From owner-freebsd-questions Wed May 8 12:41: 6 2002 Delivered-To: freebsd-questions@freebsd.org Received: from mailbox-10.st1.spray.net (mailbox-10.st1.spray.net [212.78.202.110]) by hub.freebsd.org (Postfix) with ESMTP id 8ACB937B412 for ; Wed, 8 May 2002 12:40:34 -0700 (PDT) Received: from p7 ([213.33.246.102]) by mailbox-10.st1.spray.net (8.8.8/8.8.8) with SMTP id VAA01510 for ; Wed, 8 May 2002 21:40:29 +0200 (MEST) Posted-Date: Wed, 8 May 2002 21:40:29 +0200 (MEST) Message-ID: <032501c1f6c8$34094780$0100a8c0@p7> From: "AMI" To: References: <3CD93DC7.6C037CA7@is-production.com> Subject: Re: COM port for voltage command/measurement ? Date: Wed, 8 May 2002 21:52:37 +0400 MIME-Version: 1.0 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: 7bit X-Priority: 3 X-MSMail-Priority: Normal X-Mailer: Microsoft Outlook Express 5.00.2615.200 X-MimeOLE: Produced By Microsoft MimeOLE V5.00.2615.200 Sender: owner-freebsd-questions@FreeBSD.ORG Precedence: bulk List-ID: List-Archive: (Web Archive) List-Help: (List Instructions) List-Subscribe: List-Unsubscribe: X-Loop: FreeBSD.ORG Hello! I think you may use DTR as command for external relay about +12-3 V. But don't use RTS because it's info wey and haven't true voltage for. It is cheme of the connector: 9 PIN D-SUB MALE at the Computer. Pin Name Dir Description 1 CD <== Carrier Detect 2 RXD <== Receive Data 3 TXD ==> Transmit Data 4 DTR ==> Data Terminal Ready 5 GND === System Ground 6 DSR <== Data Set Ready 7 RTS ==> Request to Send 8 CTS <== Clear to Send 9 RI <== Ring Indicator Note: Direction is DTE (Computer) relative DCE (Modem). Andrew > Hi, > > I did some search on your archives and others, and found no info on that > : > > I need to use a com port to command voltage on com port pins, to be able > to drive external relays. > > Would anybody have any hint/example for that function ? > > Best regards, > -- > > __________ Bernard DUGAS ________________________________________ To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-questions" in the body of the message