Fun data recovery... from 1984

Posted by: FireFox31

Fun data recovery... from 1984 - 27/08/2008 02:31

Does anyone know how to take a hard drive image over a serial cable???

My friend needs help recovering a corrupt document from his word processing computer - an IBM XT clone from 1984. The machine has an RLL ~40 meg hard drive; incompatible with modern IDE, and with an odd ISA controller card. I extracted the drive's data using my trusty empeg serial cable and Lap Link 3 for DOS.

The corrupt document has 0xff was written to the first 3/4ths of the 1 meg file. So, I'd like to take a sector-by-sector image of the drive and search it for a deleted-but-intact version of the file. But serial cable is the only way I can see to get data off.

Is there any software for drive imaging over serial, which would run on an 8088 with 640k ram running DOS 3.3 (or higher, via boot disk?). Or is there a better way to search for a deleted file? Thankfully, WordPerfect files are nearly plain-text, so it should be easy to spot.

Thanks for any input. Until then, back to my hex editor to restore the partial file that I have.
Posted by: pca

Re: Fun data recovery... from 1984 - 27/08/2008 06:45

Would it not be easier to track down a modern-ish motherboard with an ISA slot, and plug that entire drive system into it? Then a recent OS, either linux or XP, for instance, would make the searching much more straightforward.

I've got, for instance, several QDI Kinetiz A motherboards that I hung onto for exactly this sort of thing, which have 1.4GHz Athlons in, and have ISA, PCI, and AGP slots. I am sure that a version of linux still exists with drivers for that card, and reasonably sure that XP would still support it.

One thing to bear in mind is that drives of that era usually don't auto-park the heads, you have to remember to do it manually via a dos command. If you don't, moving the drive can corrupt it badly.

pca
Posted by: mlord

Re: Fun data recovery... from 1984 - 27/08/2008 11:08

Quote:
The machine has an RLL ~40 meg hard drive; incompatible with modern IDE, and with an odd ISA controller card.

Sounds like a PerStor card. I used to have one of those here (a great way to get more capacity out of the tiny drive sizes back then).

I have here a CS5530 eval board: basically a custom micro-ATX motherboard, with PCI & ISA slots, and lots of other goodies. It boots/runs Win98, Linux, and probably most other OSs. Integrated video, USB, serial, etc.. There's a CPU and a stick of PC100 SDRAM on it.

If you think it will help, then it's yours for the cost of postage.

Cheers
Posted by: FireFox31

Re: Fun data recovery... from 1984 - 27/08/2008 16:13

My first attempt was to connect the ISA card to a newer system. I dropped it into an AMD K6-2 machine, but it wouldn't get past POST. I have three other ISA machines to try.

The controller is a Western Digital 1002a-27x, attached to a Seagate RLL drive. I found very minimal data about the card online, in hopes of configuring it to work in the newer motherboards. My fear is that the controller (from an XT) is incompatible with AT/ATX ISA slots and I'll somehow damage it or the hard drive by fiddling with it. But I've got the data now, so I'm less worried.

ISA (and PCI) controller cards have always worked for me. But with this, it seems that I have to convince the BIOS to accept it. The XT has no CMOS, so I think the system resources for the controller are hardcoded somewhere. I think that's the problem; this XT board isn't used to AT's flexibility.

I'll look online for more info re: XT controllers in newer motherboards. I'll also try DOS 6.22 undelete (via 360k 5 1/4" floppy boot disk). I'll even try Ghost sector-by-sector image over parallel data transfer cable... if I can fit an old version of Ghost on a 360k floppy. I doubt the machine will recognize a high density floppy drive.

But even with a drive image, hunting through fragmented data with a hex editor will be terribly hard. Wish I could search only the "blank" space for file fragments. It's only 40 meg, so finding "-1WPC" (the file header) can't be too hard.
Posted by: gbeer

Re: Fun data recovery... from 1984 - 29/08/2008 00:28

zip 2.2 file xfer over serial

There are a couple more on this site.
Search for "serial file transfer"

edit: fixed link. OOps Misread the original post you already have Lap Link.

Edit: did find this under 360k uneraser
Says it runs under dos3.1 to XP
Posted by: FireFox31

Re: Fun data recovery... from 1984 - 29/08/2008 01:40

Awesome, thanks for the uneraser. Runs on Dos 3.1? No problem, I've got Dos 3.THREE!
Posted by: FireFox31

Re: Fun data recovery... from 1984 - 05/09/2008 03:04

I got the RLL HDD controller and drive to boot in my Pentium 166, but I had to disable all of its onboard IDE, and the floppy drive didn't work correctly (because it was controlled by the RLL controller?). This shows that it is possible.

Now, in order to run Windows-based recovery tools, I need to run both the RLL controller and another drive with an operating system at the same time. RLL + onboard IDE? RLL + bootable CD OS???


I also got the XT to boot to a DOS 6.22 5 1/2" 360k floppy disk that I made. I ran UNDELETE and found one recoverable file - a temp file containing the document at the time of the corruption. I recovered it, got it on a real machine, and examined it in hex to find it was also corrupt like the other document I recovered... but it seems to be an older version of the document.


It's back to running Windows recovery tools on the RLL drive if I can get it to boot with a Windows OS somehow...
Posted by: wfaulk

Re: Fun data recovery... from 1984 - 05/09/2008 03:14

Again, make an image of the drive. You didn't say what you got your P166 to boot into. Windows should be able to mount images with WinImage.
Posted by: FireFox31

Re: Fun data recovery... from 1984 - 05/09/2008 09:41

Ah, I got the P166 to boot to DOS 3.3 on the RLL drive. The machine saw the drive as the primary master once I disabled its onboard IDE controllers. But with the controllers enabled, it would not boot at all. No matter how I look at it, the RLL drive must run without any other drives attached.

I'm actually giving up on this because the recovery effort would never work. On the 37 meg drive, there's only 1.5 meg of free space. The chance that a deleted old version of the 1 meg document is on that 1.5 meg is essentially impossible. No sense in me conjuring a Pentium to boot to Windows with an RLL drive ISA controller attached, only to find that the free space contains Word Perfect temporary files. The fragmentation alone makes this impossible.

Maybe the file got corrupt because the machine ran out of hard drive space while working on it. Still, it's pretty harsh to turn 760k of a 1meg file into 0xFFFFFFFFFFFFFFFFFFFFFFFFFFFFFF.

Thanks for your input. This machine is going back to its owner.
Posted by: Roger

Re: Fun data recovery... from 1984 - 05/09/2008 12:01

Originally Posted By: FireFox31
This machine is going back to its owner.


Don't bother. Bin it. Get a new one.
Posted by: larry818

Re: Fun data recovery... from 1984 - 05/09/2008 14:26

Originally Posted By: FireFox31
Maybe the file got corrupt because the machine ran out of hard drive space while working on it. Still, it's pretty harsh to turn 760k of a 1meg file into 0xFFFFFFFFFFFFFFFFFFFFFFFFFFFFFF.


It's more likely that it got trashed by trying to create a 1 meg file on a machine with something less than 640K of memory. Lots of programs back then would do this.