HDD GURU FORUMS

I am wondering what tools are best these days for examining/repairing the surface, if that can be done, and possibly the drive hardware. I have read that some apps can attempt to revitalize the surface by adjusting the write current.

I am working on an old Maxtor 6Y080L0 80 gig drive, just for fun. It is showing read errors around LBA 25,300,000 and there are enough to force chkdsk into a long session.

I have removed all recoverable files from other partitions and reformatted the disk using the Powermax low-level format utility. I re-formatted and added the C: and D: partitions, Chkdsk /r found no problems on C: but has been stuck on D: for over a day, now at 70%. The thing bother me there is that I know the area it is working on is good.

I have a backup for partitions C: and d:, with Win XP on D:. The bad sectors are near the 13 gig mark, putting them in the middle of my XP partition.

The drive boots fine and is recognized by the boot sequence. Powermax has given an error of Y2V SY2.

I know the Maxtor uses a table inside the drive ROM, or on the disk itself, to adjust motor speed and seeking. Is it possible that the bad sectors in one area of the drive could be related to a corrupted drive table?

Spildit wrote:Hello there !

First of all you can't repair the surface of a drive. If the surface have defects and/or the heads are failing then it's time to replace the drive.

Thanks for reply.

I understand and I agree. I have written the drive off and I am working with it only out of curiosity. I am learning a lot going through this exercise.

However, this drive is responding in such a way that I suspect what you said below about firmware/translator problems and/or a bad translator table. At first, I thought it might be a bad partition table but when I ran MHDD it began showing a lot of read errors around LBA 25,300,000 and they eventually caused it to freeze for a long time. I had to terminate the app.

As you say, that is most likely surface defects but it could also indicate a bad translator table or firmware problems.

Another clue. I had several other FAT32 partitions after D:. I had an E:, F:, G: and H:. Drive E: was a small 4 gig swap file partition. F: was readable and I was able to remove all folders and files from it to an external drive. Same with H:. Partition G: was reading fine then suddenly it became unreadable with CRC errors. When I looked at the partition only the first sector was bad.

That's really suspicious and does not sound like a random surface defect. It sounded more like a corrupted partition table, Fat32 table, or a translator issue.

I don't think a bad head is an issue since it can read drive: C fine.

The only reason I ran chkdsk /r was to see if it would mark the bad sectors as bad. If it did, I was going to try building partitions around the bad partition area and hide the partition.

As far as scratches are concerned, I took a drive apart many years ago to see if the heads had landed and scratched the surface. There was not a thing to see. In the old days, I saw the effect of a head crash and it was very apparent.

[quote="Spildit"]As reference on MAXTOR drives the translator sub-system (that translates LBA to internal drive phisical C/H/S location) uses modules U_List, AT_PDL and RZTBL.

Thanks for all the information. I'll need time to absorb it.

Spildit wrote:You might get away with free or pirated tools but up until now i've never saw anyone reporting sucess using those "shaddy" tools, on the contrary. For example for MAXTOR there is a free software to manipulate firmware called HDD Repair 2.0 but all the people that i know that have tried to use that ended up with completly dead drive, so .... don't say that i didn't warn you !

You might notice from my profile that I joined in 2006. Back then I really got into it, going so far as to learn basic Russian. All the good stuff about drives was in Russian. The hardest part was translating Russian slang for drive terminology into English.

I have forgotten most of what I learned but it should come back fast enough. I downloaded a Maxtor manual from this site, which is in Russian, but it has been copy-protected and I can't copy the Russian and put it into Google translator.

I have been an electronics technician and a computer technician for a long time and I have thought about building my own interface, like the PC3000 and writing my own software to communicate with the drive. It would help if someone had already started such a project.

I don't think the interface would be that complex but it might be tougher getting the in-house code the manufacturers use in their BIOS. That could be interrogated using modern debuggers and I know there are many such files floating around.

Spildit wrote:You might want to start by reading some research on VSC like the following :

Thank you kindly for your help and links, Spildit. Very helpful and much appreciated.

I waited till chkdsk had finished it's scan. It was very slow, taking 3 1/2 hours for each 5% of the disk.

It revealed that my formatting was 32K/cluster and it flagged 8 gigs as bad. I am wondering if that means 8 gigs of clusters (allocation units) or 8 gigs measured in sectors.

I reformatted to 4096 sectors/cluster presuming it would be much easier for sector recovery programs to work with the smaller cluster size. NTFS seems to prefer that size anyway. I am using a Hiren's boot disk which has Victoria on it but not MHDD. I have MHDD on a boot CD but it means rebooting to load it. Victoria indicated a large number of bad sector after LBA 32000000.

