[aprssig] RJ45/RS232 Again
Fred Atkinson, WB4AEJ
fred at wb4aej.com
Mon Mar 13 15:37:57 CST 2006
OK, let me be more specific. If you are familar with using a crossover
cable to connect the serial port of a PC to a Cisco router, switch, or
firewall, you will have no trouble following this.
I use Cisco rollover cables a lot because I teach computer networking.
I want to make an adapter to adapt the leads in a Cisco rollover cable to
the RS232 interface on a TNC-2. Therefore, the same cable I use to
interface to Cisco devices I will be able to use [with this adapter] to
connect to the RS232 port on a TNC-2.
A rollover cable is called just exactly what the pin out describes. It
is as follows:
RJ45 to RJ45
1 to 8
2 to 7
3 to 6
4 to 5
5 to 4
6 to 3
7 to 2
8 to 1
Generally, you have a DB9 to RJ45 female adapter on your computer's
serial port, a rollover cable, and then the other end of the rollover cable
mates with the console (serial) port on a Cisco device.
I have a few RJ45F to DB25M adapters from our good friends at Jameco.
Of course, you get the honor of setting the pins yourself. I am trying to
determine the correct way to pin it out so I can use this arrangement to
talk to the RS232 interface on the TNC-2.
Any feedback would be appreciated.
----- Original Message -----
From: "Daron J. Wilson" <daron at wilson.org>
To: <fred at wb4aej.com>; "'TAPR APRS Mailing List'" <aprssig at lists.tapr.org>
Sent: Monday, March 13, 2006 2:37 PM
Subject: RE: [aprssig] RJ45/RS232 Again
> What's on the modular plug end of this? I'm assuming your TNC is the
> assuming this is a blue cisco 8 pin cable with modular plugs on it, but
> is plugged into the other end of the cable?
> Oddly enough, 8 pin modular plugs and RS-232 implementation vary depending
> on the equipment. I guess I missed where you were going with this to
> > -----Original Message-----
> > From: aprssig-bounces at lists.tapr.org [mailto:aprssig-
> > bounces at lists.tapr.org] On Behalf Of Fred Atkinson
> > Sent: Monday, March 13, 2006 11:24 AM
> > To: aprssig at lists.tapr.org
> > Subject: [aprssig] RJ45/RS232 Again
> > Hello,
> > I've revised that drawing showing the correct color codes for ch
> > of the RJ45 leads. You can view it at
> > http://paws.wcu.edu/fatkinson/APRS/RS232_RJ45.pdf.
> > I've connected a Cisco rollover cable to it and plugged it into my
> > TNC-2. But I'm not getting any data from it. I am reasonably confident
> > that the TNC-2 is working.
> > Any idea what is wrong here?
> > 73,
> > Fred, WB4AEJ
> > _______________________________________________
> > aprssig mailing list
> > aprssig at lists.tapr.org
> > https://lists.tapr.org/cgi-bin/mailman/listinfo/aprssig
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