Re: Still Having Fun with SCSI Emulation.

["Martin G. McCormick" <martin@dc.cis.okstate.edu>]

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	I made a lot of progress and what I found may help some
people so here it is as briefly as I can make it.

	First, I will sound like a politician here and say that
everybody was right to some extent on configuring SCSI emulation
in the kernel.  My big mistake was in compiling in SCSI disk
support.  This killed the CDROM SCSI emulation.  When I took out
the SCSI disk support, the SCSI channel appeared.

	I still had terrible problems with cdda2wav and
cdparanoia and they both did the same thing.

	Both tried to work using /dev/scd0 as the scsi device,
but the system groaned and sputtered and the audio was full of a
wraspy sound which was basically a break in the sound about 75
times per second.  This is the sector rate, but you shouldn't
hear it.  I ran cdparanoia for 20 or 30 minutes once and it
didn't even rip one song completely.

	Since I now had SCSI emulation, I decided to install the
Plextor CDRW drive.  I guess the other drive is simply not
capable of CDDA playback because the system now can download an
entire CD in 7 minutes flawlessly with perfect audio just like it
is supposed to.

	Both cdda2wav and cdparanoia now seem to work perfectly
but I seem to still be snatching defeat from the jaws of victory.

	It was time to burn a CDRW disk with a file system so I
put in a brand new CDRW which was included with the drive as a
sample.
I got mkisofs to produce a mountable image so the last step was
to feed that to cdrecord.  I used the following command.

mkisofs -l -R -q /home/martin |cdrecord -dev=/dev/scd0:0,0 -dummy -

	I held my breath and got the following error which was
the first error I had seen using the new drive:

cdrecord: Cannot do inquiry for CD/DVD-Recorder.
cdrecord: Success. test unit ready: scsi sendcmd: fatal error
Cdrecord 1.8 (i686-pc-linux-gnu) Copyright (C) 1995-2000 Jörg Schilling
scsidev: '/dev/scd0:0,0'
devname: '/dev/scd0'
scsibus: 0 target: 0 lun: 0
Using libscg version 'schily-0.1'
CDB:  00 00 00 00 00 00
cmd finished after 0.000s timeout 40s

	The order of the output lines from cdrecord is a little
different than they normally display, but I captured standard
error and standard output and they don't arrive at the same time.
If I use cdparanoia and test the drive, I get good output

cdparanoia III release 9.7 (December 13, 1999)
(C) 1999 Monty <monty@xiph.org> and Xiphophorus

Checking /dev/sg0 for cdrom...
	Testing /dev/sg0 for cooked ioctl() interface
		/dev/sg0 is not a cooked ioctl CDROM.
	Testing /dev/sg0 for SCSI interface
		generic device: /dev/sg0
		ioctl device: /dev/scd0
		CDROM sensed: PLEXTOR CD-R   PX-W1210A 1.08 

Checking for SCSI emulation and transport revision...
	Drive is ATAPI (using SCSI host adaptor emulation)

Checking for MMC style command set...
	Drive is MMC style
004: Unable to read table of contents header

Unable to open disc.  Is there an audio CD in the drive?

	That last part about the audio CD is due to there being
the new CDRW which had not yet been recorded yet.  If I put an
audio CD in, it reads the table of contents just fine.

	Has anybody any ideas as to what this last nasty problem
is?

	By the way, if you compile the SCSI emulation support in
to the kernel, the append statements in lilo.conf don't seem to
do anything.  That probably is necessary to make the module load,
but I tried it with and without and nothing changed.

	Thanks to Janina and all for your good suggestions.  You
have kept me beating my head on this brick wall until I have made
a dent at least.  I'm still not all the way through, yet.
Martin McCormick