From owner-freebsd-small Thu Jun 29 18:23: 4 2000 Delivered-To: freebsd-small@freebsd.org Received: from workhorse.iMach.com (workhorse.iMach.com [206.127.77.89]) by hub.freebsd.org (Postfix) with ESMTP id EC95A37B5C4 for ; Thu, 29 Jun 2000 18:23:01 -0700 (PDT) (envelope-from forrestc@imach.com) Received: from localhost (forrestc@localhost) by workhorse.iMach.com (8.9.3/8.9.3) with ESMTP id SAA06081; Thu, 29 Jun 2000 18:23:52 -0600 (MDT) Date: Thu, 29 Jun 2000 18:23:51 -0600 (MDT) From: "Forrest W. Christian" To: Brandon Fosdick Cc: freebsd-small@FreeBSD.ORG Subject: Re: OT: Embedded system suggestions In-Reply-To: <395BE8B2.176EE0F3@glue.umd.edu> Message-ID: MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: owner-freebsd-small@FreeBSD.ORG Precedence: bulk X-Loop: FreeBSD.ORG On Thu, 29 Jun 2000, Brandon Fosdick wrote: > I was thinking about 3, 48 line digital input boards (don't know where to get > those) and maybe some digital output boards that can drive relays. Where do I > find this stuff? Does it even exist? What kind of processors do I use? What kind > of power supply do these systems need? If you're really clued, you can build these yourself. I personally would probably do something with some PIC processors on a serial port or alternatively something slightly less complicated (programming-wise) parallel port or ISA based. (Or if you'd like someone to build it for you or need more details send me e-mail off-list) Regardless, this exists commercially and is generally rather expensive. I would be looking in the latest issue of Nuts and Volts and/or Processor if I was to buy. Just Curious, is there a reason you are going the relay route as opposed to the X10 route? > I found a 216 line DIO board at www.icsadvent.com but it can't drive inductive > loads (i.e.. the relays). If all else fails I'll use this board and just make a > separate board with diodes and resistors for the relays. Inductive load = motor, Inductive load != relay. You will want to put a diode across the coil of the relay to nail any spikes. 1N914's seem to work although seem a little light at times, 1n400x's are probably better to handle the spike but are slower. If given the choice, I'd probably use the 914's (available and any radio shack). - Forrest W. Christian (forrestc@imach.com) AC7DE ---------------------------------------------------------------------- iMach, Ltd., P.O. Box 5749, Helena, MT 59604 http://www.imach.com Solutions for your high-tech problems. (406)-442-6648 ---------------------------------------------------------------------- To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-small" in the body of the message