[Ham-Computers] RE: Floppy copy problem.

Wed Jul 23 20:34:00 EDT 2008

Hi Ken (et al),

As Dale mentioned, make sure there are no "logical" write-protects enabled.  This includes BIOS  settings and apps - some Anti-virus programs will have an option to prevent writing to a removable drive (aka floppy, USB, etc).

Have you tried re-formatting the disk?  Floppy disks manufactured in the past 10 years or so have been *VERY* poor quality compared to when floppies were prevalent (and cost $5 each).  Most "pre-formatted" floppies have pretty weak sector ID's by the time you buy them and it's best to re-format them before you use them.

*** BUT ***

There's a caveat - The format utility in Windows 2000/XP/Vista no longer support the "/U" switch to force an unconditional format.  In older versions of DOS, a format would *always* re-write the sector ID's and fill each sector with "F6" bytes (IIRC).  The format program in later versions of DOS (plus Win9x) would first check and see if the disk was previously formatted.  If it was, then it would verify the FAT and root directory clusters, then perform a read verify of the entire disk - THERE IS NO ACTUAL FORMATTING.  This saves time (a read-only check vs a format/write/read), but the problem with this is that the drive's error correction code (ECC) would correct weak sector bits enough that the disk verify process would pass - this would eventually lead to disk read problems (such as "sector not found" errors) as the sector ID bit patterns weakened more over time.

The "/U" parameter in later versions of FORMAT.EXE would allow you to "force" a disk format no matter what.  So even if a disk was previously formatted, the format program would treat the disk as "unformatted" and go through the full format/write/read formatting process.  Since this re-writes everyting, sector ID's are written anew - if any errors show up after the format is done, it's time to toss the disk and try a new one.

So, how do to an unconditional format using Windows 2K/XP/Vista?  Well, you force the format program to try to format the disk at a different capacity - for example, tell it format a 1.44MB disk as a 720K disk (9 sectors vs 18 sectors).  When it tries to verify the format, it will fail.  Then run the format again, but this time, specify the correct capacity (1.44M).  It will notice that disk is currently unformatted (or incorrectly formatted) and will do a full format vs a verify.  Here are the steps required:

Insert the disk into the floppy drive (assuming a 3.5" 1.44MB floppy)

>From a Command Prompt, type the following
  format a: /t:80 /n:9

Follow the prompts - it will fail after formatting track 0

Then enter:
  format a: /t:80 /n:18

This will instruct format to format a 1.44MB floppy.  It will do a quick check, notice the invalid track 0 format, and start a full format.  You'll notice that format will display "formatting" rather than "verifying" when it's doing a "full" format.

For reference, this works with all "internal" floppy drives. Some USB drives may not like the "/n:9" parameter, so try "/n:15" (1.2MB floppy format).  Even then, it may not work as USB floppy emulation isn't perfect.

Anyways, back to the original problem...make sure the disk you're using is properly formatted.  You can use the steps I just provided to do this.  Or, if you have Win95/98, you can just use the "/U" parameter.  And please, no comments on using Linux to format floppies! <g>

73,

  - Aaron, NN6O

-----Original Message-----
Sent: Wednesday, July 23, 2008 5:38 PM
Subject: [Ham-Computers] Floppy copy problem.

Hi Aaron and gang,

Hope you don't mind me calling on you again for a pesky problem with my 3 1/2" drive.

For a long time I have been unable to record on the drive. It plays back ok but when
I try to record, it reports, "Write protect error reading drive A, etc, It gives this error signal regardless of whether the protect tab is up or down!

Thinking the error was in the drive, I bought a new one and finally was able to lasso my son (who is a very busy person) and got him to install it. Well, what the heck!, the new one does the same thing! Must be a fault in the computer???

Any suggestions? Take care,

Ken   N5CM

-- 
I am using the free version of SPAMfighter for private users.
It has removed 1281 spam emails to date.
Paying users do not have this message in their emails.
Get the free SPAMfighter here: http://www.spamfighter.com/len