From owner-freebsd-hackers Mon Sep 6 0:11:55 1999 Delivered-To: freebsd-hackers@freebsd.org Received: from mrelay.jrc.it (mrelay.jrc.it [139.191.1.65]) by hub.freebsd.org (Postfix) with ESMTP id DF4A91508E for ; Mon, 6 Sep 1999 00:11:52 -0700 (PDT) (envelope-from nick.hibma@jrc.it) Received: from elect8 (elect8.jrc.it [139.191.71.152]) by mrelay.jrc.it (LMC5692) with ESMTP id JAA12022; Mon, 6 Sep 1999 09:11:06 +0200 (MET DST) Date: Mon, 6 Sep 1999 09:11:06 +0200 (MET DST) From: Nick Hibma X-Sender: n_hibma@elect8 Reply-To: Nick Hibma To: Warner Losh Cc: Andrew Reilly , hackers@FreeBSD.ORG Subject: Re: Limit of bus hierarchies (was Re: PCI modems do not work???) In-Reply-To: <199909060541.XAA03034@harmony.village.org> Message-ID: MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: owner-freebsd-hackers@FreeBSD.ORG Precedence: bulk X-Loop: FreeBSD.ORG > No. The Windows world presents a standard SERIAL DRIVER interface, at > least that's the theory that is preached. I see no reason why a USB > serial port wouldn't do the same. USB defines a serial port > interface, IIRC, which is the same across manufacturers (in theory) > which would be handled by a single USB driver in our USB stack. Keep dreaming ... Example: Mice and keyboards have a well defined standard interface: HID (Human Interface Devices), but we have found already three ways of doing things, requiring a rewrite of the probe and attach functionality. Reason: It's much cheaper to present one device with a special interface and write the driver (for Windows) for it, than to present two functions and having to integrate a hub on the device. You don't want to know what a ethernet/parallel/serial/hub thingie looks like. I don't have one, so anyone that has one, could you send me the output of the usb_dump utility avaible from http://www.etla.net/~n_hibma/usb/usb.pl > Likewise with parallel ports. Although turning a USB parallel port > into a bit twiddling interface may present some interesting > challanges. There is at least a spec for the parallel port devices. -- ISIS/STA, T.P.270, Joint Research Centre, 21020 Ispra, Italy To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-hackers" in the body of the message