**Need Setup HELP** with Classic Amiga 2000 HARD DISK (Bridgeboard)

[wbrejnia]

The expert on Bridgeboards: BlindGerMan: http://www.a1k.org/forum/showthread.php?t=33435

Thank you Leofoe.  This is very good information on Bridgeboard.
EXCELLENT INFORMATION. and a Good Contact if I need more.

All German, but Google Can translate, and so can my wife.

[wbrejnia]

HARD DRIVE (DATA RECOVERY) on (MDOS Partition) * OPTION *

Pat,

I've been thinking, and I believe this was one of your suggestions on next steps...

Sure it would be nice to fix those two Partitions (MS DOS) and (AMIGA DOS).

Even better to be able to Boot off either.

I'll learn more when the ISA-IDE adapter arrives (if that works).

However I'm thinking that I might want to start looking into some kind of DOS DATA recovery tool (Could be in Norton 6.0).

Since I can talk to the WD controller and it can read the RAW MFM disk, could I READ-Scan the drive byte-by-byte.  Possibly just see a list of Files that are there.

I'm going to read up on DOS file structure (boot sectors, etc), but Norton Tools and other-Tools should have more know how then I'll ever figure out my lifetime.

Maybe there is a tool where I can manually put in the Partition info, knowing the tracks and sectors, etc (without updating the Partition Info on the Drive)

If that's possible, then next step would be to transfer those bits/bytes on a 2nd Media (somehow is another question), and possibly reconstruct some files on the (486 Machine, or even my Personal Windows Machine).

I would focus on the FIRST DOS Partition, since that is what DOS tools understand.

I could be lucky and even be able to View my School work paper which I know for certain was written in ASCII test. (Hopefully on the DOS side.  I bet I used a DOS word-processor or text-editior,  not a Amiga one).  I know that paper didn't include any Fancy images (like today's MS Word abilities), since I glued in Paper Photos to complete the Project.

1) The main thought in my head is NOT to WRITE  "a Single BIT" to that hard drive.

2) Instead, READ every "bit/byte" that I can, before trying any Partition Fixes.

[wbrejnia]

DOS Based HARD DRIVE TOOLS

There is a ton of stuff out there for DOS Disk Tools.

This link has some interesting stuff.
http://www.bttr-software.de/freesoft/disk1.htm#repair

Must be careful since non-commercial stuff could be dangerous.

Best to see what Norton can do.

My limitation at this point is I only have limited space on the B: 5.25" Floppy (360K) and not all available.

Maybe that ISA/IDE adapter will allow me to have both the MFM-DRIVE (Conncted to WD-ST Contrller Card) and the IDE Drive(on ISA/IDE Card) on the Amiga PC at the same time.

 (That didn't work in the 486 due to Controller Card Conflict, but I may be able to get the 486 dual connected with the ISA/IDE adapter)
(But I would still need a Floppy Controller to boot on the 486)  
Would need to buy one of these $$$ CRAZY EH?? (Not tested!!) $$$ http://www.ebay.ca/itm/MicroSolutions-CompatiCard-I-PC-XT-8-bit-ISA-Floppy-Controller-VINTAGE-1987-/232222790211?hash=item36118e9243:g:xxcAAOSwbsBXjBbs

[[ I should just FORMAT THE MFM Drive, Proove it's good, and Sell the 8-BIT Western Digital Controller Card with the MFM Drive, and BUY A WHOLE NEW FISH TANK )  Hilarious.

At least the Amiga PC has a Floppy Drive.

[wbrejnia]

Some possible options for the Hard Drive Data Dump (Needed for the Recovery Tool Program).

Yup, might have to build my own Data Recovery Lab.    

Really hoping OPTION 1 works.

[wbrejnia]

I wonder if DOS version of Ranish Partition Manager could be of some help, as it reads many kinds of Hard Disks values.

Raffaele,

I downloaded, read up and tried the Ranish program.  Nice Lite program.

Help file is Super to describe DOS File system in detail (Everything I needed)

Nice feature to copy MBR when (picked up).

But this boot of the Amiga PC,  didn't pick up Partitions.

(So if Amiga ever boots up with Partition, I'll make a copy of the MBR.

[wbrejnia]

The problem with using DOS recovery tools - they are not going to recover data stored on the Amiga partition.

