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Newsgroups: comp.unix.bsd.freebsd.misc Path: euryale.cc.adfa.oz.au!newshost.anu.edu.au!harbinger.cc.monash.edu.au!simtel!news.sprintlink.net!news.onramp.net!lerami!rwsys!rowdy.lonestar.org!nemesis!uhclem From: uhclem@nemesis.lonestar.org (Frank Durda IV) Subject: Re: Panasonic 52x CDROM support X-Newsreader: Tin 1.1 PL5 Organization: The Big Blue Box Message-ID: <DF12ux.8r@nemesis.lonestar.org> References: <434gnn$i46@fozzie.sun3.iaf.nl> Date: Sun, 17 Sep 1995 02:28:09 GMT Lines: 35 [0]uhclem@nemesis.lonestar.org (Frank Durda IV) writes: [0]When Matsushita came out with the 562/563 in 1993, they changed the command [0]sets, so the two designs are not compatible. [0] [0]So, currently there is no support under FreeBSD for the 522/523 drives. [1]Geert Bosch (geert@sun3.iaf.nl) wrote: [1]If only the command set is different, wouldn't it be easy to change [1]the 562/563 drivers to include support for the 522/523 drives? [1]Although they're old, there are a lot of them around, since they [1]were included in the original SoundBlaster 'MultiMedia' packages. The problem is that there is no documentation on what the 522/523 command set *is*. All we know is that it is different, mainly because Matsushita says so and the 562/563 DOS drivers don't work on 522/523 hardware. There may be differences in addition to the command set, such as how the commands and data transfers handshake, length of commands, timing, etc. The Creative interface is pretty stupid and without interrupts or DMA, it is up to the driver to know when it has waited "long enough". The TEAC CD55A is a similar problem. It connects to the Creative interface, but has a completely different command structure than the 562/563 (10 bytes versus 7), and the CD55A uses the control signals differently than the 562/563 drives do. (So far, it has been easier to write a separate driver for the CD55A than to try to get the 562/563 driver to work.) Also like the 522/523, the CD55A has no published command set. So a lot of effort has to go into finding out how to operate the hardware. If you have information on the 522/523 command set and precise programming details, that will help getting support added for those drives. Frank Durda IV uhclem%nemesis@fw.ast.com