2024-12-28

Data clock recovery circuit

DATARECOVERYUNION.COM16 mins

1. A variable phase oscillator comprising:
an oscillator having a substantially fixed frequency output signal;

means for periodically generating coded phase values of said oscillator output signal, said generating means including means for quantizing the phase value of said oscillator output signal into a predetermined number of phase steps;

a source of a prescribed phase value; and

means for comparing said periodically generated coded phase values and said prescribed phase value to periodically generate output pulse signals.

2. The invention as defined in claim 1 wherein the relative phase of said output pulse signals in relationship to said oscillator output signal is dependent on said prescribed phase value.

3. The invention as defined in claim 2 wherein said source of said prescribed phase value includes means for obtaining a phase value which represents the phase difference between said coded phase values and an incoming data transition.

4. The invention as defined in claim 1 wherein said source of said prescribed phase value includes means for obtaining the coded phase value being generated upon occurrence of an incoming data transition.

5. The invention as defined in claim 4 wherein said source of said prescribed phase value includes means supplied with said coded phase values and being responsive to an incoming data transition for storing the coded phase value being generated upon occurrence of said data transition and for adding a predetermined phase value to said stored coded phase value.

6. The invention as defined in claim 4 wherein said source of said prescribed phase value further includes means for adding a predetermined phase value to said obtained coded phase value.

7. The invention as defined in claim 6 wherein said means for obtaining comprises means supplied with said coded phase values and being responsive to said incoming data transition for storing the coded phase value being generated upon occurrence of said data transition.

8. The invention as defined in claim 7 wherein said predetermined phase value is dependent on the incoming data bit period.

9. Data clock recovery apparatus comprising:
an oscillator having a substantially fixed frequency output signal;

means for periodically generating coded phase values of said oscillator output signal, said generating means including means for quantizing said oscillator output signal into a predetermined number of phase steps;

means supplied with said coded phase values and being responsive to an incoming data transition for generating a prescribed phase value in predetermined relationship to a coded phase value being generated upon the occurrence of said data transition; and

means for comparing said periodically generated coded phase values with said prescribed phase value to generate periodically clock recovery pulse signals.

 

10. The invention as defined in claim 9 wherein said means for generating said prescribed phase value includes means supplied with said periodically generated coded phase values and being responsive to an incoming data transition for storing the coded phase value being generated upon occurrence of said data transition and for adding a predetermined phase value to said stored coded phase value.

11. The invention as defined in claim 9 wherein said means for generating said prescribed phase value comprises means supplied with said periodically generated coded phase values and being responsive to an incoming data transition for storing the coded phase value being generated upon occurrence of said data transition and means for adding a predetermined phase value to said stored coded phase value.

12. The invention as defined in claim 11 wherein said coded phase values are coded in a Gray-code format.

13. The invention as defined in claim 11 wherein said predetermined phase value is selected in predetermined relationship to the incoming data bit period.

14. The invention as defined in claim 13 wherein said comparing means generates a clock recovery pulse when said supplied coded phase value equals said prescribed phase value.

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Stored data recovery system

DATARECOVERYUNION.COM112 mins

1. A method for recovering data from a flash data storage system, the method comprising the steps of: loading flash data storage media into a device using a flash data storage system, said device being connected to a technical workstation; loading all physical sectors of the flash data media into memory of the technical workstation or remotely controlling the flash data storage system through hardware/software; whereupon data storage on the flash data storage media can be diagnosed and rectified through operation of the data recovery computer portion of the technical workstation.

2. The method as defined in claim 1, further including the step of querying a flash data storage system for information through operation of a data recovery program by the technical workstation prior to loading sectors onto the data recovery computer portion of the technical workstation.

3. The method as defined in claim 2 wherein said step of querying said flash data storage system includes determining at least one of: the PC card type, the memory size, PC card geometry, chip type, firmware revision, and type of card.

4. The method as defined in claim 2, further including the step of querying the flash data storage system for identifying information through operation of a data recovery program by the technical workstation prior to loading all physical sectors of the flash data media into memory of the technical workstation.

5. The method as defined in claim 4 wherein the step of querying the flash data storage system for identifying information further includes the step of checking socket status for write protection and the status of the backup battery on the flash data storage system.

6. The method as defined in claim 2, wherein the step of identifying the flash data storage system includes monitoring the flash data storage medium containing the data recovery application programs.

7. The method as defined in claim 1 further including the step of executing a data recovery application program on the flash data storage system.

8. The method as defined in claim 7 wherein the step of executing a data recovery application program further includes the step of computing a CRC checksum over an entire PC card or section thereof.

9. The method as defined in claim 1, further including the step of executing a data recovery diagnostic program on the flash data storage system.

10. The method as defined in claim 9 wherein the step of executing a data recovery diagnostic program includes the step of generating DOS-Formats for SRAM and ATA cards.

11. The method as defined in claim 1, further including the step of downloading data to be recovered from the flash data storage system to said technical workstation.