You would be gambling on the data you see being purely in the DOS partition.

Anyway, all looks good from here. I really don't see why you are reaching fos DOS recovery program.

We'll I actually don't know what I'm doing, but am trying to learn all the bits aand pieces.

The reason for DOS anything, is the First Partition of the MFM disk is a DOS PARTITION.  

Maybe Adisk is not going forward till it has a first Partition clean (since the Menu for Adisk is for both DOS and AMIGA).

Decades ago I must have created the DOS partition, and the Amiga Partition (formatted and installed stuff)

I will try and fix the First Partition if possible (FIRST)

I am wondering if I can actually do one of these things:

- (A)  READ the Raw Data and see if I can get a feeling of what's on that disk.
- (B) Copy the disk somehow and rebuild on another good disk

- (C) Longshot, but Use a disk editor and reconstruct the MFM disk by writing back some information that has been lost (like the Boot Sector etc).  (REFRESH the information from things I know. DRIVE SPEC and possible Format structure)

This (C) Idea comes from reading that help section of Ranish's PC Manager as quoted below:

The version of DOS at the time, matches the technology and DISK systems that my Amiga PC was built with.

---------------------------------------------------------------------------

Classical MS-DOS file systems

0x01, "DOS FAT-12"    
0x04, "DOS FAT-16 (under 32M)"    
0x06, "BIGDOS FAT-16 (over 32M)"    

All file systems have the same structure:              
[Boot Sector]        
[First copy of FAT]        
[Second copy of FAT]        
[Root Directory]        
[Cluster 2]        
[Cluster 3]        
[Cluster 4]        
...        
Boot sector, FATs, Root Directory, and clusters have fixed sizes,    which you  can set only when you are formatting the disk.      
   Space for all subdirectories and files is allocated by clusters.    
If cluster size is 8 sectors = 4,096 bytes, when you create file with    size of 1 byte it will get entire 4,096 bytes cluster.      
There is an entry in FAT (File Allocation Table) for each cluster,    which tells if cluster is free, allocated, or damaged. Therefore size    of the FAT determines maximum number of clusters.

FAT-12 file system is limited to 4084 clusters. It is used on the    floppy disks, but you can also use it on a small hard disk partition.            

FAT-16 was used on early hard disks. Original version could have    up to 65,000 clusters on partitions up to 32M.          

BIGDOS FAT-16 which was released with DOS 3.31 doesn't have 32M     limitation and can be as large as 2G. For backward compartibility    all DOS versions later than 3.31 will accept both FAT-12 and FAT-16    file systems in the BIGDOS partition.  

-------------------------------------------------------------------------------------------

There is a MANUAL DISK Editor in DISK DOCTOR.

And Maybe those things DISK DOCTOR was trying to do is equivalent to a refresh of MBR etc.  

Disk Doctor asked two questions (If disk was readable before, and if disk was bootable before):

- Then first recommendation was (It would fix signature In Partition Table)
- Next was to (Fix Master Partition Program) so Partition Could boot.

-> Isn't that was ADISK was also trying to do (With out a "Do you want to continue Y/N").
   Why would someone write a program to proceed with destruction, and no prompt (just hit any KEY)
  I COULD NOT GET OUT OF ADISK at that point without POWER OFF.

-----> I think the AMIGA PC booted from the C: drive (Partition 1 of MFM Drive)  
-----> ** AFTER JANUS Loaded off Workbench Floppy ** (That happens now, but off the 5.25" Floppy boot disk)
-----> If I fix HD Dos Partition 1, make it bootable, (if not corrupted data) then it might boot with WorkBench From Cold start.

** HOW TO FIX THE AMIGA PARTITION is a totally separate thing , but what if things continue once First Partition is good **

Can't hurt to try (AFTER DOING A RAW SCAN and read contents).

Again, I know nothing much.  Hoping for some luck on something complex, but yet primitive.

Will search on the Web for Manual Disk Editor Restoration.

Setting up the Explorer PC (with an Empty IDE Drive) to fool around with FDISK, The tools I have.  (ie Format a disk, put on some files, DESTROY, Corrupt MBR).  Learn the tools for 1 DOS partition.

I have nothing to loose since I have nothing now.
Any tidbit I get is BONUS.

