From owner-freebsd-hackers Wed Aug 27 07:00:52 1997 Return-Path: Received: (from root@localhost) by hub.freebsd.org (8.8.7/8.8.7) id HAA04903 for hackers-outgoing; Wed, 27 Aug 1997 07:00:52 -0700 (PDT) Received: from earth.mat.net (root@earth.mat.net [206.246.122.2]) by hub.freebsd.org (8.8.7/8.8.7) with ESMTP id HAA04898 for ; Wed, 27 Aug 1997 07:00:44 -0700 (PDT) Received: from Journey2.mat.net (journey2.mat.net [206.246.122.116]) by earth.mat.net (8.8.7/8.6.12) with SMTP id JAA07929; Wed, 27 Aug 1997 09:59:36 -0400 (EDT) Date: Wed, 27 Aug 1997 09:59:35 -0400 (EDT) From: Chuck Robey X-Sender: chuckr@Journey2.mat.net To: Adam Baran cc: freebsd-hackers@FreeBSD.ORG Subject: Re: SIO driver question In-Reply-To: Message-ID: MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: owner-freebsd-hackers@FreeBSD.ORG X-Loop: FreeBSD.org Precedence: bulk On Wed, 27 Aug 1997, Adam Baran wrote: > Hi, > > Here is my question: > Is it possible to configure (or hack ;)) SIO driver to make it work with > COM2 and COM4 devices occupying the same IRQ line (namely IRQ3) ??? > > Background: > I use mouse on COM1, baseband modem on leased line on COM2 (to ISP). > COM1 and COM2 are motherboard builtin COMs. > I'd like also to configure internal ZOOM FCV9425 modem to work as callin > device. Problem is that I can only jumper the modem to occupy specific COM > port (namely 1,2,3 or 4) but can't change IRQ beyond defaults. > > So, maybe someone could help me with SIO configuration or simply tell: > "this is impossible'. If you're talking about getting two serial devices to cooperate in sharing the same interrupt, no, it's not possible without a card specifically designed for that sharing, like a Digiboard or Boca card. Basically, the ISA bus doesn't allow sharing of IRQ's. It works on dos because the other ports aren't actually hooked up to executing code when you aren't using them, but on Unix of any kind, they are all hooked up to executing drivers at all times, and you cannot share irq's. You get folks once in a while, even on this list, who claim it isn't so. These are the same people who claim there's no reason why their sound cards or printer ports don't work correctly (whatever they've purposely or inadvertently shared). > > Thanks in advance. > > > > ----------------------------+----------------------------------------------- Chuck Robey | Interests include any kind of voice or data chuckr@eng.umd.edu | communications topic, C programming, and Unix. 213 Lakeside Drive Apt T-1 | Greenbelt, MD 20770 | I run Journey2 and picnic, both FreeBSD (301) 220-2114 | version 3.0 current -- and great FUN! ----------------------------+-----------------------------------------------