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From: etobkkc@etn.ericsson.se (Karlsen Bjorn)
Subject: Re: How is a Loopback connector made?
In-Reply-To: 35002_4401@uwovax.uwo.ca's message of Mon, 19 Apr 1993 17:26:28 GMT
Message-ID: <ETOBKKC.93Apr21084447@aliboats.eto.ericsson.se>
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Reply-To: etobkkc@hisoy.etn.ericsson.se
Organization: Ericsson AS
References: <1993Apr19.132628.1@uwovax.uwo.ca>
Date: Wed, 21 Apr 1993 07:44:47 GMT
Lines: 27

35002_4401@uwovax.uwo.ca writes:

>I need to know the Pins to connect to make a loopback connector for a serial
>port so I can build one.  The loopback connector is used to test the 
>serial port.
>
>Thanks for any help.

From a recent BYTE magazine i got the following:

[Question and part of the answer deleted]

  If you are handy with a soldering iron, the loopback plugs are easy to
make.  On a serial RS-232 nine-pin port, use a female DB-9 connector and
connect pins 1 to 7 to 8; 2 to 3; and 4 to 6 to 9.  For serial RS-232 
25-pin ports, you'll need a female DB-25 connector with pins 1 to 7;
2 to 3; 4 to 5 to 8; 6 to 11 to 20 to 22; 15 to 17 to 23; and 18 to 25
connected.  To test a Centronics 25-pin parallel port, you'll need to
connect pins 1 to 13; 2 to 15; 10 to 16; 11 to 17; and 12 to 14 in a male
DB-25 connector.

					-Stan Wszola
---

I haven't tried it. Use at own risk.

-KKC-  etobkkc@hisoy.etn.ericsson.se
