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- UNNONDOS.DOC 01/28/90 Ward Christensen 76703,302
-
- This archive consists of UNNONDOS.EXE, UNNONDOS.C and UNNONDOS.DOC (this file).
-
- The C source is included for anyone wanting to enhance the program to handle
- diskettes - non-trivial, since for example 360K usees FD as the ID, 720K
- uses F9, etc.
-
- Possible enhancement would be determining if the drive is a 12 or 16 bit
- fat, and patching in F8 FF FF for 12 bit, and F8 FF FF FF for 16 bit.
-
- ================================================================
-
- UNNONDOS is a program designed to simply and safely patch the FAT byte 00
- of a hard disk back to an F8. Use it when CHKDSK says "probable non-DOS disk".
-
- ----------------
-
- Here's a sample output screen of UnNonDOS running.
- "<====" highlights input.
- "<----" is for comments.
-
- E:\LANG\TC>chkdsk <====
- Volume PRIAM-E created Jan 15, 1989 9:38p
- Probable non-DOS disk. <---- oops, the msg we don't want!
- Continue (Y/N)? n <====
-
- E:\LANG\TC>unnondos e: <==== <---- so fix up the drive.
-
- UN-NON-DOS (unnondos) Version 1.0, by Ward Christensen
-
- Ensures that a hard disk has an F8 in byte 0 of the first FAT.
- and that bytes 1-2 are FF.
-
- Used when CHKDSK reports Probable Non-DOS disk.
-
- Your current FAT starts out:
- 00 FF FF FF 0D 00 FF FF FF FF FF FF FF FF 08 00 FF FF FF FF
-
- After patching, your buffer looks like this:
- F8 FF FF FF 0D 00 FF FF FF FF FF FF FF FF 08 00 FF FF FF FF
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- Do you want to write the patched value back to disk? y <====
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- Writing...Done.
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- E:\LANG\TC>chkdsk e: <==== <---- lets try again
- Volume PRIAM-E created Jan 15, 1989 9:38p
-
- 22288384 bytes total disk space <---- No more problem.
- 0 bytes in 1 hidden files
- 100352 bytes in 42 directories
- 20428800 bytes in 1215 user files
- 1759232 bytes available on disk
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- 633856 bytes total memory
- 484320 bytes free
-
- Enjoy. Feedback to me on Compuserve or the Ward Board (708) 949-1132.
-