-Then I low Level Format the Drive.
-Partition it Fresh.
-Format, and start like New.-Scan it for errors, and put the (Controller and Disk, if good) up for Sale on Ebay.


POP in the ISA-IDE Adpater with a IDE Drive, and I'm done!!

[wbrejnia]

JUST TRIED SOMETHING CRAZY and it's working!!

I have 3 keyboards:

- One for Amiga which serves for (AMIGA and AMIGA-PC)
- One for 486 PC
- One for Amiga-Explorer (Windows XP)

Well when typing on the Amiga-PC, using the AMIGA KEYBOARD, I've always went into AMIGA MINDSET.

After writing post above, I was thinking I can't wait for the ISA-IDE adapter to arrive so I can try some things on the AMIGA-PC.

Then it hit me "ADISK" is an Amiga Utility, but IT IS for AMIGA-PC (So DOS).

- I Formatted a Fresh DOS 6.2 (3.5" FLoopy) Bootable
- Copied over all the DOS Bridbgeboard disk files
- Created a CONFIG.SYS with (DEVICE=JDISK.sys)
- Boot the Floppy in my WindowsXP PC

ADISK WORKS!! (Picked up the DOS Partition on HD)... Full menu including option to make an DOS & AMIGA PARTITION (like like the MFM Drive on the Amiga-PC).

I'm going to replace the IDE drive in the XP machine (with a spare) and start playing with all the tools I got.  (RISK FREE)

NO more (downloading on my Workstation....copying to USB, moving to 486, then copy to 5.25 (low capacity), then to Amiga PC).

[wbrejnia]

This is the bottom line. You can't do anything on an XT system unless you are prepared to make bootdisks with config.sys set just right.

Once you are prepared to do that, everything becomes accessible. Until you do that, expansions are a closed off area... and that is DOS and the XT for you.

Told you enough times, data is probably OK. Now get lots of practice, it is very good idea to have experiment setup to learn from. :laugh1:

Hard drive heads MUST be OK, if not they would have destroyed disk info areas already. It's a go, green light, everything OK indicator, on that hard drive.

Pat, Sorry if I confused you.  Should have done a diagram.  Or been more clear. (There are 3 computers)

What I just did above was not on the 486AT machine (Window3.11) with the ISA slots (and no On board HD Controller).  (That would have been great since I could play with the ISA-WD-MFM controller and talk to the MFM drive)
I CAN'T USE THAT HOST since the HD Controller is multi purpose (HD-FLOPPY), so I can't get a floppy boot when I plug in the WD-MFM-Controller card.  Plus PC freezes after BIOS when I do.

I used the WindowXP machine (which I call the AmigaExplorer-Host) that has an MOtherboard with OnBoard HD IDE controller.
 I have an IDE Drive, and floppy drive. (MB BIOS picked up the IDE-drive [easy-peasy, no config.sys]
What I did it booted the ADISK floppy in there, and ran Adisk.  It's not ideal but it allows me to play with an IDE Drive with two partions(DOS/AMIGA) just like the MFM drive.

I can PRACTICE with the DISK editor, Disk Doctors.  Learn how to scan raw disk data.   Put some data on there, corrupt partition.  Correct/re-write partition, and see if data structure/Filesystem comes back intact.
I can't put DATA/filesystem or see the AMIGA PARTITION on this PC, but will know how DISK DOCTOR, SCANNING works on it.
(But another crazy thought is load AmigaForever on this PC and see if it can mount the AMIGA partition (#2)) (( WILL THAT WORK?? ))

This learning will have me very prepared with a procedure for attempting to read/dump/clone, fix, rebuild the MFM drive in the Amiga PC (8088 Machine) _>> The only host I can use for the MFM/COntroller Drive.

[wbrejnia]

It seems it reads your Disk geometry correctly, but the fact it does not recognize any partition is a problem.

I remember a version of Ranish caoable of imposing HD to impose manually DOS type when this feature was corrupted, but maybe I was wrong.

Also I do not remember if Verify option in Ranish returns just infos or if it attempts rebuilt corrupted sectors.

With new setup I got to fool around a lot with that spare IDE drive.
Very quick compared to booting Amiga then Amiga pc.

Learning a ton about MBR structure.  Really interesting.

Ranish is useful, mostly for that manual, but can be dangerous if you don't use proper /switches.

