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Software for writing to MO WORM discs?

Chuck(G) said:
I learned a lot from the Optisys Optidisc software reverse-engineering (PC only). A sector can have two states-written or unwritten. So when you're updating a WORM drive, you pre-allocate areas on the disc, including space for any allocation tables, search for the first unwritten sector and write the new copy of the allocation map there. Same for directories--multiple copies. It's very strange, but probably the best way to handle the issue. All of this means that you need special drivers and software to deal with a WORM, unless it's all written at once, like a CD-R.
Allocation tables, directories, file areas, of course, can have overflow areas allocated.
The WORM optical media that I dealt with was scarcely faster than a floppy disk in terms of access time, which meant that updating was slow--and if an update failed because of hardware error, the only real option was to trash the disc and start over--I ran into a few of those.
Of course, this being WORM, means that regressing updates is easy--nothing ever goes away.

I mostly think of ADIC as marketing tape drives and software. I think I still have an old ADIC quarter-inch drive here; takes DC300-sized Iotamat format cartridges. Uses a MC6800 as a controller. ADIC was big in backup solutions, particularly for the financial sector.
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I think something akin to packet writing for CDR media will apply to the WORM discs. Back in the day, a system extension (like a DOS TSR) allowed the drive to function as a read/write device. It appeared no different than a floppy disk or hard disk, in that it was writable from the Finder, and showed available free space. Deleting a file simply marked the file deleted by the file system, and it re-wrote the contents of the directory each time. So if you wrote a 100Kb file, it had to update the file system, so larger than 100Kb was written. When you deleted that same file, you didn't gain the 100+Kb and in fact, you lost more space, because the directory was re-written again.

I would expect a WORM on the Macintosh to operate this same way. Again, thanks for pointing me in the direction of MacinStor and related products. I think that may be the answer, or at least help to point us in the right direction. When I receive my media in the mail, I'll be able to confirm more. The fact that this information isn't easily available or searchable on the internet disturbs me, and I hope that posting about in forums allows people in the future to find the answers they need.
 
WORM media was expensive and the drives were slow, with the obvious limitations of being write-once. Long-term, I'm not convinced that they were any more durable than tape--and there were no standards for them. You can't, for example, use Panasonic media in non-Panasonic drives, etc.
I can see where the appeal for archival storage was real, but you had to be careful to preserve the software that handled them. That was the case for the job I did for a customer with the WORM media--there was, apparently, no move to save the software that wrote them. Eventually a QIC (3M Magnus) turned up with the software for W2K, but by that time, I'd already cracked the scheme and extracted files. The QIC tape's tension band, of course, had disintegrated, so I had to replace that one and eventually extracted the software.

Life in the slow lane--last week I received a question from a potential client: "Do you handle LTO tapes--and can you handle paper tape?"...
 
There was plenty of proprietary software during the QIC tape era you needed to keep or else, and also compression cards that made life difficult.

W2K made life easier because people just used the included Microsoft backup software, and you just needed a driver for the tape drive itself.
 
The copy of FormatterOne Pro I have is listed as version 1.4 from 1995. The Windows version is 1.6.

I know that some of the write only magneto-optical disk formats could be shared between manufacturers and I tried my best to encourage use of those instead of the proprietary formats that stored slightly more. I hadn't expected that new drives would drop support for older formats as fast as they did. It isn't much good having a disk with a 100 year expected life span if the last drive that supported the disk was made 80 years before.
 
krebizfan said:
The copy of FormatterOne Pro I have is listed as version 1.4 from 1995. The Windows version is 1.6.

I know that some of the write only magneto-optical disk formats could be shared between manufacturers and I tried my best to encourage use of those instead of the proprietary formats that stored slightly more. I hadn't expected that new drives would drop support for older formats as fast as they did. It isn't much good having a disk with a 100 year expected life span if the last drive that supported the disk was made 80 years before.
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MacintoshGarden has version 2.2.2.

Are you able to make a disk image of that 1.4 version and upload to MacintoshGarden?

I found a copy of 2.1.9 on eBay and purchased it this weekend, which I plan to archive and upload.

Sometimes older versions work better under certain circumstances and conditions.
 
Chuck(G) said:
Have you looked at Corel SCSI for Mac? ISTR there was a software driver for optical drives. Also, an outfit called LoDown offered software for Mac WORM drives. I'll keep checking...
Pinnacle Micro claimed to have software for Mac for its optical drives. The software that I was thinking of when we started this adventure was from Optisys, but apparently they concentrated on the x86 crowd. I don't know if they ever produced MacOS software.
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I found a copy of Pinnacle Micro software:

 
I wonder if Disk Copy 6.x will work for that purpose. Create a 2GB disk image with all your stuff, then write it to the WORM disk.
 
olePigeon said:
I wonder if Disk Copy 6.x will work for that purpose. Create a 2GB disk image with all your stuff, then write it to the WORM disk.
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Once I get an understanding of how all of this works, I will definitely try making a disk image using Disk Copy and writing it out to the WORM on a G5 on Mac OS X Tiger 10.4.11 and see how that performs. I do have a dual core 2.3Ghz G5 with PCI-E slots and a SCSI card that works. Hopefully it will work well with my SCSI MO drives.

The good news is my WORM media has arrived at my post office, which I can pickup on Wednesday (I’m 70 miles away!). Bad news is I only have until mid October to really test this, until likely January (as I am going away for work for a whole month).
 
Chuck(G) said:
I don't know what media you're getting, but do be aware that a lot of MO media doesn't use 512 byte sector length; 1K and 4K is quite common.
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I have a box of HP C7983A Rewritable 9.1GB Magneto Optical Cartridges, which are 4096 bytes/sector.

