From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mailserv2.iuinc.com (qmailr@mailserv2.iuinc.com [206.245.164.55]) by puffin.external.hp.com (8.8.7/8.8.7) with SMTP id VAA24983 for ; Mon, 29 Nov 1999 21:16:03 -0700 Received: from storm.ca (dial01p40.ottawa.storm.ca [209.87.225.40]) by mail.storm.ca (8.8.8+Sun/8.8.8) with ESMTP id XAA18880 for ; Mon, 29 Nov 1999 23:17:53 -0500 (EST) Message-ID: <38430939.435033DA@storm.ca> Date: Mon, 29 Nov 1999 23:16:09 +0000 From: Sandy Harris MIME-Version: 1.0 To: parisc-linux@thepuffingroup.com Subject: Re: [parisc-linux] Parallel port hardware (fwd) References: <199911291708.JAA10386@meow.sr.hp.com> Content-Type: text/plain; charset=us-ascii List-ID: "Bill Katz (William)" wrote: > Sandy Harris wrote: > |Can anyone point me to info on the electrical properties of the parallel ports > |on 712 or 715 machines? > | > |I'm thinking that 8 715s might make an interesting parallel engine, but the cable device > |only works if the parallel port's control lines are implemented as open collector TTL. > |Where can I discover whether they are? > > Early 715s ... > > Later 715s (/64, /80, /100) and all 712s use Lasi. From the chip ERS > (not published, it's mostly electrical stuff) Data strobe, autofeed, > parinit, and select > > The ones that connect to pins 1, 14, 16, and 17 are open collector. Bingo! Those are exactly the four lines used for the Wapers parallel stuff. http://garage.ecn.purdue.edu/~papers/WAPERS/