12. The method as defined in claim 1, further including the step of logging all write activity, to be performed on a sector of the flash data storage media to a file on said technical workstation.

13. The method as defined in claim 12, further including the step of providing each entry within the file with an identifier which identifies the sector and the local storage device, as well as the latest data which was written to that sector.

14. A data recovery system for recovering inaccessible data from a flash data storage system, comprising: a flash data storage system selected from a group including: CompactFlash, ATA Type I, II, III or IV, digital film card, SmartMedia, Memory Stick, Multimedia Card (MMC), Secure Digital Card (SD) or other similar flash device; a data recovery system including a computer which computer accesses or controls the flash data storage system so that data on the flash data storage media of the flash data storage system can be diagnosed and rectified.

15. A data recovery system as defined in claim 14, further including a technical workstation which includes a second data storage media for storing data recovery application program means.

16. A data recovery system as defined in claim 14, further comprising a communications channel over which communications are established between the flash data storage system and the technical workstation, said communications channel using one of the group including a PCMCIA Adapter, Floppy type adapter, local area network, wide area network, Internet and proprietary adapter suited to the flash storage device.

17. A data recovery system as defined in claim 14, wherein the flash data storage system is operable from said data recovery computer so as to recover data from the flash data storage media.

18. A data recovery system as defined in claim 14, wherein a flash data storage device is operable from the data recovery computer so as to diagnose a data recovery situation on the flash data storage media.

19. A data recovery system for recovering inaccessible data from a flash data storage system to another flash data storage system, said data recovery system comprising: a flash data storage system selected from a group including: CompactFlash, ATA Type I, II, III or IV, digital film card, Smart Media, Memory Stick, Multimedia Card (MMC), Secure Digital Card (SD) or other similar flash device; a computer which accesses or controls the flash data storage system so that data on the flash data storage media can be diagnosed and rectified.

20. The data recovery system as defined in claim 19 further including: a communication channel over which communications are established between the flash data storage system and another flash data storage system, said communications channel using one of the group including an PCMCIA Adapter, a Floppy type adapter, local area network, wide area network, Internet, and proprietary adapter suited to the flash storage system.

21. A method for recovering data from a flash data storage system, the method comprising the steps of: establishing a data link between a technical workstation and a flash data storage media through operation of a data recovery application program by a technical workstation; and controlling flash data storage by a technical workstation; whereupon data on the storage media of the flash data storage system can be diagnosed and rectified through operation of said technical workstation.

22. A data recovery system as defined in claim 21, further including means for transferring all data, which is marked for being changed to an archival facility before making the changes to the flash card data storage media.

23. A data recovery system as defined in claim 21, further including means for logging all write activity, to be performed on a sector of a local storage device, or to a file on the flash card data storage media.

24. A data recovery system as defined in claim 21, wherein each entry within the file contains an identifier, said identifier identifying the sector and the local storage device, as well as the latest data which was written to that sector.

25. A data recovery system as defined in claim 21, further including means to select data recovery events during a data recovery process.

26. A method of data recovery comprising the steps of: establishing a communications link between a flash data storage system requiring recovery of data and a data recovery computer; enabling interaction between said flash storage system and said data recovery computer; diagnosing said flash data storage system; downloading a data recovery application program from said data recovery computer to said flash data storage system; and recovering data on the flash storage system.

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Background of the Magnetic disc drive head alignment system Invention

DATARECOVERYUNION.COM06 mins

Magnetic disc drives for recording digital data are well known to the art. In such drives it is desirable to achieve the highest recording density possible, such recording density being a function of both the number of annular tracks per radial inch of disc surface and the number of bits per inch along each track. The optimum number of tracks on the individual discs is dependent on the precision of the head positioning system and on the precision in the alignment of the various read/write heads in the disc drive. The system of the present invention provides for the precise alignment of each of the read/write heads in the disc drive so that an optimum number of tracks per radial inch of the individual discs may be achieved.

The discs incorporated into present-day disc drives are usually referred to as a disc pack, and these discs are stacked one above the other to be sensed by a plurality of magnetic read/write heads mounted in vertical alignment and positioned by a single actuator. In one type of present-day head positioning system used in disc drives, one of the heads (servo disc surface) and one disc surface are dedicated to the generation of debit position signals for an associated servo system. A plurality of servo tracks are recorded in concentric circles on the dedicated servo disc surface, and the servo head produces the debit signals which are indicative of the relative position of the servo head and the servo tracks.

For interchangeability of the disc packs, the various tracks recorded on each of the disc surfaces must be closely aligned with the pre-recorded servo tracks on the dedicated servo disc surface so that the read back of the data from each disc pack is possible on recorders other than the one on which the data was recorded.

When the servo head is held in registry with the servo tracks on the dedicated servo disc surface, and the remaining read/write heads are aligned with the servo head, the remaining heads will be properly positioned over the corresponding data tracks on other disc surfaces. As mentioned above, an objective of the present invention is to provide a system which enables the remaining magnetic heads to be precisely aligned with the servo head, so that they will all be properly positioned with respect to the data tracks on the other disc surfaces.

