From owner-freebsd-current Sun Jan 3 13:10:22 1999 Return-Path: Received: (from majordom@localhost) by hub.freebsd.org (8.8.8/8.8.8) id NAA08107 for freebsd-current-outgoing; Sun, 3 Jan 1999 13:10:22 -0800 (PST) (envelope-from owner-freebsd-current@FreeBSD.ORG) Received: from hda.hda.com (hda-bicnet.bicnet.net [209.244.238.132] (may be forged)) by hub.freebsd.org (8.8.8/8.8.8) with ESMTP id NAA08102 for ; Sun, 3 Jan 1999 13:10:20 -0800 (PST) (envelope-from dufault@hda.hda.com) Received: (from dufault@localhost) by hda.hda.com (8.8.5/8.8.5) id QAA21190; Sun, 3 Jan 1999 16:06:23 -0500 (EST) From: Peter Dufault Message-Id: <199901032106.QAA21190@hda.hda.com> Subject: Re: if_ep probe failures related to reading back settings In-Reply-To: <199901032057.MAA07373@dingo.cdrom.com> from Mike Smith at "Jan 3, 99 12:56:59 pm" To: mike@smith.net.au (Mike Smith) Date: Sun, 3 Jan 1999 16:06:23 -0500 (EST) Cc: dufault@hda.com, current@FreeBSD.ORG X-Mailer: ELM [version 2.4ME+ PL25 (25)] MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: owner-freebsd-current@FreeBSD.ORG Precedence: bulk X-Loop: FreeBSD.ORG > > I have trouble properly reading the settings back from a 3C509 on > > a 180MHz Cyrix MediaGX crash box. The result is that it won't > > always probe in at boot. > > > > I find that by increasing the DELAY by a factor of 10 and more > > importantly adding a delay before reading each serial bit of data > > (I assume we're reading back a serial EEPROM): > ... > > Can someone check if we may be violating timings on reading that > > serial bus, or is it likely that this Cyrix has an inw that is too > > fast and I have to monkey with some BIOS settings? > > If Bill Paul can't help you (I think he has the '509 documentation), > then I would just bump the delays and be done with it. I don't see > reading it too slowly as being a problem, and erring on the side of > caution is always desirable. I could do that, but since this is the only ISA card I have on this thing and I'm unlikely to add any others it may not help anyone other than me and it may miss general problems with the Cyrix. I'll wait to hear if it makes sense that the delay be moved inside the loop. Then the "times 10" doesn't bother me one bit if it is used only during probe. Peter -- Peter Dufault (dufault@hda.com) Realtime development, Machine control, HD Associates, Inc. Safety critical systems, Agency approval To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-current" in the body of the message