How to make a NEC 4x4 CDROM work with OS/2

By Tony Ironside
 * Date: 1996/02/16
 * File: nec4x4.zip

I stumbled upon (quite by accident mind you) that some of the updates to the CD file system in fix pack 17, corrected some problems I had with an NEC 4x4 CD changer. In particular, under OS/2, only one drive letter would be assigned to the CD drive, leaving the other 3 bays unused, as of fix pack 17 this is corrected and 4 drive letters are associated with the CD drive.

Why I packaged this set of files instead of telling you to download fix pack 17? :)

When I installed fix pack 17, it well did not work at all on my system, the machine would reboot and come to the desktop, and just hang there, leaving me no options but to cold reboot, I noticed that on reboot, I had an extra three drive letters somewhere, one program I use (super virtual disk) creates a virtual floppy disk for use with programs, and it assigned the drive letter of K: instead of the usual H: so I realized that the os2 CD-ROM file system must have been updated to include multi disc changer (yahoo!) I packaged these, cause 1) it's much smaller than fix pack 17 and 2) fix pack 17 killed my system and I had to reinstall OS/2.

Files included in this patch 12-04-95  9:34p     41795           0  CDFS.IFS 5-19-95  5:16p      3949           0  CDROM.TBL 10-30-95  3:13p     30636           0  IBM1S506.ADD 10-30-95  3:14p     20358           0  IBMIDECD.FLT 10-30-95  3:05p     26580           0  OS2CDROM.DMD 12-04-95  9:24p     13264           0  UCDFS.DLL read.me (this file)

Conventions used for following instructions:

c: refers to your os/2 boot drive


 * How to install


 * Copy cdfs.ifs to c:\os2\boot


 * Copy cdrom.tbl to c:\os2\install (not needed but it updates selective install to list 2 other cdroms I think :)

Copy ibm1s506.add and ibmidecd.flt c:\os2\boot these files may not be needed, I don't use them on my system, but some systems may require them, just in case :)


 * Copy os2cdrom.dmd c:\os2\boot (this is the file that makes all the diff with-ought it, it will not function in the correct manner)


 * Copy ucdfs.dll c:\os2\dll

Now reboot your machine, it may take longer to boot, because OS/2 decides it wants to check all of the drives in the system on bootup, changing the CD's, and stuff takes some time, quickest way around this is to pop a cd during bootup, or have no CD's in the CD drive, but it will boot, it just takes a minute extra or so.

Repercussions: you now have 4 CD drive letters on your system under multimedia (at least here) it gives you 2 cdaudio devices, so you can have a CD in 2 possible drives, which 2 you select you have to choose in multimedia setup note that you CANNOT play a CD from any of the 4 drive, OS/2 doesn't track that.

All in all it works well, when changing the drive letter from the command line, you may have to do it twice, it doesn't change the CD fast enough for OS/2, so it will give an error message, but if you change the drive, get error message change again, it will be ready for you. From the WPS it works fine, the WPS is apparently patient enough for the drive to change :)