From owner-freebsd-hardware Fri Sep 5 21:15:33 1997 Return-Path: Received: (from root@localhost) by hub.freebsd.org (8.8.7/8.8.7) id VAA19502 for hardware-outgoing; Fri, 5 Sep 1997 21:15:33 -0700 (PDT) Received: from bob.tri-lakes.net ([207.3.81.6]) by hub.freebsd.org (8.8.7/8.8.7) with SMTP id VAA19495 for ; Fri, 5 Sep 1997 21:15:27 -0700 (PDT) Received: from [207.3.81.149] by bob.tri-lakes.net (NTMail 3.02.13) with ESMTP id ra266751 for ; Fri, 5 Sep 1997 23:15:27 -0500 Message-ID: X-Mailer: XFMail 1.1 [p0] on FreeBSD Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 8bit MIME-Version: 1.0 Date: Fri, 05 Sep 1997 21:29:46 -0000 (GMT) From: Chris Dillon To: freebsd-hardware@freebsd.org Subject: Tape geometries for the floppy-tape driver Sender: owner-freebsd-hardware@freebsd.org X-Loop: FreeBSD.org Precedence: bulk I notice that FreeBSD's ft driver has been stagnant for some time. I noticed this when trying to use some 2120EX and 2120XL tapes in my HP Colorado Jumbo 350. Apparently the standard 2120 tapes work fine, but /usr/src/sys/i386/isa/ft.c lists a very short and incomplete tape geometry table (a whole 6 tapes!). My attempts to find the geometries of these new, larger tapes has been fruitless so far (I'm assuming thats all I need to get these tapes to work). I've managed to figure out what some of the fields mean in the geometry table, but not all of them. Correct me if I'm wrong, but here is what I gather the table represents, for example: { 2, 2, "QIC-80", "307.5/550", 28, 150, 4800, 128, 19200 }, This is a standard DC2120 250MB compressed tape. First two fields just seem to be some kind of ID tag internal to the driver. The "307.5" is tape length in feet, and the 550 is the tape coercivity in oersteds. The next field is the number of serpentine tracks on the tape. The remainder of the fields elude me. 19200 could possibly be bits/inch, but i think it is supposed to be 14700 for this particular tape. Web index searches on the subject of tape geometries didn't get me much. I found the geometries of the DC2120 and DC2120XL tapes, and thats it. Basically, the whole point of all this hot air was to ask for some help in adding new geometries to the tape table. Actually.. anyone have any idea how hard it would be to port the Linux floppy-tape driver over? (I have no clue how to do so or I would have started already ) It looks almost as if it auto-adapts to any tape size as it has no geometry table. If it did, I would have already copied the relevant data from it. :( --- Chris Dillon --- cdillon@tri-lakes.net --- Powered by FreeBSD, the best free OS on the planet ---- (http://www.freebsd.org)