I am having trouble getting my CD-ROM working on a IIvi running
NetBSD 1.3.3 (GENERICSBC).  My system setup is:
SCSI ID 0: internal 230 meg Quantum hard disk (only MacOS, no BSD partitions)
SCSI ID 1: external 1 gig Micropolis hard disk (MacOS partition, NetBSD root partition, NetBSD usr partition)
SCSI ID 3: internal Sony CD-ROM 2x speed
There is a ribbon cable going from the board to the CD-ROM and then to
the Quantum drive.
Initially the machine wouldn't mount the CD at all.  I opened the case
and took off the parity jumper from the CD-ROM and now the mounting
is sporadic.  Sometimes it mounts, sometimes not.  I always get lots
of error messages concerning the CD which I list below.  The CD I am
trying to mount is a NetBSD distribution disk in hybrid format.  When
I can mount the CD, I only see the directories at the top level.
Going into the packages directory I cannot 'ls' the files there.
'cd ..' will not return me to the parent directory either.  But 'cd /'
does return me to the root directory.  That said, here is abrieviated
output from 'dmesg'.
====================================================================
NetBSD 1.3.3 (GENERICSBC) #0:  Thu  Dec 17 09:12:26 CST 1998
    scottr@fx1:/usr/src/sys/arch/mac68k/compile/GENERICSBC
Apple Macintosh IIvi  (68030)
...
sbc0: parity error! (2 times)
sbc0: Target 3 LUN 0 stuck busy, resetting...
sbc0: parity error! (4 times)
sbc0: Target 3 LUN 0 stuck busy, resetting...
sbc0: parity error! (2 times)
sbc0: unexpected MESSAGE OUT; sending NOOP
sbc0: parity error! (6 times)
sbc0: unexpected MESSAGE OUT; sending NOOP
cd0 at scsibus0 targ 3 lun 0: (SONY, CD-ROM CDU-8003A, 1.8f) SCSI2 5/cdrom removable
...
/dev/sd1g: file system not clean; please fsck(8)
sbc0: parity error! (2 times)
sbc0: Target 3 LUN 0 stuck busy, resetting...
sbc0: parity error! (4 times)
sbc0: Target 3 LUN 0 stuck busy, resetting..
sbc0: parity error! (2 times)
sbc0: unexpected MESSAGE OUT; sending NOOP
sbc0: parity error! (8 times)
sbc0: unexpected MESSAGE OUT; sending NOOP
sbc0: parity error! (2 times)
sbc0: Target 3 LUN 0 stuck busy, resetting...
sbc0: parity error! (4 times)
sbc0: Target 3 LUN 0 stuck busy, resetting...
sbc0: parity error! (6 times)
sbc0: Target 3 LUN 0 stuck busy, resetting...
sbc0: parity error! (6 times)
sbc0: Target 3 LUN 0 stuck busy, resetting...
sbc0: parity error! (4 times)
cd0(sbc0:3:0): unit attention, data = 00 00 00 00 29 00 00 00 00 00
sbc0: parity error! (2 times)
/dev/sd1g: file system not clean; please fsck(8)
============================= end of dmesg =========================

I appreciate any help that may correct this situation.  Thanks in advance.

Patrick