It is possible to support advanced features of MO drives on the Amiga by using custom driver software. No-one has written any such software yet, but here are some things which could be done:

• Support automatic media capacity detection. So regardless of whether a 128MB, 230MB, 540MB or 640MB disk is inserted, the drive could be accessed as MO0:. This would be similar to the way that both high and low density floppy disks are supported as DFx:. The sector size can also change; it is 512 bytes for 128MB, 230MB and 540MB 3½" disks, but 2048 bytes for 640MB disks. CrossDOS and XFS have this capability for AT-HD type MO disks.
• Allow disks to be low-level formatted. Low-level formatting is possible using ExpertPrep, available from the GVP-M web site. However this does not provide full support for all features.
• Partial support for the write cache may be possible, especially in conjunction with disk cache software running on the Amiga.
• Extended error detection. Detect when the MO drive has to use its error correction circuitry or retry reading a track. This does not result in data loss, but many such occurrences may indicate that the disk or drive needs cleaning. A requester could optionally alert the user to this. The drive maintains a log of recoverable errors, and this is readable by the Amiga.
• Allow various options to be changed in software, rather than having to change a DIP switch on the drive, such as spindle automatic stop mode, write cache mode and verify mode.
• Allow other options to be set for which there are no DIP switches, such as spindle stop monitoring time and power save mode.
• Filesystems could have an option to "pre-erase" unused areas of an MO disk, to allow writing new data to normal media to be as fast as for LIMDOW media.
• Filesystems can enable or disable verification of writes on a per-partition (actually per-write) basis. This speeds up writes, and may be a good idea for partitions that contain temporary, unimportant data, such as a web browser's cache.
• A filesystem could be written to support NSR format disks, or UDF which is a subset of NSR. See the About NSR and UDF section.
• Some MO drives have their firmware in Flash ROM. This means that it is possible to update the firmware from the host computer. Software to do this exists for the PC; it would be useful to have an Amiga firmware downloader program also. An archive containing PC firmware downloader program and BIOS for Fujitsu M2513 640MB 3½" drive mechanisms is available from the Maxoptix web site. I have also created a web page which contains several firmware versions for Fujitsu and Philips OEM M2513A drives. This can be accessed from my main web page at: http://visitweb.com/mark At the time of writing, the direct URL is: http://home.freeuk.net/markk/MO/index.html

I envisage an "mo.device" being written, that goes in between the filesystem and the underlying SCSI device (scsi.device, gvpscsi.device, etc.). Multiple units of mo.device could access multiple MO drives on multiple SCSI controllers, if present. Something like this may already have been written by Fourth Level Developments. I would like to find information on their "MO-MIGA" software package.

Documentation

There is extensive documentation in PDF format for the Fujitsu M2513 and MBC3064SS/MCC3064SS 640MB 3½" SCSI and MCA3064AP IDE/ATAPI drive mechanisms available from the Fujitsu Europe web site at:

http://www.fujitsu-europe.com/

You can print the PDF files on an Amiga using Ghostscript, or run Acrobat Reader under Macintosh emulation. The direct URLs for these files are as follows.

M2513S (DynaMO 640) Maintenance Manual; 1016015 bytes, 79 pages:

http://www.fujitsu-europe.com/home/support/mo/manuals/cat4s_mm1.pdf

M2513A OEM Manual - Specifications and Installation; 4594299 bytes, 182 pages:

http://www.fujitsu-europe.com/home/support/mo/manuals/cat4_si_3.pdf

M2513A OEM Manual - SCSI Logical Specifications; 1548914 bytes, 167 pages:

http://www.fujitsu-europe.com/home/support/mo/manuals/cat4_sl_2.pdf

MCA3064AP Optical Disk Drive Product Manual; 3927852 bytes, 227 pages:

http://www.fujitsu-europe.com/home/support/mo/manuals/cat4ap_pm_1.pdf

MCB3064SS, MCC3064SS Optical Disk Drives Product Manual; 7938348 bytes, 234 pages:

http://www.fujitsu-europe.com/home/support/mo/manuals/cat4ess_pm.pdf

MCB3064AP, MCC3064AP Optical Disk Drives Product Manual; 3880565 bytes, 229 pages:

http://www.fujitsu-europe.com/home/support/mo/manuals/cat4eap_pm.pdf

If you are interested in the physical specifications of MO disks, there are some relevant ECMA standards. See the About NSR and UDF section for the URL of the ECMA web site.

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