• Please review our updated Terms and Rules here

Software for writing to MO WORM discs?

After trying out many different types of blank (new) worm disks, along with pretty much every possible piece of software for this for Macintosh, I have come to a conclusion.

MacWarehouse catalogs never made any mention of WORM media. They had RW media but not one listing for WORM. PCWarehouse, on the other hand, advertised WORM “Mo” media.

This leads me to believe that WORM support was non-existent on the Macintosh platform. So at this point, I think it’s safe to close this up and move on, unless someone can chime in with actual experience and documented success in writing to a “Mo” WORM disk on the Mac.
 

Looks like it shipped with Retrospect Backup and treated it like a tape drive (e.g. no native file system and not mountable, only accessible through backup software.)

I found it curious that FWB Hard Disk Toolkit has a driver icon for WORM media, which seems to indicate that FWB Hard Disk Toolkit knows what WORM media is. I also found this FWB Guide to Storage which talks about WORM drives (including MO) and media:

https://cdn.preterhuman.net/texts/manuals/FWB Guide To Storage 2nd Ed.pdf

On page 194, it seems to indicate that there is a specific flag in SCSI to let the host know that it's a WORM drive specifically. Is there perhaps another jumper or toggle switch for putting it into WORM mode? It also says on page 204:

SCSI-3 SBC is an important new part of SCSI-3 that describes commands for direct access block logical unit class devices (i.e., hard drives, worm, optical, and removables). Caching is documented more thoroughly than in the SCSI-2 specification. This part of SCSI-3 includes commands to support medium changer devices such as the Read Elements Status and Move Medium commands. Optical drives have the following additional commands:
  • Medium Scan (38H) - to scan for contiguous written or blank block.
  • Read Generation (29H) - to return the maximum generation address of a block.
  • Read Updated Block (2DH) - to read a specific generation and block number.
  • Update Block (3DH) - requests that the drive replace data on the medium with new data.

So I don't know if the "Direct Access" toggle switch you found will make any difference, but it seems to indicate that it provides additional commands just for interacting with optical drives. Perhaps putting the drive into "Direct Access" mode might help. Not sure if you tried that yet.

In any event, if you can find a way to change how the drive operates, I'd recommend shutting down the computer so the SCSI bus reinitializes and is sure to look for the WORM flag upon startup.

It's also possible that MO WORM media was never intended to be used as a regular disc, and is only to be used like a faster tape drive, requiring special software to access the data.
 
As I mentioned 'way back in this thread, there is special software for PCs for dealing with this, that deals with the issue of updating/modifying content. It tends to waste a lot space when updates are performed, but the file system is like nothing you've ever seen.
Here's an early example of a ROFS: https://simson.net/clips/1991/1991.DDJ.WOFS.pdf
There are various government entities that require write-once, read-many access; the reason is that everything ever written is cast in concrete; one can only add a new version of a file, not change it. Immunity from ransomware attacks is one big advantage in these days.
Again, I have no idea of what was used with Macs, because I tend to ignore that market segment.
 
@Chuck(G) Looks like it was Dantz Retrospect Backup, at least for the Storage Dimensions drive. Could have been a special version of it that shipped with the WORM drive. Quite a few OEMs back then included special versions of commercial software that only worked with their drive.

@Mr Fahrenheit This may not be the way you want to go, but I wonder if there's a way to author the disc on a Windows PC. Assuming it's possible to write to an WORM MO in a way that it'll work like a regular disc, perhaps you can create an ISO and just use a PC to write the disc.
 
I just emailed a company that specializes in magneto optical transfers, including archives and WORM media. They replied, but I didn't realize they were in the UK. So hopefully I'll have an answer tomorrow.

Basically, I asked them if it's possible to author WORM media like a CD-R and use a WORM disc as read-only media once the write-protect tab is turned on. If so, what software to use for the HP or Sony drive. If it is possible, you could use Toast to author a .ISO disk image. Transfer that to a PC, then write it to the WORM disk.
 
@Chuck(G) Looks like it was Dantz Retrospect Backup, at least for the Storage Dimensions drive. Could have been a special version of it that shipped with the WORM drive. Quite a few OEMs back then included special versions of commercial software that only worked with their drive.

@Mr Fahrenheit This may not be the way you want to go, but I wonder if there's a way to author the disc on a Windows PC. Assuming it's possible to write to an WORM MO in a way that it'll work like a regular disc, perhaps you can create an ISO and just use a PC to write the disc.
I did try different versions of Dantz Retrospect and nothing seemed to work.

Maybe this drive is too new and the software didn’t know about it ? (Similar to how Toast wouldn’t work with drives released after it, and required updates).

I don’t really have a desire to seek out writing these on a Windows machine. Specifically because my oldest Windows computer runs Windows 10 and has no SCSI capabilities.
 
Wish I could help but the only WORM drive I have is a proprietary IBM one. The ones on my 68K macs are just normal MO.
 
Back
Top