Linux - Panasonic LF1000 Optical Disk mini HOWTO
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version 1.1 - March 29, 1996
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This file applies to PC based systems only.
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Disclaimers
============
Neither the author nor the distributors of this HOWTO are in any way
responsible for physical, financial, or moral damage incurred by following
the suggestions in this text.
Copyright
==========
The Linux Panasonic LF1000 Optical Disk mini HOWTO is copyrighted
(C) 1996 by Skip Rye. Linux HOWTO documents may be reproduced and
distributed in whole or in part, in any medium physical or electronic, as long
as this copyright notice is retained on all copies. Commercial redistribution
is allowed and encouraged. The author, however, would like to be notified
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this copyright notice. In other words, you may not produce a derivative work
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Exceptions to these rules may be granted under certain conditions. In short,
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redistribute the HOWTOs. Should you have any questions, please contact
Greg Hankins, the Linux HOWTO coordinator, at gregh@sunsite.unc.edu.
You may finger his address for phone number and additional contact
information.
Phase Change Optical Technology
================================
Optical Phase Change technology is used to create "In Phase" or "Out of
Phase" bits on a special media for phase change writing. The drive uses a
LASER of different power levels or LASER intensities to produce this
effect. One power level allows the media to flow into a crystalline form
while the other creates an "Out of Phase" condition. The crystallized areas
reflect the read Lasers beam with a different coefficient of reflectivity than
the non-crystallized areas. Thus, data can be read from the disk.
What makes the phase change optical disk special is that it the disk is
formated with concentric cylinders or tracks with each track being sectored
much like a magnetic disk or read/write optical disk. The tracks are very
close so a lot of data can be stored on a disk. This is different from a
CD-ROM in that it gives your system the look and feel of a magnetic disk.
CD-ROMs have a spiraling track much like a audio record. Having tracks
and sectors alone would not make the phase change drive special from
optical disk but the drive has some very special properties; The phase change
drive allows for direct overwrite of data which magneto optical can't do
inexpensively and the media has the very special property of NOT being
susceptible to magnetic fields or as sensitive to static discharge which gives
the media a very long shelf life.
POINTS OF INTEREST
===================
o Less than $500.
o If You already have a SCSI controller they may provide you with and
extra disk instead.
o Read/Write optical disk.
o Can read CD-ROMs at 4X speed.
o Can read Kodak PhotoCDs.
o Media has a 15 Year shelf life.
o SCSI-2 Interface.
o Track/sector format as opposed to CD-ROMs spiraling record
format.
o 165ms access time - much better than a tape file restore.
o 650Mb data storage per diskette.
o Diskettes are about $50 each.
THINGS YOU SHOULD KNOW
=======================
o It is unknown if the SCSI controller sold with the drive will work
for Linux. If you find that it or other controllers work, please
E-Mail me!
o Optical disk format not compatible with any other disk drive.
However, it does have a fair chance of being the next A drive for
PCs.
o Vendors don't seem to support UNIX very well, to bad $$$ -
marketing is targeted for DOS/Windows and Macintosh.
o It seems that the "Use LU" jumper setting works for both Linux and
DOS even though the manual for DOS says to not use LUs? So you
don't have to change jumper settings between DOS/Windows and
Linux.
Installation
=============
The LF1000 is SCSI-2 compatible device. It features a block size of 512
bytes and is compatible with the Linux SCSI drivers. This drive was
installed on a PC compatible AMD 100MHZ 486 with an Adaptic 1542C
SCSI bus-master controller. To install and mount a read/write optical disk
the following steps were taken;
Installation steps :
o Install the drive and set the SCSI address to not interfere with other
SCSI devices. Reconnect all cabling.
o Boot the computer. Your SCSI controller should note the new drive.
o During the Linux kernel boot, you should see an additional SCSI
device. In my case, having a magnetic system disk for device /dev/sda
it shows up as /dev/sdb.
o I did NOT partition the device because fdisk issued an overwrite
warning and I did not want to change anything from a dosemu
standpoint.
o mkfs -t ext2 /dev/sdb
o mkdir /pd
o mount -t ext2 -o ro,suid,dev,exec,auto,nouser,async /dev/sdb /pd -
Read only
o mount -t ext2 -o defaults /dev/sdb /pd - Mount drive W/R
Your ready to "Rock'n'Roll"
Usage hints
============
Currently it is unknown if the SCSI kernel driver will support switch-able
device modes - ie. CD-ROM ISO 9660 format and ext2 file-systems. If
someone knows please E-mail me.
When Linux boots, it should recognize your new SCSI drive? ie sda or sdb
device. Here is a cutout of the demsg command. Notice it detected the
MATSHITA drive. You should get a similar message.
Note : The three lines below "Adding Swap" line was because Linux was
booted for pd use. If a CD-ROM was in the drive at boot time the driver
would have mounted it as /cdrom using ISO 9660 format. YOU MUST
BOOT LINUX WITH A CD-ROM INSTALLED TO USE THE DRIVE
AS A CD-ROM. Once Linux is booted with a CD-ROM it is simple a
matter of doing a "umount /cdrom" to change media. The new CD-ROM
would of course have to be re-mounted. A shell is provided below to assist
you with this, just cut it out to a file say "mgrpd" and do "sh mgrpd"
#------------------------ Cut of demsg command -------------------------------
Configuring Adaptec at IO:330, IRQ 11, DMA priority 5
scsi0 : Adaptec 1542
scsi : 1 host.
