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Archiving old disks that have developed bad sectors


jmccorm
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I've started to archive my old Atari floppies and I'll make them available online. I haven't found the TRACE (Tulsa Regional Atari Computer Enthusiasts) club disks online, so I'm working on the ones I have.

 

The most immediate problem I'm running into is that some of the disks have decayed over time and have sectors which are difficult to read. I have more luck using the Indus GT than a stock Atari 1050. Sometimes, I'll have bad sectors in different places. So I'm attaching THREE .ATR images which seem to have most of their bad sectors towards the end of the disk, and mostly in different places.

 

Is there any good way to merge the three .ATR images into an image with the best reads?

 

Also, can anyone recommend a sector copier that automatically detects single/enhanced/double and will go for LOTS of retries?

 

Thanks

jmccorm

 

THREE COPIES OF A DISK, SECTOR ERRORS MOSTLY IN DIFFERENT LOCATIONS:

TRACE Club #32 Utilities October 1985 BasicBadSectorsAlt1.ATR

TRACE Club #32 Utilities October 1985 BasicBadSectorsAlt2.ATR

TRACE Club #32 Utilities October 1985 BasicBadSectorsAlt3.ATR

 

ONE CLEAN CLUB DISK THAT WORKS JUST FINE:

TRACE Club #29 July 1985 Basic.ATR

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Impeccably clean drive head will help, if you spin the disks gently by hand you will normally see some crud at the error point, a gently rub of the spot with a cotton q tip (full head no stick edge to damage anything) usually will get the job done... if it doesn't ship them off to someone with a Kryoflux or whatever the other one is and they be able to recover it.

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Is there any good way to merge the three .ATR images into an image with the best reads?

 

 

 

I can write a general tool for this, but in this case there were only a couple sectors involved so I did it with some general binary cut/patch tools I wrote years ago for this kind of work.

 

The disks here are identical except for 5 sectors:

010310 SECTOR 519 #1 GOOD, #2 BAD, #3 BAD

010690 SECTOR 526 #1 BAD, #2 GOOD, #3 GOOD

010790 SECTOR 528 #1 BAD, #2 GOOD, #3 GOOD

010d10 SECTOR 539 #1 GOOD, #2 GOOD, #3 BAD

012c90 SECTOR 602 #1 GOOD, #2 BAD, #3 BAD

 

So I took disk #1 and copied two sectors from disk #2 onto it to patch it up.

 

Sector 550 and 617 are still broken, so this isn't a complete restoration of this disk. These are in the files CONVERT and EPSET, if we find another source for these we can likely complete the disk repair.

merge.ATR

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I can write a general tool for this, but in this case there were only a couple sectors involved so I did it with some general binary cut/patch tools I wrote years ago for this kind of work.

Sector 550 and 617 are still broken, so this isn't a complete restoration of this disk. These are in the files CONVERT and EPSET, if we find another source for these we can likely complete the disk repair.

 

Nice work, thank you very much for your time and effort!

 

Let me try a bit of drive cleaning and see if I have a bit more success with my archiving. I'd hate to have someone go through the effort of creating a tool just to handle a fix for one person's problems.

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Impeccably clean drive head will help, if you spin the disks gently by hand you will normally see some crud at the error point, a gently rub of the spot with a cotton q tip (full head no stick edge to damage anything) usually will get the job done... if it doesn't ship them off to someone with a Kryoflux or whatever the other one is and they be able to recover it.

 

Thanks for the tip. I'm probably going take the advice on the drive head, but hold off treating the disk(s) that don't read cleanly. There are probably less than a dozen surviving copies of each of these disks, and I'd prefer to send them to someone with the experience and better equipment (like you mention) rather than risk my own inexperience on damaging them even further.

 

I don't think the software on these disks are incredibly 'wow', but the whole Club Disk experience is something that I haven't seen much of online, so they're kind of neat to look through.

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Nice work, thank you very much for your time and effort!

 

Let me try a bit of drive cleaning and see if I have a bit more success with my archiving. I'd hate to have someone go through the effort of creating a tool just to handle a fix for one person's problems.

 

I find fixing disks like doing Sudoku, quite enjoyable in small doses. This one proved to be a nice morning puzzle.

 

I took a quick look at the two damaged files on the disk. CONVERT is from ANTIC, which I found on a November 1988 ANTIC disk. So I copied over the appropriate bytes and fixed the sector link data (the last 3 bytes), then compared the LISTed results. This showed two nearly identical files (a good sign), but with 4 variables (2 distinct) different in the restored area, meaning the variable tokens weren't the same. I determined that token 0x81 in the ANTIC file was 0x8c on this disk, and token 0x8f was now 0x9a. So after patching four bytes the listings matched up, so I've recovered sector 550 with high confidence.

