From owner-freebsd-hackers Wed Dec 2 17:09:44 1998 Return-Path: Received: (from majordom@localhost) by hub.freebsd.org (8.8.8/8.8.8) id RAA02978 for freebsd-hackers-outgoing; Wed, 2 Dec 1998 17:09:44 -0800 (PST) (envelope-from owner-freebsd-hackers@FreeBSD.ORG) Received: from dingo.cdrom.com (ppp10.portal.net.au [202.12.71.110]) by hub.freebsd.org (8.8.8/8.8.8) with ESMTP id RAA02970 for ; Wed, 2 Dec 1998 17:09:39 -0800 (PST) (envelope-from mike@dingo.cdrom.com) Received: from dingo.cdrom.com (localhost [127.0.0.1]) by dingo.cdrom.com (8.9.1/8.8.8) with ESMTP id RAA01131; Wed, 2 Dec 1998 17:00:08 -0800 (PST) (envelope-from mike@dingo.cdrom.com) Message-Id: <199812030100.RAA01131@dingo.cdrom.com> X-Mailer: exmh version 2.0.2 2/24/98 To: zhihuizhang cc: hackers Subject: Re: Interrupt handler and interrupt unit? In-reply-to: Your message of "Wed, 02 Dec 1998 11:19:03 EST." Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Date: Wed, 02 Dec 1998 17:00:07 -0800 From: Mike Smith Sender: owner-freebsd-hackers@FreeBSD.ORG Precedence: bulk X-Loop: FreeBSD.ORG > > In the source code isa.c, I find the definition of intr_unit[]. I have no > idea what is an interrupt unit and how it is used. Maybe it refers to one > of several device units connected by a single controller and that > controller is assigned one IRQ by OS or hardware jumpers? It's the saved unit number that's passed to the interrupt handler when invoked. > Also, I want to know what specific information is passed to the system > when an interrupt occurs. I read in a book on device driver, it only says > this is OS and hardware dependent. Which part of the system? The general practice is that the hardware ultimately forwards an identifier for the interrupt number; everything else is determined from that. -- \\ Sometimes you're ahead, \\ Mike Smith \\ sometimes you're behind. \\ mike@smith.net.au \\ The race is long, and in the \\ msmith@freebsd.org \\ end it's only with yourself. \\ msmith@cdrom.com To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-hackers" in the body of the message