Floppy disks that stop being writeable?

بواسطة wyrdwad

Paladin (934)

16-07-2016, 07:58

Hey all,

I've been having some unique issues with my floppies recently, and figure some of you guys may have an idea what the cause could be.

I have a series of blank floppy disks that I've labeled A through D, which I use as generic disks whenever I want to write some new game and try it out. These have been prepared as you'd expect: I put a piece of tape over the holes of 1.44 MB floppies to trick the MSX (and my Windows USB floppy drive) into thinking they're 720kb disks, and formatted them through Disk Manager (on a Windows 7 machine) prior to writing MSX data to them for the first time.

For the last year or so, I've had no trouble with this, and have used this technique to sample any number of games on my Panasonic FS-A1WX MSX2+ system.

However, recently, all four of these disks have just immediately started giving me "The operation was completed successfully" within one second of starting a write through Disk Manager -- I'm unable to write any data to them at all anymore, as they just immediately shut down on me as soon as I try. Even when I try to reformat them in Disk Manager, I just get "The operation was completed successfully" the second I start. And when I try to format them on my MSX itself through CALL FORMAT, I get a bad disk error.

I've tried writing to other disks in my collection (ones that I had previously "permanently" written to, with no intent of ever changing their contents), and some of those have started giving me the same error -- though others work just fine, and I'm able to write to them without any trouble at all.

I would just assume all these disks went bad and leave it at that, but what's really weird here is that every single one of these "defective" disks will still boot in my MSX with the last game I wrote to them -- no signs of trouble reading any of the data on them whatsoever, I just (seemingly) can't ever write over it again. It's as if the disks have copy-protected themselves without my knowledge or consent (and no, I haven't touched the copy-protect tab on any of them).

Is this... normal? Or is something funky going on with my disks?

Any help you can provide here would be appreciated, and if my disks HAVE gone bad, any ideas as to why that might've happened would also be appreciated -- I take very good care of my disks, storing them in a plastic disk case, in a plastic drawer, away from direct sunlight and otherwise out of harm's way.

Thanks!

-Tom

بواسطة meits

Scribe (6530)

16-07-2016, 15:05

it's a weird case indeed.
can you format them on your pc as a HD disk without the tape covering the hole? If that succeeds you should have a new blank disk which you should be able to use as a DD disk again after covering the hole again.

Can you still copy anything on it with your MSX using a sector copier?

بواسطة wyrdwad

Paladin (934)

17-07-2016, 20:31

Hadn't thought to try removing the tape and formatting them as regular 1.44 MB HD floppies. Just tried, though, and no luck: Disk Manager still exited immediately (the actual message, as written, is "A: The operation completed successfully."), and when I tried to open a DOS window and format the disk via "format a: /u/q" I was greeted with "Invalid media or Track 0 bad - disk unusable."

I decided to run a few tests on one of the other disks that was giving me a problem, which I'd previously written disk 1 of the T&E Soft game "Rune Worth" to. I loaded up MSX-DOS, swapped the Rune Worth disk 1 into my drive, and typed "dir," which yielded a "File not found" error -- no surprise there, as Rune Worth isn't an MSX-DOS game, but a binary title.

I didn't care about potentially losing it, though, so I loaded up BASIC and wrote a simple "hello world" program, which I then saved to the disk via save"hello.bas".

I reset my MSX, and despite numerous aborted attempts to format this disk, as well as saving a .bas file to an otherwise binary program disk, Rune Worth's intro began playing without any issue.

So I stuck in the MSX-DOS disk again, reset my system, swapped in the Rune Worth disk 1 again, and typed "dir" again -- and this time, it was showing HELLO.BAS. Which means the disk is 100% writeable on the MSX itself, but un-reformattable on either the MSX or my Windows PC, and un-writeable on my Windows PC.

Looks like that disk will be Rune Worth disk 1 forever, now! With a bonus "hello world" program on it for good measure.

