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Re: Connecting a console.



Quoth Ira Abramov on Thu, Jun 29, 2000:
> On Thu, 29 Jun 2000, Nimrod S. Carmi wrote:
> > My question is -- does anyone know how is it done, and what configuration
> > do I need to set up for this to work, on console side and on the machine
> > side .... ?
> 
> the VT should just be set to the same line speed and soft flow control,
> remember to cross the serial cable because both computer and terminal
> are DTE, so a modem cable won't do. simple 1-1, 2-3, 3-2, 7-7 should be
> fine for a D-type 25.

I believe it should not be a crossed cable, but a straight one
(i.e., 2->2, 3->3, etc.).  Connecting pins 2, 3, 7 should be
enough.  You may also connect 8 and 20.

> if your linux has only 9 pin outputs, I don't
> remember the pinout (sorry).

Good source of information is:

http://www.BSDI.COM/bsdi-man?proto=1.1&apropos=0&msection=ALL&query=rs-232

For crossed cables, switch between:
TD  <-> RD
RTS <-> CTS
DCD <-> DTR

BTW, I don't see why non-crossed cables (in general, not just
RS-232) were invented at all.  Life would be much easier if there
were only crossed cables.  All equipment would transmit on pin X
and receive on pin Y, no matter what it is -- a DTE or a DCE
(using RS-232 terms).  True, making straight cables is easier
(you don't need to worry about the protocol, unless it's TP), but
handling two different types of cables for each protocol, and
using slightly freaky things like crossing adaptors, is a pain in
the neck, for various values of neck.

I'm in love with telephones.  Only two wires in the cable, and
you may connect them in any order you like.

Vadik.

-- 
If you think C++ is not overly complicated, just what is a protected
abstract virtual base pure virtual private destructor, and when
was the last time you needed one?
		-- Tom Cargill, C++ Journal, Fall 1990.

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