Baslinux mailing list

["Anthony J. Albert" <albert AT polaris.umpi.maine.edu>]

On 18 May 2004 at 8:04, 3aoo-cvfd AT dea.spamcon.org wrote:
>Lamotkin AT softhome.net wrote:
>>
>> hda: QUANTUM TRB850A, ATA DISK drive
>> hdc: CD-58E, ATAPI CDROM drive
>> hdd: FUJITSU MCC3064AP, ATAPI OPTICAL drive
>
>There is your drive.  The kernel sees it on /dev/hdd.
>Everything OK so far.
>
>> /<#>mount /dev/hdd /MO
>> hdd: driver not present
>
>Ah, there's your problem.  The kernel doesn't know how
>to deal with an ATAPI OPTICAL drive.  What the hell is
>an optical drive anyway?  Is it the same as an ATAPI 
>CDROM drive?

This is more precisely a magneto-optical drive, a pretty nifty device 
that came out back in the late 1980s, before CD-ROM, I believe.   The 
idea was to take a disk and embed a layer of magneto-optical material 
between two layers of plastic.   The m-o material could be read 
optically, like a CD-ROM or DVD is read.  However, when you wanted to 
write a bit, you would use a higher-power laser to heat the m-o 
material inside the disk, then apply a magnetic field to change the 
reflectivity of the m-o substance.

This made for disks which look like thick CD-ROMs, but which can be 
read and written randomly, anytime, unlike CD-R or CD-RW.  Most systems 
treat it as a removable media drive, like a ZIP drive or other such.

However, the technology never really took off for home use.  Disk 
capacities peaked out at 1 to 2GB per double-sided disk, and the price 
per disk never really dropped, staying at about $20/GB   They also 
weren't terribly fast.  Read speeds are approximately that of 4x CD-
ROM, but writes are slow, about 1x, if that.

Barring acceptance in the home, the drives & media aren't terribly 
common.  The place that you see them most is in publishing, where they 
are still used for shipping large files around, though admittedly many 
of those are now going on CD-ROM, if they're small enough, and DVD-R 
will likely replace both before long.

I've got a 1.2GB unit with a SCSI interface, and a few disks, which 
I've been using off and on for backup.  Works well, the disk shelf life 
appears to be good (going on 10 years for some disks I have), but I've 
never run it under Linux - strictly DOS/Windows.   Under DOS, I needed 
drivers, but under Windows 95/98, it was detected and worked fine 
without additional drivers.

Hope this helps,
Anthony Albert
===========================================================
Anthony J. Albert                     albert AT umpi.maine.edu
Systems and Software Support Specialist          Postmaster
Computer Services - University of Maine, Presque Isle
        "This is only temporary, unless it works."
                        --- Red Green