Disk Doctor is extremely Dangerous in Auto Mode.

I think Manual DISK Editor will be the key to re-write the Partition Entry of the MBR onto the MFM drive. Getting the first DOS Partition fixed is the bridge to the 2nd AMIGA partition.

What I learned from practice which I wanted to know, is a RAW disk doesn't become a C: drive till the Partition table is there, and the Mode is set to ACTIVE.
And even if c: drive is visible after partition is there, only after format can you do a dir C: on it.
Bootstrap code in the MBR is important for the drive to be bootable.

I think I'll figure this out, but need much more practice.  Data is there so long as I don't format I'm ok.  
Finding the right tool to scan byte by byte will get me my TEXT School paper (I think).  
But it would be fun to restore both Partitions and booth both the PC and the Amiga off the MFM drive.

This is complicated bit-and-byte-wise, but actually simple concepts.


I THINK MY BEST CHANCE would be if I manage to read those two Partition table entries (just the bytes), after many read attempts.  Then write them back to refresh the magnetic byte on the Hard drive.  Even partial recovery would be enough since I have some of the missing pieces knowing the Structure of my DISK.

 Raffaele, I'm not expert (YET), but if you have having boot problems, have you set the IDE drive Partition to Active, and installed  Bootstrap code?

[wbrejnia]

This is what I get when trying to boot from the IDE HDD on the ISA/IDE adapter:

Loefoe,

Does FDISK or ADISK pick up the Drive? (doesn't come back with NO FIXED DISKS message (fdisk), or "READ ERROR" (adisk) ).

If it doesn't pick up then you have a problem of some kind.  

If it does, the ISA/IDE is working properly and another thing needs to be solved..

[wbrejnia]

HARD DRIVE [MBR Master Boot Record] FDISK, ADISK, FORMAT, LOW-LEVEL-FORMAT

Pat, you mentioned that 99.99% of people are no longer interested in Stone age stuff.

We'll I'm the .01% of people that are very interested.


And what's interesting is that the STONE age stuff is still the foundation when it comes to All storage MEDIA, even modern, CF, USB sticks, SSD's etc.  
It is still used by all modern OS's these days (but expanded/improved).


It's all explained here https://en.wikipedia.org/wiki/Master_boot_record

So for my hard drive the first 512 bytes holds everything I need to get access to my data from an OS.

If I can fix the needed info in the first 512 byte of the Hard Drive it will truly come back to life (fully).  May not mean the data is 100% there (I may get read errors on filesystem), but enough to read it via DOS/AMIGA OS (and tools like DISK DOCTOR utilities)

The first 512 Bytes of ANY HARD DRIVE is what makes a DRIVE GOOD (to BIOS on Mother boards and Operating systems).  
GOOD means recognized by FDISK, ADISK and High Level OS FORMAT or LOWER LEVEL (COMPUTER HW BIOS).

I'm glad I never ran the DEBUG Low Level Format (Via WD Card BIOS) since then I'd be screwed (if it de-allocated the sector conataining my 512 Byte MBR).

What I understand (i think), is that the BIOS LOW LEVEL format scans and marks bad sectors on the disk and marks them unusable, and restructures the good sectors.  Thus a low level format would DE-allocate the area of the MFM disk that my partition information is in. (Losing my current MBR).

If the current MBR is not refreshable then then there is no hope to restore the drive to OS readable (as it was). But it doesn't mean I can't still get the data off in RAW format.

I have lots of playing and practice to do on my WinXP machine and the IDE Spare drive.

Stay tuned...more to come.

[wbrejnia]

HARD DRIVE [MBR Master Boot Record] FDISK, ADISK, FORMAT, LOW-LEVEL-FORMAT

Pat, you mentioned that 99.99% of people are no longer interested in Stone age stuff.

We'll I'm the .01% of people that are very interested.


And what's interesting is that the STONE age stuff is still the foundation when it comes to All storage MEDIA, even modern, CF, USB sticks, SSD's etc.  
It is still used by all modern OS's these days (but expanded/improved).


It's all explained here https://en.wikipedia.org/wiki/Master_boot_record
(I believe my HARD Drive has the Structure of a classical generic MBR), but it doesn't matter which  since all Structures have partition info at address=446

So for my hard drive the first 512 bytes holds everything I need to get access to my data from an OS.