I purchased a batch of Lynn Medical AccuWrite 2.6Gb CCW WORM Optical Disks - P/N# 93885, which are 1024 bytes/sector. They are supposed to be compatible with the two MO drives I have: Sony RMO-S561 and HP SureStore Optical 9100mx.
 
It's not the drives, but if you're going to treat the MOs as regular HFS+ volumes, non-512 byte sectors may throw Mac OS for a loop. Dunno, never tested that on my Performas.
 
Chuck(G) said:
It's not the drives, but if you're going to treat the MOs as regular HFS+ volumes, non-512 byte sectors may throw Mac OS for a loop. Dunno, never tested that on my Performas.
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I already successfully created regular HFS volumes on the 4.3GB side (formatted capacity) of the 9.1GB Disc, using my Macintosh LC475 (68040 with SCSI Manager 4.3). It formats, mounts, reads and writes just fine under Mac OS 7.5.5 and 7.6.1.

Edit: I also created an HFS+ volume on my G3 using Mac OS 9.2.2, and it worked just fine as well.
 
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The caveat on 68k Macs is that the disk driver, and the first partition, must reside within the first 1.99GB of the disk, in order to be bootable. This also affects support for mounting on pre-68040 Macintosh computers.

The solution, which I employ on all of my volumes, is to create a small boot partition at the start of the disk, which allows the driver and bootable partition to follow the <2GB rule. On the 9.1GB MO disks, which are 4.3GB/side formatted, I create a 280MB boot partition, and a 3998.9MB files partition. The disk driver then installs itself prior to the 280MB boot partition, and it happily boots. This also keeps my system folder separate from the files part.

You can simulate HFS+ on a pre-Mac OS 8.1 Macintosh by simply creating multiple DiskCopy 6.3.3 images that are of the desired size and minimum file allocation size. 1GB seems to be pretty convenient. Creating 4x 1GB DiskCopy images on a single 4GB volume allows you the best of both worlds: all files available on a single mounted volume from the disk, and low minimum file allocation sizes. It also allows you the flexibility of changing/creating 'volumes' of varying sizes as needed. A single 4GB volume and then multiple images inside that vary in size. My Utilities folder is over 4GB on its own, so it gets one single cartridge. Productivity, Office, they take hundreds of MB each, so they can each have their own disk volume image on the 4GB volume without affecting their minimum file allocation size.

I've found this solution to work quite well. On my LC475, I have a 37GB SCSI spinning rust drive, with a single 1.99GB boot partition, and 35GB restore images partition, setup this way. When I need things in 'one place' I can easily create a larger DiskCopy image to house the contents.
 
@Chuck(G) On my IIci running 7.1 Pro, I found that non-512b disks worked just fine when using the onboard SCSI port. Regular HFS under 2GB partition. However, my FWB JackHammer SCSI card doesn't appear to work with anything larger than 512b/sector.

I'm guessing there's some sort of limitation on the PC side, too? The larger capacity 512b/sector disks are always hard to find and/or expensive.
 
It's odd; in MO the 1024 byte/sector disks were easier to find than the 512 byte ones. In the case of the PC, however, it's mostly a matter of system software, particularly on older OS platforms such as DOS, which likes to use the same maximum sector size as the boot media.
In the Bad Old Days, (pre DOS 4/3.31), one way to get a large hard disk going was to increase the size of the sector that DOS sees (the "apparent" sector size, not the physical one). Since the 16-bit sector ordinal used by some DOS calls was a given, the only way to go past 32MB per partition was to increase the sector size. Took some patches and a special driver, but it worked as a stopgap. Compaq DOS 3.31 and PCDOS/MSDOS 4.0 fixed this by going to 32-bit sector numbers.
 
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Once I get my drives working where I fully and completely understand them, I'm going to see how large of a disc and partition combo will work on the oldest Mac and System Software version that I have. Including booting. It would be interesting to see if I can boot System 6 from a 4GB MO disk on an SE.
 
Mr Fahrenheit said:
I have a box of HP C7983A Rewritable 9.1GB Magneto Optical Cartridges, which are 4096 bytes/sector.

I purchased a batch of Lynn Medical AccuWrite 2.6Gb CCW WORM Optical Disks - P/N# 93885, which are 1024 bytes/sector. They are supposed to be compatible with the two MO drives I have: Sony RMO-S561 and HP SureStore Optical 9100mx.
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Oops! With my tiredness, bad eyes, and some stupidity, I thought the manual said CCW was compatible with the two drives I have. I was wrong!

I received the batch of CCW discs I bought and nothing I could do would make them work. Then I rechecked the manual and noticed it said only CWO discs were compatible. My purchase was a bit of a waste!

Oh well, live and learn. I purchased a set of 5x 5.2GB CWO WORM media so I can continue down this rabbit hole.

Wish me luck!

Posting this here just in case someone in the future ever searches what type of media is compatible with these two drives. I wouldn’t want someone to make the same mistake as me! Although I doubt anyone would.
 
WORM optical that aren't CD or DVD format isn't covered much because (a) it was a mess, with varying recording technologies and (b) non-interchangeability among vendors--and very small adaptation in the community. There's darned little information remaining on the web--and one might say "good riddance". Today, CD-R is considered to be obsolescent.
 
Chuck(G) said:
WORM optical that aren't CD or DVD format isn't covered much because (a) it was a mess, with varying recording technologies and (b) non-interchangeability among vendors--and very small adaptation in the community. There's darned little information remaining on the web--and one might say "good riddance". Today, CD-R is considered to be obsolescent.
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Just because something is obsolete doesn't mean we shouldn't try to research, figure it out, and perhaps enjoy it along the way.

I am interested in unique storage. So might some others.

To say good riddance solely because something is obsolete would mean we should say good riddance to the hobby in general. I mean, by that logic, why are we all even here, then?
 
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