I have reduced the size of my d: partition to 16 GB, before the errors begin, and after running chkdsk on that, it ran through with no problem. No errors. I am going to try reloading my C: partition, which is a 4 GB with Win98 and my D: drive which has Win XP on it.

Problem is, my D: partition image is 20 gigs so I'm going to try reducing the image size to under 16G.

There's no practical purpose in this other than getting access to disk drive utilities I have on partition C: Also, I have a newer desktop with a fairly recent Intel mobo running XP SP3 which has a spare IDA connector. If I slave the bad Maxtor on the IDA connector I have many utilities on the XP desktop I can use.

Hiren's runs in a ramdisk and I'm hoping my XP with a dual core Intel processor will run faster.

Spildit wrote:Ok then. Good luck and let us know if you manage to make any progress with your drive repairs.

Just one more question. I have another Maxtor 6Y080LO that works. It's a YAR41BW0, If I could find a way to extract the required tables from the good drive, can I swap them with the bad drive?

I know there are rules but I forget the criterion for what each drive needs to have in common.

Old Tech wrote:If I could find a way to extract the required tables from the good drive, can I swap them with the bad drive?

You want to transfer the translator from one drive to another ?
Did I understand your question properly ?

Old Tech wrote:I have been an electronics technician and a computer technician for a long time and I have thought about building my own interface, like the PC3000 and writing my own software to communicate with the drive. It would help if someone had already started such a project.

I think you are vastly simplifying this task in your own mind. Before you should even consider trying to make your own tool, you'd need to spend about ten years working with an existing tool so you actually have some clue as to what these tools do and how complex they are. Then you'd need to study several different fields of programming and engineering. Then you'd need to either spend the next two hundred years reverse engineering every vendor specific command for every hard drive out there or find someone willing to just openly share all this (no one will, they've got too much invested in it).

There is a reason it takes an entire team of engineers and programmers in Russia to produce a tool like PC-3000. To think that one "old tech" is going to pull it off by himself is either pomp or just ignorance.

data-medics wrote:I think you are vastly simplifying this task in your own mind. Before you should even consider trying to make your own tool, you'd need to spend about ten years working with an existing tool so you actually have some clue as to what these tools do and how complex they are. Then you'd need to study several different fields of programming and engineering. Then you'd need to either spend the next two hundred years reverse engineering every vendor specific command for every hard drive out there or find someone willing to just openly share all this (no one will, they've got too much invested in it).

There is a reason it takes an entire team of engineers and programmers in Russia to produce a tool like PC-3000. To think that one "old tech" is going to pull it off by himself is either pomp or just ignorance.

You have misunderstood my questions, they are unrelated. The question about downloading tables from a good, similar drive and uploading to a bad, similar drive was discussed back in the 2006 - 2008 era with someone who was doing it.

I have also traced the entire circuit of a hard drive and I have no difficulty understanding what is going on in the circuit. Back in the old days of computers, in the late 1970's and '80s, I used to replace heads in the field and re-align them using a special disk that had a track dedicated to a signal that could be seen on an oscilliscope. You aligned the heads by watching the amplitude and vertical evenness of the signal.

Mind you, disks only had 1000 tracks per inch in those days and that would be virtually impossible today.

As far as your claim that I am being pompous and ignorant, makes me think you are over-rating the complexity of the electronics and the reverse engineering. I took a look at the HRT board and I find the layout to be modest and very simple. Mind you, I have been working with computers at the hardware level since the 1970s, when processors were made with discrete transistors and hard drives were 18 inches in diameter and held only 5 megabytes of data.

With regard to reverse engineering.... far, far more complex coding has been cracked from manufacturers who were intentionally obfuscating code to protect it and using every imaginable trick to hide it. What they did not count on is that people exist who can do what you claim they cannot.

The hard drive manufacturers have no intention of hiding their codes and not much of it can be stored on the chips on hard drives. Applications can have several megabytes of code to wade through because it is written using a high level language. There is no high level language associated with hard drive code and they don't have the luxury of using extra code to obfuscate their code.

It may take years and years to decipher every code for every hard drive ever made but I am looking only at a Maxtor and there is a lot of information already available on the net for them. As I said, if I do this, it will be for sheer enjoyment, not to go into business.

It is a matter of finding a way to interrogate the chips to retrieve the data then relate that to the hard drive itself. That requires more dogged patience than brilliance.

I have been into reverse engineering for a couple of decades. I never do it for malicious purposes...I never crack a program and release it to the Net. I do it for pleasure, like doing a giant crossword puzzle.

I have reverse engineered a directx program where the mouse input and display is replaced by code from the directX environment. Therefore you cannot access the Windows code directly. That's why in games the screen goes full screen and the mouse cursor appears differently. They belong to the directx code, not the Windows code.