If I can fix the needed info in the first 512 byte of the Hard Drive it will truly come back to life (fully).  May not mean the data is 100% there (I may get read errors on filesystem), but enough to read it via DOS/AMIGA OS (an tools like DISK DOCTOR utilities)

The first 512 Bytes of ANY HARD DRIVE is what make a DRIVE GOOD.  
GOOD means recognized by FDISK, ADISK and High Level OS FORMAT.

I'm glad I never ran the DEBUG Low Level Format (Via WD Card BIOS) since then I'd be screwed.

What I understand (i think), is that the BIOS LOW LEVEL format scans and marks bad sectors on the disk and marks them unusable, and restructures the good sectors.  Thus a low level format would DE-allocate the area of the MFM disk that my partition information is in. (Losing my current MBR).

If the current MBR is not refreshable then then there is no hope to restore the drive to OS readable (as it was).  But it doesn't mean I can't still get the data off in RAW format.

[wbrejnia]

I am half way to the Unknown.

So I've been reading and learning, then I started playing.

In a nutshell, I understand partitions and MBR like never before.

I fooled around on the PLAY-PC with the spare IDE-HD.

-----------------------------------------------------------------
I was going to get into the most powerful but dangerous Norton DISKEDIT tools, but I found a interesting Norton tool called Norton DISKTOOL.

DISKTOOL allows you to make a RESCUE (backup copy) of your HardDrive Partition table(MBR), that you can use to load back into the HARD DRIVE if it is every corrupted, or lost.  
(Limitation is that it uses DOS OS to do it, not direct to DISK)

So I created a couple of partitions on the PLAY-PC.

A DOS Partition (using fdisk) and a AMIGA Partition( using adisk).

I formatted the DOS Partition, made it active and There was my C: drive.
I put some files on there that I would recognize.

THEN I RAN Norton DISKTOOL, and made a backup copy of the partition info.

I then DESTROYED the DOS Partition.  No more C: drive.

I ran DISKTOOLS, and ran the Load-back of the Copy, and C: drive came back with all the files I put there.

--------------------------------------------------------------------------------
I tried DISKTOOLS on the AMIGA PC (but it came back with BAD PARTITION INFO).

 So PARTITION information is Corrupt or NOT ALWAYS READABLE.

What I learned is MBR is loaded by DOS at Boot up.

So that is what the LONG BLINK/PULSES on the HardDrive I see at boot.  
I guess Amiga/AmigaPC  try to read MBR, but eventually they give up.  

I got lucky that one time on Boot when MBR got picked up and ADISK saw the partitions.
 (Adisk and Fdisk works through dos, and not directly to the RAW DISK).  Norton DISKEDIT will bypass DOS and go directly to the DISK for the MBR info. (Thus were the power and danger comes into play)

If I did the PARTITION backup  on the Amiga PC when it was good then recovery of the MFM DISK Partitions would be easy.

Actually if I ran DISKTOOL Part. Backup, (that one time the Amiga PC) showed the ADISK info (I could have grabbed a copy of the Partitions), and possibly RE-WRITTEN them back to Refresh the Drive.

-----------------------------------------------------------------
So my plan is to reboot a few times and hope I get lucky again, to be able to get the MFM Parition INfo (via DOS).

IF NOT, then I have to move on to using Norton DISKEDIT, and what I'll do is still unknown (need to learn more), but the plan is to undestand enough an then write MANUALLY the MBR.

[wbrejnia]

** MISSION ACCOMPLISHED -- THE RAW WAY **

WHAT I DESCRIBE IN A FEW LINES below didn't happen in a few seconds, it took some time, some painful idea (Trial & Errors) , and at one point thinking of giving up.

- So I got into Norton DISK Editor after giving up on picking up the MBR rebooting and a few other things.

I played with DISKEDIT and learn there are different kinds of view (HEX, Parition, Bootblock, File Structure, and PLAIN OLD ASCII)

Pretty cryptic stuff for a rookie like me.

