Hello!

I downloaded the floppy image for FreeDOS 1.0, fdboot.img.  I tried to
boot it on a desktop system with AMD XP 2000+ CPU and a CD-ROM drive.
Selecting item 5 (FreeDOS Live CD only) resulted in an "Invalid Opcode".

I could also reproduce this error in bochs 2.3 configured with an
inserted floppy and an ejected CD-ROM without hard drives.  Caveat -
there should be a non-empty CD image name even if such file doesn't
exist, or FreeDOS won't find the drive.  To allow cut-and-paste, I
enabled logging to a file and the "term" frontend.

I used F8 to trace the start-up scripts, and it turns out that the crash
is triggered by the attempt to access the CD-ROM drive X: if there is no
disc in it.

Having any disc in the drive allows FreeDOS to boot (on the real
system).  Once the disc is removed, access to X: crashes FreeDOS.

This is what happens in bochs without tracing:

------------------
UMB's unavailable!

XCDROM V2.3, 7-24-2006.
Driver name is "FDCD0000".
Unit 0:  Primary-master, Generic 1234, PIO mode.

FreeCom version 0.84-pre2 XMS_Swap [Aug 28 2006 00:29:00]

SHCDX33A installed.
  Drives Assigned
Drive  Driver   Unit
  X:   FDCD0000   0

Invalid Opcode at 7217 08A4 0282 FF01 FC87 1008 000C 9C9F 0241 08CA 03BE
9530 000C
------------------

And this is with tracing:

------------------
A:\>A:\DRIVER\SHSUCDX.COM /QQ /R /D:FDCD0000 /L:X [Yes=ENTER, No=ESC] ?

SHCDX33A installed.
  Drives Assigned
Drive  Driver   Unit
  X:   FDCD0000   0
A:\>if not exist FDCD0000 goto nocd [Yes=ENTER, No=ESC] ? 
A:\>if exist x:\fdos\watcom\setvars.bat call x:\fdos\watcom\setvars.bat
[Yes=ENTER, No=ESC] ? 

Invalid Opcode at 7217 08A4 0282 FF01 FC87 1000 0000 9C9F 0241 08CA 03BE
9530 0000
------------------


-- 
Regards,
Pavel Roskin


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