I reversed it by hooking the mouse code and following it back through the Windows system code to where it was connecting to the Windows code. That is infinitely more complex than trying to reverse engineer Assembly code related to a hard drive.

Spildit wrote:Please do read my article about translator here - http://www.hddoracle.com/viewtopic.php?f=46&t=1402 . It should answer your question.

Sorry...I should have stated my question better. I was not talking about translator tables. There are files that can be exchanged between good drives and bad drives if both drives are the same.

Back in the 2006 - 2008 era I was into deep discussions with someone about reviving a hard drive that would not even boot properly. We discussed taking information from a good drive and transferring it to the bad drive.

My memory is foggy but I have extensive notes somewhere that I need to review.

I did visit your site and I was reading a thread on the HRT board.

There was a suggestion that you add a free-wheeling diode to the relay on the board. If the power inputs to the relay coil are isolated from the rest of the circuits on the board, there would be no need for such a diode at 12 volts. There are MOVs used on such boards anyway to absorb transient spikes.

There are only two major chips on your board, both microprocessors. Building that unit would be dead simple electronically, the complexity being the design and mounting of the components.

With regard to the daughter board, it was suggested it is for licensing. Therefore it is what we call a dongle. Every dongle I know of in the real world has been bypassed. The early PC3000 had a dongle that was bypassed.

I don't know why certain manufacturers still insist on such stupid protection. It's used extensively in the music world where software manufacturers use hardware dongles and software protection that can interfere with the rest of your applications. They can even crash your system.

One writer was lamenting that his friend had software that had been cracked to remove the protection yet he was using the purchased product and having headaches over the side effects of the protection software, which kept freezing his app and the entire computer.

It's about greed. The PC-3000 could be purchased at one time in Russia cheaply but a manufacturer in the US got the rights and started charging $10,000. I see they are now down to about $4500.

It's still way too much money. You can buy sound cards that are far more sophisticated and they sell for a few hundred dollars.

I'll build my own if I need one. As another poster claimed, it is beyond someone like me. Let him live in his delusion.

Old Tech wrote:I have also traced the entire circuit of a hard drive and I have no difficulty understanding what is going on in the circuit. Back in the old days of computers, in the late 1970's and '80s, I used to replace heads in the field and re-align them using a special disk that had a track dedicated to a signal that could be seen on an oscilliscope. You aligned the heads by watching the amplitude and vertical evenness of the signal.

I'm an electrical engineer who has plenty of experience as a component level tech. In fact I worked on those same drives (eg Control Data, Ampex, Fujitsu) way back in the 1980s. I well remember those cat's eyes patterns. I wrote my own head alignment program (30 words of machine code) for a Data General minicomputer. This allowed me to use regular software packs instead of expensive CE packs and disc exercisers. Those were fun times.

This was the sort of gear I worked on:

Recovering a ComputerVision CGOS200X file system:
http://www.hddoracle.com/viewtopic.php? ... 203&p=5729

BTW, I would love to see your reverse engineered circuit diagram. Information like that is very hard to come by.

Old Tech wrote:There was a suggestion that you add a free-wheeling diode to the relay on the board. If the power inputs to the relay coil are isolated from the rest of the circuits on the board, there would be no need for such a diode at 12 volts. There are MOVs used on such boards anyway to absorb transient spikes.

Diodes should always be used to protect the switching transistor. Even at 12V, very high back-emf voltages are induced when the relay's coil current collapses. Snubber diodes are just standard practice for any good engineer.

Most of WD's VSCs are documented within the scripts packaged with TREX. This factory tool is all over the Internet, including the HDD Guru files area. That would be a good start.

The only feature of the PC3000 "dongle" that may need to be duplicated is power control and load current monitoring. The former could be achieved with USB controlled relays or similar, while current monitoring may not be necessary if one were to use a current limited supply.

BTW, here is an "IDE Grabber" that you could build:

Reverse Engineering HDD Software using IDE Port Sniffer:
http://www.hddoracle.com/viewtopic.php? ... 611&p=1613

Under certain circumstances you could use a drive's SMART logging feature to sniff and record its own ATA traffic, including VSCs.

fzabkar wrote:Diodes should always be used to protect the switching transistor. Even at 12V, very high back-emf voltages are induced when the relay's coil current collapses. Snubber diodes are just standard practice for any good engineer.

Thanks for reply.

I have no argument with you in the use of snubber, or freewheeling diodes. On the board in question, they seemed to have been omitted and someone suggested adding them to the board. I would reason that someone designing such a board would have a reason for not including them.

Perhaps the relay is driven by a chip that has protection built in. Perhaps the diode is located in a location that is not obvious. I don't know. I did suggest that a common design on modern boards is to employ MOVs to cut off spikes and there are sometimes hundreds of capacitors used all over the board to absorb spikes.

