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Re: Serial console on second port?

It should perhaps be pointed out that all such cables should in fact be "null"-modem cables, since we're talking about connecting two DTEs.
Too bad that almost no one except DEC actually read the RS-232 specs.
Now, MMJ isn't exactly RS-232, but it's close enough to be discussed in the same sentence here. (Lots of companies seem to have been confused about DTE and DCE, as well as which gender the connection should be depending on this.)

One nice property of MMJ is also that for a null-modem cable, you should connect 1-6, 2-5, 3-4. So it's symmetrical. So the easy way to see if a cable is a null-modem cable is just to inspect the connectors. If they are turned the same way at both ends, it's a null-modem cable, and if they are the opposite ways, it's a straight cable.


Steve Davidson wrote:
The actual DEC cable part number is BC16E-XX where XX is the length in
feet.  The most common were 10 and 25 foot lengths.  They appear to be
null-modem cables (I'm looking at one now).  One other supplier (in the
US, anyway) is:



-----Original Message-----
From: port-vax-owner%NetBSD.org@localhost 
[mailto:port-vax-owner%NetBSD.org@localhost] On
Behalf Of Martin Husemann
Sent: Monday, March 30, 2009 04:42
To: port-vax%NetBSD.org@localhost
Subject: Serial console on second port?

I have a Vax Station 4000 M96 and would like to use it with serial
It apparently has two serial ports, one MMJ and another one for the
with a DB25 connector.

Since MMJ adapters (or even connectors) are pretty hard to get hold of
(or unreasonable expensive) - is there an easy way to just use the DB25
connector instead?


P.S.: there seems to be no "console mode switch" to select keyboard or
on this machine (like on the M60) - is it hidden somewhere or should I
it to just work?

P.P.S.: I have a SFX graphics, but lacking a video cable for that
on solving that too), so I'm basically blind - please excuse the stupid
newbie questions.

Johnny Billquist                  || "I'm on a bus
                                  ||  on a psychedelic trip
email: bqt%softjar.se@localhost             ||  Reading murder books
pdp is alive!                     ||  tryin' to stay hip" - B. Idol

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