Really not sure what the problem is. Nor why it just popped up recently -- the only difference I can think of is that I have a new Windows PC as of about a month ago, though I'm using the exact same USB floppy drive I've been using, and the exact same copy of Disk Manager, on an identically-versioned install of Windows 7. And I've been able to successfully write numerous disks on this PC so far (including all four disks of Rune Worth, before all four disks because un-rewriteable).

It really is all rather odd!

Thank you for your help, though. I greatly appreciate it.

-Tom

بواسطة Manuel

Ascended (19201)

17-07-2016, 21:58

Has it occurred to you that the disk may just have gone bad? Or do you get it with all of your disks now?

بواسطة wyrdwad

Paladin (934)

17-07-2016, 22:29

If the disk has gone bad, though, then why is the MSX still able to read it and write to it?

-Tom

بواسطة Manuel

Ascended (19201)

17-07-2016, 22:31

It wasn't able to format it, I thought you said?

By the way, I'd always format disks for MSX usage in the MSX and never on a PC. The MSX format is also optimized for itself and will improve performance.

بواسطة wyrdwad

Paladin (934)

17-07-2016, 23:01

I'm not able to reformat it anymore, no -- from either the MSX or my Windows PC. And I'm not able to write anything to it from my Windows PC anymore, either. But I'm still able to play the game that's already on it, and I'm still able to save .bas files or game save data onto it via the MSX. So it's, like... a selectively bad disk.

And it's one of many -- I'd say a good half-dozen or so disks in my collection currently suffer from this problem.

-Tom

بواسطة Manuel

Ascended (19201)

17-07-2016, 23:23

If a disk won't format on my MSX anymore (and the disk drive of the MSX is known good), I'd throw away the disk as it's clearly unreliable.
You probably destroyed the game by the way, by saving a program on it... unless you're really lucky

Did you try other programs on your PC to write to it?

بواسطة wyrdwad

Paladin (934)

17-07-2016, 23:37

I don't know of any others, honestly. I used an MS-DOS prompt to try formatting the disk when Disk Manager failed, but those are the only things I've tried. If you have any recommendations of alternate disk-writing programs for MSX that I could try, I'm definitely all ears!

And you would think I destroyed the game by saving that program on the disk, but I progressed quite a ways into it without any issue, so it seems like saving that .bas file onto the disk didn't actually faze the program one bit! It's very odd, as I totally expected it to be "bricked" after that, and was pretty shocked that it wasn't.

-Tom

بواسطة Vampier

Prophet (2405)

18-07-2016, 05:54

you could try to format is in single density (360Kb) if you're lucky the flaw is on the un-used part of the disk.

بواسطة wyrdwad

Paladin (934)

18-07-2016, 06:18

I did try that with one of them, but to no avail.

A tech-minded friend of mine believes the problem may lie in my USB floppy drive. As she put it:

"I think either the disk's FAT sectors are physically damaged, OR the floppy drive is having trouble writing the FATs. The FAT is the very first section of the disk, so if your drive is wearing out, the magnetic head may not be moving to the very beginning of the disk correctly."

She seems to think that the reason I'm still able to play games off of these disks, despite being unable to format them or copy new data to them from Windows, is because of the way the MSX reads binary data:

"Windows and MS-DOS uses the FAT to read whether or not a disk is bootable and boots from that.
MSX-DOS is a little different. Because MSX has cartridges, there's a built-in BIOS that has its own booting system to load cartridge games from the ROMs. When they made MSX-DOS, they added in the ability to use that same system to boot a ROM on floppy without the use of the standard FAT. So a binary ROM written to a floppy the way a cartridge would be, that's probably gonna still boot just like normal, even if the FAT area of the disk is corrupted. And if you try to format and it fails, the rest of the data will stay right there and still work most likely."

I might try replacing the drive (since these drives are pretty cheap) and see if I have more luck, both with these disks and with new disks.

-Tom