Vendor: QUANTUM Model: PD1050iS Rev: 3110
Type: Direct-Access ANSI SCSI revision: 02
Detected scsi disk sda at scsi0, id 0, lun 0
Vendor: MATSHITA Model: PD-1 LF-1000 Rev: A109
Type: Optical Device ANSI SCSI revision: 02
Detected scsi disk sdb at scsi0, id 1, lun 0
scsi : detected 2 SCSI disks total.
SCSI Hardware sector size is 512 bytes on device sda
SCSI Hardware sector size is 512 bytes on device sdb
Linux version 1.2.13 (root@bigkitty) (gcc version 2.7.0) #1 Wed Aug 23 03:54:14
CDT 1995
Partition check:
sda: sda1 sda2 sda3 sda4
sdb: bad partition table
VFS: Mounted root (ext2 filesystem) read-only.
Adding Swap: 34812k swap-space
end_request: I/O error, dev 2100, sector 64
isofs_read_super: bread failed, dev 0x2100 iso_blknum 16
Unable to identify CD-ROM format.
------------------------ Cut of demsg command -------------------------------
I've got an Adaptec 1452C SCSI controller with Slackware's "scsinet1"
kernel . It works fine with that configuration. Note, if your controller is
different check the SCSI-HOWTO by Drew Eckhardt for comments.
To aid in using the LF1000 drive here is a shell. You are free to use the shell
but please keep the copyright with it.
--------------------------------- Cut Here ---------------------------------
#@/@/@ mgrpd ABR Linux 1.2.13 486 mgr shell for phase change drive
#************************************************************************#
# #
# program : mgrpd #
# #
# #
# #
# #
# Author : Skip Rye Copyright 1996 #
# #
# Revision : v1.0 02-01-96 Start #
# 03-13-96 Released #
# #
# Calls : None #
# #
# Files : #
# #
# #
########################################################################*/
# Display menu and process choice:
sel=0
while [ $sel ]
do
echo "***************************************************************"
echo "* MGRPD *"
echo "* Version v1.0, Copyright 1996, Author Skip Rye *"
echo "***************************************************************"
echo "************** ext2 formated file system *********************"
echo "1) Format pd disk - mkfs /dev/sdb"
echo "2) Mount pd read/write"
echo "3) Mount pd read only"
echo "************** dos formated file system ***********************"
echo "Note : must have been formatted using dos"
echo "4) Mount read/write"
echo "5) Mount read only"
echo "40) List disk space - df"
echo "50) umount"
echo "######################## CDROM ################################"
echo "Note : must have Use LUN Numbers jumper on drive"
echo "100) Mount CDROM"
echo "101) umount CDROM"
echo "END Hit to End"
echo
echo "Select option: \c"
read sel
case $sel in
1)
echo "This option assumes ext2 is the default mkfs format"
echo "This will DESTROY ALL data on disk. Enter y to continue."
read ans1
if [ $ans1 ]
then
echo "Enter the fully qualified path name of the PD drive"
echo "ie. /dev/sdb"
read pdpath
if [ $pdpath ]
then
if [ $ans1 = "y" -o $ans1 = "Y" ]
then
echo "This will DESTROY ALL data on disk $pdpath. Enter y to co
ntinue"
read ans2
if [ $ans2 ]
then
if [ $ans2 = "y" -o $ans2 = "Y" ]
then
mkfs $pdpath
fi
fi
fi
fi
fi
;;
2)
mount -t ext2 -o defaults /dev/sdb /pd
;;
3)
mount -t ext2 -o ro,suid,dev,exec,auto,nouser,async /dev/sdb /pd
;;
4)
mount -t msdos -o rw,suid,dev,exec,auto,nouser,async /dev/sdb /pd
;;
5)
mount -t msdos -o ro,suid,dev,exec,auto,nouser,async /dev/sdb /pd
;;
40)
df
;;
50)
umount /dev/sdb
;;
100)
/etc/rc.d/rc.cdrom
;;
101)
umount /cdrom
;;
esac
done
--------------------------------- Cut Here ---------------------------------
If things don't work consider the following;
o What kind of SCSI controller are you using? Is that controller
supported, see the SCSI-HOWTO by Drew Eckhardt.
o Is support for that controller complied in your Kernel?
o For the CD to work you need to have powered on the LF1000 and
installed a CD-ROM before you boot Linux. After that you can
switch CD's by unmounting, switching CD-ROMs and remounting
- See the "mgrpd" shell provided.
o For the read/write optical disk to work you must have booted Linux
without a CD-ROM installed in the drive.
o Is the jumper setting for the LF1000 set to use logical unit (LU)
numbers.
The media which comes with the drive is reported be re-writable about
500,000 times. This means that it is not advisable to install a live operating
system such as Linux on the phase change optical drive. These live operating
systems tend to cache processes to and from disk. Over time this can easily
approach the phase change media life.
Mount drive read only as much as possible.
When writing to the drive do so in large chunks. This will help reduce any
file fragmentation which will require more read seeks.
This is however an excellent media for backups, gifs, mpeg or storing large
programs which you don't use that often. The restore from backup is much
faster that tape. Backups can be performed using the cp -rp command
without the need for the ftape driver. This however, will replace symbolic
links with the actual file.
Author : Skip Rye root@brspc_0064.msd.ray.com