From owner-freebsd-hackers Sun Dec 17 11:19:49 2000 From owner-freebsd-hackers@FreeBSD.ORG Sun Dec 17 11:19:47 2000 Return-Path: Delivered-To: freebsd-hackers@freebsd.org Received: from smtp.attica.net.nz (mail.attica.net.nz [202.180.64.33]) by hub.freebsd.org (Postfix) with SMTP id 7D57737B400 for ; Sun, 17 Dec 2000 11:19:46 -0800 (PST) Received: (qmail 14036 invoked from network); 17 Dec 2000 19:19:33 -0000 Received: from 202-180-83-13.iff2.attica.net.nz (HELO davep200.afterswish.com) (202.180.83.13) by mail.attica.net.nz with SMTP; 17 Dec 2000 19:19:33 -0000 Message-Id: <5.0.0.25.1.20001218075649.01accb00@pop3.i4free.co.nz> X-Sender: dmpreece@pop3.i4free.co.nz X-Mailer: QUALCOMM Windows Eudora Version 5.0 Date: Mon, 18 Dec 2000 08:05:21 +1300 To: heckfordj@psi-domain.co.uk From: David Preece Subject: Re: Writing Device Drivers Cc: freebsd-hackers@freebsd.org In-Reply-To: <20001217130201.A6074@freefire.psi-domain.co.uk> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii"; format=flowed Sender: owner-freebsd-hackers@FreeBSD.ORG Precedence: bulk X-Loop: FreeBSD.ORG At 13:02 17/12/00 +0000, you wrote: >Does anyone have any good tips to get started / HowTo's, or some simple >examples >that will give me knowledge like the PC Speaker or something simple like >that? This is turning into a FAQ, but don't worry about it. The usual answer is to take one of the existing drivers and work out what it does. There's also a script for making shell drivers under /usr/share/examples/drivers. As for things like "how does DMA work?", "what exactly is an interrupt and what do I do with it?" or "what's the story with memory ranges and devices then?" then I'm afraid I can't help you there. In fact (to -hackers) this strikes me as one of the more fundamental problems of free software: I would go and write/fix some device drivers (for example the unknown phy in fxp that bothers me so much), except I can't really get a handle on how you're supposed to start on these things. Comments? URL's for IRQ101? Perhaps I should just stop whingeing and go hack with it to see what happens? (probably best). >Jamie Dave To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-hackers" in the body of the message