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Issues with USB DVD-ROM on Super Socket 7 board

ibmapc

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Not sure if this belongs here aas this computer isn't really vintage, but maybe the Mods can move this thread if they feel it is necessary.

So the machine is built up from a Gigabyte GA-5AA Motherboard (Super Socket 7) with an AMD K6-III+ 450 Processor and 128 Megs of RAM running Win98SE. When I connect a USB DVD drive in Windows, it seems to work as expected. However, if I try to access the same drive in Real Mode DOS (booting with GUI=0 in MSDOS.SYS and loading USBASPI.SYS and USBCD.SYS in config.sys and MSCDEX in autoexec.bat) the drive is correctly identified and appears to read properly until a file or directory with a long file name is found. In a DIR listing the file name is incorrectly shortened(Truncated) to 8.3 instead of being listed with the usual ~ and number at the end. So LONGNAMED.COM should be listed as LONGNA~1.COM but instead is listed as LONGNAME.COM and the same is true for directories. If I attempt to CD to a directory with a name longer than 8 Characters, DOS says that the directory is not found. In windows, the files and directories are listed perfectly and if a Command Prompt window is opened and a DIR is issued the long file names on the left are truncated but the names on the right are the correct long versions. I'm thinking this is a problem with either USBCD.SYS or MSCDEX. I've tried many different versions of these files and even a different USB DVD Drive but no better results to be had.

Has any one else seen this issue. Is there a solution? Or do I have to enter Windows to read or copy files form this drive correctly?

PS
I've also tried DOSLFN but the name are still shortened and the long versions don't show up on the right side as they should.


Thanx

Greg
 
MSCDEX only supports 8.3 file names. shsucdx (supplied with FreeDOS) claims to support long file names so it might possibly work with DOSLFN to do what you need. I have not tried it.
 
MSCDEX only supports 8.3 file names. shsucdx (supplied with FreeDOS) claims to support long file names so it might possibly work with DOSLFN to do what you need. I have not tried it.

Forgot to mention, I also tried shsucdx. No joy. But thanks for the tip.

Greg
 
The mapping of e.g. HELLOWORLD.TXT to HELLOW~1.TXT is specific to the FAT file system, while CDs and DVDs use iso9660 (plus extensions). For the iso9660, there are different compatibility levels - only the first one is limited to short filenames (level 2 allows up to 31 characters). If the DVD was mastered at level 2 or 3, then there simply are no short filenames for MSCDEX to display and use.

It is possible to master at iso9660 level 1 (giving you DOS compatibility) and provide long filenames through Joliet or Rockridge, but that is obviously not the case for your DVD. If you made it yourself, just remaster with different settings.

Have you tried the combination of DOSLFN and SHSUCDX?
 
....Have you tried the combination of DOSLFN and SHSUCDX?
Yes I have. Unfortunately, only the truncated file names are show, even though DOSLFN has a switch for CD compatibility.

That would have been my first suggestion. Running XP on the SS7 board (yes, you can do it), results in proper long-name rendering.

Actually, it works fine in Win98SE (Windows Explorer). I think XP would not perform very well on this board. I'm just trying figure out why DOSLFN won't render long file names from the USB DVD ROM in REAL MODE DOS. It does render long file names from the HDD and a USB Thuimb drive. But those are both FAT 32. I will need to find an IDE CD or DVD ROM Drive and see if it works there. I suspect there is an issue with the driver for the USB DVD ROM drive because the docs for DOSLFN indicate that it should work.
 
Again, the difference is how filenames are stored on the CD/DVD compared to a hard disk. If no short name was mastered, then there is none and the best the drivers can do is truncate. More important: Do the truncated names work when you use both?

I am quite sure that neither the drive nor the drive's drivers are at fault here, since they only provide the interface between ASPI and disk; they don't care much about the content. The problem is with the file system driver (i.e. MSDCDEX/SHSUCDX), which actually knows about files - although I am not sure how DOSLFN hooks into it. I always assumed that it hooked into the FAT driver and used the Windows-provided LFN information, which doesn't exist on your media.

Also, have you tried different media?
 
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