From owner-freebsd-hardware Tue Aug 20 19:39:27 1996 Return-Path: owner-hardware Received: (from root@localhost) by freefall.freebsd.org (8.7.5/8.7.3) id TAA00207 for hardware-outgoing; Tue, 20 Aug 1996 19:39:27 -0700 (PDT) Received: from genesis.atrad.adelaide.edu.au (genesis.atrad.adelaide.edu.au [129.127.96.120]) by freefall.freebsd.org (8.7.5/8.7.3) with ESMTP id TAA00180 for ; Tue, 20 Aug 1996 19:39:19 -0700 (PDT) Received: from msmith@localhost by genesis.atrad.adelaide.edu.au (8.6.12/8.6.9) id LAA08586; Wed, 21 Aug 1996 11:52:29 +0930 From: Michael Smith Message-Id: <199608210222.LAA08586@genesis.atrad.adelaide.edu.au> Subject: Re: ASUS SC200 SCSI card? (PCI interrupts) To: gtc@aloft.att.com (gary.corcoran) Date: Wed, 21 Aug 1996 11:52:28 +0930 (CST) Cc: msmith@atrad.adelaide.edu.au, freebsd-hardware@FreeBSD.org In-Reply-To: <9608210204.AA12263@stargazer> from "gary.corcoran" at Aug 20, 96 10:04:20 pm MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: owner-hardware@FreeBSD.org X-Loop: FreeBSD.org Precedence: bulk gary.corcoran stands accused of saying: > > >PCI interrupts are lettered (INTA, INTB, INTC, INTD), not numbered, and > >that INTA on one slot is _NOT_ connected to INTA on any other slot. > > Is the non-connection between same-letter PCI interrupts in different > slots only on good (versatile) motherboards, or is that part of the > PCI spec? I was under the impression that at least _some_ MBs shared > their PCI interrupts...? The normal convention with PC motherboards is that devices will normally only generate INTA, and that INTA on each slot is routed seperately. Beyond this, I'm not so sure. I believe that other interrupts can be used by PCI-PCI bridge chips, but I'm not clear on that. Certainly there have been some motherboards where INTA was bridged across several slots; these all fall into the 'very broken' category. > Gary -- ]] Mike Smith, Software Engineer msmith@atrad.adelaide.edu.au [[ ]] Genesis Software genesis@atrad.adelaide.edu.au [[ ]] High-speed data acquisition and (GSM mobile) 0411-222-496 [[ ]] realtime instrument control (ph/fax) +61-8-267-3039 [[ ]] Collector of old Unix hardware. "Where are your PEZ?" The Tick [[