From owner-freebsd-questions Fri Jun 18 1:45:20 1999 Delivered-To: freebsd-questions@freebsd.org Received: from allegro.lemis.com (allegro.lemis.com [192.109.197.134]) by hub.freebsd.org (Postfix) with ESMTP id 9DE511500D for ; Fri, 18 Jun 1999 01:45:09 -0700 (PDT) (envelope-from grog@freebie.lemis.com) Received: from freebie.lemis.com (freebie.lemis.com [192.109.197.137]) by allegro.lemis.com (8.9.1/8.9.0) with ESMTP id SAA08874; Fri, 18 Jun 1999 18:14:58 +0930 (CST) Received: (from grog@localhost) by freebie.lemis.com (8.9.3/8.9.0) id SAA03115; Fri, 18 Jun 1999 18:14:54 +0930 (CST) Date: Fri, 18 Jun 1999 18:14:53 +0930 From: Greg Lehey To: Don Read Cc: Andrew Johns , FreeBSD Questions , cjclark@home.com Subject: Re: Null-Modem? Message-ID: <19990618181452.B2863@freebie.lemis.com> References: <000f01beb948$1a080670$4001a8c0@tasajohns.turnaround.com.au> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii X-Mailer: Mutt 0.95.4i In-Reply-To: ; from Don Read on Fri, Jun 18, 1999 at 01:21:43AM -0500 WWW-Home-Page: http://www.lemis.com/~grog X-PGP-Fingerprint: 6B 7B C3 8C 61 CD 54 AF 13 24 52 F8 6D A4 95 EF Organization: LEMIS, PO Box 460, Echunga SA 5153, Australia Phone: +61-8-8388-8286 Fax: +61-8-8388-8725 Mobile: +61-41-739-7062 Sender: owner-freebsd-questions@FreeBSD.ORG Precedence: bulk X-Loop: FreeBSD.ORG On Friday, 18 June 1999 at 1:21:43 -0500, Don Read wrote: > > On 18-Jun-99 Andrew Johns wrote: >> A null-modem cable is a cable with the correct wires crossed/joined - >> typically if all you want is software flow control (not the best but it >> works) just connect pins 2,3 and 7 in a DB25 serial port connector (aka >> V35 connector) and swap pins 2 and 3 at one end. Pin 2 is transmit, 3 >> receive, 7 ground; so you've got: >> >> One end: Other end: >> >> TX 2 --------\/------------- 3 RX >> RX 3 --------/\------------- 2 TX >> Gr 7 ----------------------- 7 Ground >> > if your terminals pay attention to the control signals then add: > > RTS 4 -- -- 4 > | | > CTS 5 -- -- 5 > > DSR 6 -- -- 6 > | | > CD 8 -- -- 8 > | | > DTR 20 -- -- 20 Right. That's what I call a null modem. Greg -- When replying to this message, please copy the original recipients. For more information, see http://www.lemis.com/questions.html See complete headers for address, home page and phone numbers finger grog@lemis.com for PGP public key To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-questions" in the body of the message