-> NORTON DISK EDIT couldn't access the DRIVE THRU DOS (LOGICIAL DISK)
-> But switching to Physical Disk it could read the CYLINDER, SECTORS, etc

---------------------------------------------------------------------------------------------------
I entered the First Partition (DOS), and there was no MBR to read
- As I paged thru the Cylinders there were some unreadable sectors (the First Partition Data has errors)

** BASICALLY the FILESYTEM for DOS Parition is corrupt. **
--------------------------------------------------------------------------------------------------

Then I looked up the ADISK information (that I got that lucky 1 time)  on the AMIGA Parition which starts as CYLINDER 406 (SO I JUMPED TO THAT CYLINDER)


--------------------------------------------------------------------------------------------------- The Amiga Partition looked much better

No Errors reading Cylinder, Sectors etc

I didn't learn much about AMIGA FILE System Structure, so I wasn't go to try to even guess on what to look for.

Then I Switch to Norton ASCII view, and paging through saw a Game Title.

I discovered a ASCII Search Feature and first did a search on my name "WALLY".  
It found a snipet line from something that looked like a Letter head with my Phone #

THEN I GOT AN IDEA.   I searched for the string "68705" which is the Processor I used for my University Paper for the Universal EPROM Programmer.

And there is was..... (MY Thesis Table of Contents )

Found in RAW Ascii Format, using Norton Disk Editor and ASCII Search on the string "68705"

Same string as on my Adapter Module.



Cool



Feels nice that all this work has accomplished something.  (The Missing Thesis Paper)

I got some ideas for next steps, but I can take a well deserve break now.

WallyB

[wbrejnia]

[ Hard Drive - DATA RECOVERY LAB Trial * Needs fine tuning * ]

Man, this next step is complicated!!

I thought I understood things to get the data of the MFM-Hard-Drive.

Basically (I did this with my PLAY-PC to not destroy any data):

Simulating what I would do on the Amiga-PC with MFM-Drive if this worked

1) I SETUP the SPARE IDE-DRIVE (and put some files on it)

2a) The plan was to dump sectors off the IDE-DRIVE on to Floppy (using Norton DISKEDIT dump sector feature TO A FILE)
2b) Then COPY the Floppy (sector dump file) to another computer
3c) This would required many DUMPS since the floppy could only hold 720Kb per dump

- I actually worked (but it didn't work as I expected)
- It didn't dump a file named DUMP onto the Floppy (even though a file appeared doing a "dir a:"
- I actually did a Data Dump into the Floppy (into the same sectors as the SOURCE hard drive being copied)
- THUS it actually DESTROYED the Floppy File system (by overwritting the same sectors taken from the Hard Drive)


The MFM DUMP goal is two possibilities:
---------------------------------------------------------------------------------
1) Just a simple dump that I can use on another better computer to read my School Work
2) Bit more ambitious (but get a dump of the MFM drive) so that I could re-built the AMIGA-PARTION
---------------------------------------------------------------------------------


I need to play more with Norton, since there are so many tools and within each many options.

I also need to look for other tool for Hard Drive Content Dumps (But they need to be small DOS tools that can read a Physical Drive, not logical drive)

------------------------------------------------------------------------------------------------
BTW.  From my scanning, it appears the DOS PARTITION is nearly BLANK (All Zero's).
 It must have been just simple MS DOS Boot Partition (just like the Floppy I'm using now to get the AmigaPC started)
So no need to worry about PARTITION 1. (MS DOS Boot Partition).  ** That I can just install fresh after I get data off Partition 2 **

I bet if I Re-Partition and Format the First Partition to have the AMIGA-PC boot DOS (ie restore the MBR).  
The 2nd AMIGA partition which looks good from SCANNING, may actually POP into existence.

(But too early to try that, since I worry a Format of the FIRST PARTITION, may format into the 2nd Partition if the START and END points of the first partition are incorrect)
-------------------------------------------------------------------------------------

Looking for other DOS based data recovery tools to make this easier.

I mean once I have a copy of the MFM disk (bytes in HEX/ACSII) That is good enough for me to start more risky things.

If anyone knows of some Simple (DOS) HARD DRIVE (RAW Physical-Dump) Tools please pass on.

[wbrejnia]

ACTIVE@ Disk Image for DOS looks promising. (but probably won't work for the AmigaDOS image)

http://disk-image.net/document_dos.htm

But it's good enough to get the RAW Surface image of the MFM drive.

Then I'll need a similar program for the AMIGA (any out there?)