null modem cables purchased off-the-shelf,
> though that may be due to simple requirements. Unless you're doing
> something fancy, or maybe using high data rates, many applications really
> only need a 3-wire connection, and the other pins shouldn't matter.
> I normally disable hardware handshaking, don't need the ring or the
> other wired (and swapped) signals.
>
When I did this, I ran 115200 across a 50 foot serial line so I need the
handshaking and hardware flow controll. Granted for a terminal at 9600
three wires is just fine. For a ppp serial link where one would
otherwise use Ethernet, a little tweaking gives great results. This
setup was for using a laptop without Ethernet for backing up with rsync
as well as ssh access.
Doug.
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