I don't know the reason for omitting the diode, I was only suggesting to the board owner, if the board is working fine, I'd be hesitant to add a snubber diode without fully understanding the operation of the circuits involved. It's not worth blowing a board based on a bad assumption.

fzabkar wrote:Most of WD's VSCs are documented within the scripts packaged with TREX. This factory tool is all over the Internet, including the HDD Guru files area. That would be a good start....
BTW, here is an "IDE Grabber" that you could build:.

Thanks for all the info fzabkar. This is actually a case of data acquisition and storage. I only scanned your link but they send the output to a printer port and it's not clear what they are doing with it. I did notice a picture of what appears to be the trace of a multichannel osciliscope, and they can get pricey.

I was thinking along the lines of capturing a good slice of data and written a program to analyze it. You could single step it into the storage medium to determine which instruction produced which output then you could stream it to gather enough data to get the bigger picture.

Modern microprocessors are very sophisticated but there's nothing to stop anyone using the older TTL logic to build a very simple capture unit like the one at your link.

fzabkar wrote:

Old Tech wrote:I'm an electrical engineer who has plenty of experience as a component level tech. In fact I worked on those same drives (eg Control Data, Ampex, Fujitsu) way back in the 1980s. I well remember those cat's eyes patterns. I wrote my own head alignment program (30 words of machine code) for a Data General minicomputer. This allowed me to use regular software packs instead of expensive CE packs and disc exercisers. Those were fun times.

....BTW, I would love to see your reverse engineered circuit diagram. Information like that is very hard to come by.

I worked on what were called minicomputers like the Datapoint 1100 series through the 5500 series. The lower end units had nothing more than 4 x 8" floppy drives ganged together for a whopping 1 meg of storage. RAM was 4 x 4K boards for a total of 16K. That escalated fairly quickly to 64K then 128K.

I imagine you'll remember the stacked packs of hard drive disks that were 18" in diameter with 5 meg per platter.

I also remember writing realtime programs in Basic to move the heads out to read a certain cylinder on disk.

My circuit diagram is in a major mess. I made no attempt to clean it up. The hardest part was tracing the memory circuitry and trying to identify which chips and components were used.

If I come across the notes I'll try to clean the drawings up and maybe post them.

Old Tech wrote:This is actually a case of data acquisition and storage. I only scanned your link but they send the output to a printer port and it's not clear what they are doing with it. I did notice a picture of what appears to be the trace of a multichannel osciliscope, and they can get pricey.

I was thinking along the lines of capturing a good slice of data and written a program to analyze it.

It has already been done for you. The Grabber includes software that captures the IDE traffic.

http://nazyura.hardw.net/Grabb8b.zip
http://nazyura.hardw.net/Grabb16b.zip

The ZIPs include logs of the taskfile registers.

Old Tech wrote:Perhaps the relay is driven by a chip that has protection built in. Perhaps the diode is located in a location that is not obvious. I don't know.

ISTM that the relay is controlled by 5V logic via a simple NPN transistor. The only reason that I can see for omitting the diode is a possible manufacturing error. Some relays have diodes built-in, but the datasheet would suggest that the board does not employ one of these. Perhaps the design allows for both relay types, in which case it may be that the factory messed up the BOM.

fzabkar wrote:ISTM that the relay is controlled by 5V logic via a simple NPN transistor.

I was researching this question but I have been under the weather the past few days and it's giving me a headache.

Suppose you use a 2N2222. It has a forward current of 1 amp and a reverse breakdown voltage of 40 volts minimum.

The relay is a Rayes RS-12 with a nominal operating current of 12.5 milliamps and a coil voltage of 12 volts.

The question is this...can the induced voltage spike be high enough to exceed the 40 volt reverse breakdown voltage of the 2N2222 transistor? I was trying to find the actual back-EMF generated by a 12 volt coil with no diode across it to bleed off the current produced. I could not find a reference for the inductance of the coil.

fzabkar wrote:It has already been done for you. The Grabber includes software that captures the IDE traffic.

Thanks, fzabkar, that's good to know. I have not been well the past few days and have not done much. Feeling better now.

Old Tech wrote:

fzabkar wrote:ISTM that the relay is controlled by 5V logic via a simple NPN transistor.

I was researching this question but I have been under the weather the past few days and it's giving me a headache.

Suppose you use a 2N2222. It has a forward current of 1 amp and a reverse breakdown voltage of 40 volts minimum.

The relay is a Rayes RS-12 with a nominal operating current of 12.5 milliamps and a coil voltage of 12 volts.

The question is this...can the induced voltage spike be high enough to exceed the 40 volt reverse breakdown voltage of the 2N2222 transistor?

From Wikipedia ...

https://upload.wikimedia.org/wikipedia/commons/7/76/FlybackExample.GIF