From owner-freebsd-hackers Mon Sep 23 07:02:12 1996 Return-Path: owner-hackers Received: (from root@localhost) by freefall.freebsd.org (8.7.5/8.7.3) id HAA06750 for hackers-outgoing; Mon, 23 Sep 1996 07:02:12 -0700 (PDT) Received: from etinc.com (et-gw-fr1.etinc.com [204.141.244.98]) by freefall.freebsd.org (8.7.5/8.7.3) with SMTP id HAA06728 for ; Mon, 23 Sep 1996 07:02:09 -0700 (PDT) Received: from dialup-usr11.etinc.com (dialup-usr11.etinc.com [204.141.95.132]) by etinc.com (8.6.12/8.6.9) with SMTP id KAA14738; Mon, 23 Sep 1996 10:10:20 -0400 Date: Mon, 23 Sep 1996 10:10:20 -0400 Message-Id: <199609231410.KAA14738@etinc.com> X-Sender: dennis@etinc.com X-Mailer: Windows Eudora Version 2.0.3 Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" To: "Louis A. Mamakos" From: dennis@etinc.com (Dennis) Subject: Re: VC support, *BSD and atm/frame/isdn Cc: hackers@freebsd.org Sender: owner-hackers@freebsd.org X-Loop: FreeBSD.org Precedence: bulk > >> I don't think it's particularly efficient, but it's >> not expected to be running under very heavy usage in this version. >> I believe that they went out and did a scan of several providers to >> see if they could use them but somehow ended up doing it that way. >> I do know that they had a hard time trying to work out what pinouts to >> use for connecting a V35 connector to a connector small enough for >> a back plate, and that they liked your DB25 implimentation. >> I've scanned the literature but I haven't found an "Official" >> or even "defacto" standard on how to do this.. the V35 connector is SOO >> clunky. I've been meaning to ask you... did you find that pinout >> somewhere, or did you make it up..? > >Please, don't invent a new pin out for the connector! Use a DB25 and >have it be EIA-530 compatible. This is essentially a superset of the >V.35 "spec" in terms of the line drivers and receivers, and using a >simple adapter cable, you can get to a V.35. I think that EIA-530 is >recommended for new applications, and certainly the cost is lower, too. Well, I think that the V.35 "hack" that most of us use is a "subset" of the standard EIA-530, rather than the other way around....but you are correct. > >Though in most cases, your customers can just purchase EIA-530 compatible >CSU/DSUs, and use a straight-thru DB25 cable. That way, there are no >large, clunky Winchester connectors around at all to cause injury. Be careful, you really should use a twisted pair 25pin cable, not a cheapo RS-232 25 pin cable, particularly for high speeds. Its still cheaper than V.35.... Dennis