 

As for EPSET and sector 617, the damage is at the beginning where there are a series of REM lines. I patched in the missing lines as just spaces to get a functional program. The credits then read ANALOG MAGAZINE ... This version by Geary Fowler - Tulsa OK. This pointed me back to ANALOG issue #11, EPSET by Dick Tedeschi. The REM lines from that program are done a little differently, but I was able to use the ANALOG original to restore the lines that should be pretty close (if not exact).

 

So here's the disk fully fixed.

merge2.ATR

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I find fixing disks like doing Sudoku, quite enjoyable in small doses. This one proved to be a nice morning puzzle.

[ ... ]

So here's the disk fully fixed.

 

THAT is some dedication. Thank you, sir!

 

Adding your recovery story to the TRACE collection. Also, as the remaining active TRACE member, I am naming Atari_Ace at the club's Honorary Digital Forensics Officer. Nice work!

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Hmmm,

 

a sector-copy program with "endless" retries for reading bad sectors ?!? Think there are several programs for the A8, one I use quite often is Diskcopy from Turbo-DOS XL/XE. Attached it as a sort-of bootdisk (a file with a bootloader) here. It requires a min. of 64k RAM. Usage:

 

- press 1x ESC to reach the setup

- use arrows up/down (without control) to move up/down

- press Return to change an option

 

- set "Continue on Error" to on if you want the program to ignore all errors and simply continue reading (it will write blank sectors for any bad sectors); set it to off if you want to read all the data on the disk, it will respond with an Error for a bad sector giving you the options to Continue, Abort or Retry (press C, A or R respectively). So when you have a bad sector, you can press R / Retry 10, 100, 1000 times or as often as you wish until either the drive, the disk or your finger breaks...

 

- press 1x ESC again to leave the setup

- press Return (when not in setup) to start the copy process

(you can press the Start key to pause copying and go back to the setup; but when reading the Directory, some memory is used and all data copied so far is lost - you then have to start over again)

- when done, hold down Select and press Reset to leave the program (do a coldstart)

 

Diskcopy can read/format/write 90k/130k/180k/360k, it supports multiple drives, Turbo, Happy, Speedy and XF floppy speeders and up to 320k RAM. Alas, only when loaded from Turbo-DOS XL/XE, it uses up to 320k RAM, otherwise only 128k RAM (and if you are using two drives it does not use XRAM at all, just the standard 64k RAM)...

 

P.S.: I have not tested Diskcopy with any other floppy speeders, than the four mentioned above; it may or may not work with US-Doubler, Indus and various other floppy drives and speeders. The option "Quit on empty sector" is for DOS 2.x diskettes only (DOS 2.0, DOS 2.5, Turbo-DOS, Bibo-DOS and compatibles), set it to off when copying non-DOS 2.x disks (e.g. MyDOS, SpartaDOS, bootdisks, etc.)...

Diskcopy.zip

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Hmmm,

 

a sector-copy program with "endless" retries for reading bad sectors ?!? Think there are several programs for the A8, one I use quite often is Diskcopy from Turbo-DOS XL/XE. Attached it as a sort-of bootdisk (a file with a bootloader) here. It requires a min. of 64k RAM.

 

Thanks, I'll give it a try. In the meantime, I've been using an indirect solution, MyCopyR!... which I got from you! (Option "F".)

 

MyCopyR! also has that feature to continue a copy if it encounters an error. I don't know how it compares to this program, but where it was more useful than other copy programs is that when it comes time to write to the destination desk, it will *skip* any sector that was unreadable.

 

So I can try to copy a disk using the Atari 1050 and get some unreadable sectors. Then I can try again on the Indus GT and get a different set of unreadable sectors. But if I used the same destination disk (on two or more attempts), then only the good sectors are copied through. Some of the other copy programs will write them out as blank sectors, so that makes MyCopyR! really useful when you're making multiple attempts (and even with totally different drives) to recover some difficult media.

 

Thanks for all the help with copiers!

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yep that how I normally go about it, clean it all, read the disk ingnoring but noting errors. sometime I read the sectors going backwards to the error after recleaning...

You get all the easy good stuff without risking damaging anything more than is already damaged that way. then the retries, cleaning etc. begins. It's usually easily put back together.. if it looks or sound like a no go.. or even looks to worsen in the slightest... off to a proper recovery tool it goes.

You can make atx and vapi etc images, some of the peeps here can look at those and fix stuff for you just from those. If you do use a streaming disk recording method, sharing that data with the recovery teams here usually yields very favorable results... sometimes you make a couple of these raw format files and send them, next thing you know it's all been compared.. tried and working!

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You can make atx and vapi etc images, some of the peeps here can look at those and fix stuff for you just from those. If you do use a streaming disk recording method, sharing that data with the recovery teams here usually yields very favorable results... sometimes you make a couple of these raw format files and send them, next thing you know it's all been compared.. tried and working!

I never had a Happy drive so I don't have much experience with disk tools that can handle errors. Are these tools going to be any good on a stock 1050 or Indus GT, and if so, what are they?

 

Thanks,

jmccorm

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