The normal procedure for assuring that the read/write heads are in vertical alignment is to place a disc pack into the disc drive which has pre-recorded and precisely positioned servo tracks on all the disc surfaces. Such pre-recorded servo disc packs are commercially available for use in head alignment and are usually referred to as “CE” (Customer Engineer) packs. By reading the signals from the individual heads, as the heads read the various servo tracks, and by feeding such signals to a display device, each head can be adjusted until it is in precise tracking engagement with the tracks on the surface of the corresponding disc.

The present invention, as mentioned above, provides a system for reading debit signals generated by the various heads of a disc drive, as these heads read the various servo tracks on the pre-recorded servo disc pack, and it provides digital outputs representative of any misalignments of the various heads. Each head can then be adjusted to a position at which the digital output signal for that head indicates precise alignment.

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Magnetic disc drive head alignment system

DATARECOVERYUNION.COM06 mins

hard disk alignment1. In a disc drive which includes a plurality of read/write magnetic heads and a servo magnetic head mounted for simultaneous movement by an actuator in response to a servo signal from the servo head, and in which the positions of the read/write heads are individually adjustable with respect to the servo head, a system for indicating any misalignment of the individual read/write heads as the particular head produces a cyclic position signal in response to position signals pre-recorded on alignment tracks of an alignment disc, each cycle of said cyclic position signal having a first segment with positive and negative peak amplitudes and a second segment with positive and negative peak amplitudes, the positive and negative peak amplitudes of said first and second segments being equal when the particular head is in registry with the corresponding alignment track, and the positive and negative peak amplitudes of one or the other segments decreasing when the particular head moves out of registry with the alignment rack to one side or the other thereof; said system including balanced gating circuitry having four output circuits for respectively producing four gating signals respectively timed to occur in time coincidence with respective ones of the positive and negative peak amplitudes of said first and second segments; a balanced input circuit connected to the particular head and including first and second outputs respectively applying the cyclic position signal and its complement to said gating circuitry to cause said gating circuitry to cause said gating circuitry to produce said four gating signals at the respective output circuits thereof; peak detector circuitry including four peak detector circuits respectively connected to said four output circuits of said gating circuitry to be individually gated by respective ones of said four gating signals, means connecting two of said peak detector circuits to the first output of said balanced input circuit and further means connecting the other two of said peak detector circuits to the second output of said balanced input circuit, said four peak detector circuits collectively detecting the positive and negative peak amplitudes of each of the two segments of each cycle of said position signal and providing four analog outputs corresponding thereto; and output circuitry connected to the outputs of said four peak detector circuits in said peak detector circuitry for producing an analog output signal having an amplitude corresponding to the difference between the algebraic sum of the positive and negative peak amplitudes of the first segment and the algebraic sum of the positive and negative peak amplitudes of the second segment.

2. The system defined in claim 1, in which said balanced input circuit includes a linear amplifier, and in which said system includes a summing circuit connected to said four peak detectors in said peak detector circuitry for producing an output signal representing the algebraic sum of the outputs of the four peak detector circuits, and an automatic gain control circuit connected to said summing circuit and responsive to the output thereof for producing an automatic gain control signal for said linear amplifier.

3. The system defined in claim 1, in which said gating circuitry contains a frequency-independent phase-shifting circuit so that the system may be used with a wide variety of recorded signals without adjustment.

4. The system defined in claim 1, and which includes circuitry connected to said peak detector circuitry for limiting the analog outputs thereof to a predetermined maximum.

5. The system defined in claim 1, and which includes an analog/digital converter coupled to the output of said output circuitry to convert the analog output signal therefrom into a corresponding digital signal; and a digital display device coupled to the output of the analog/digital converter.

6. The system defined in claim 1, in which said gating circuitry includes first and second comparators interconnected to provide a quadrature shift to the cyclic position signal from said balanced input circuit which is independent of frequency.

 

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WD Passport – DML file extension – Encrypted files?

DATARECOVERYUNION.COM17 mins

Problem: Copied all data from source PC to the Passport, then deleted the data from the source PC. When the Passport was next connected to the source PC it synced and deleted the data from Passport as well.

A lot of deleted data from the Passport have been recovered; however, the data in terms of file names and reported size but they are all .DML files. They cannot be opened by conventional methods or by changing the file ext. Is this a proprietary WD encryption format?

Solution: First things first: If you thought you had a secure backup of your data on a WD Passport and you plugged it into a computer that crashed/fried/etc. and planned to copy your lost files to your fixed-up PC from your WD Passport and found yourself (as another blogger said somewhere) like a deer in the headlights as you watched in horror as the WDSync software automatically started syncing your newly blank internal drive (or empty folders on your internal drive) and the Passport, thus “removing” all your “backed up” files from your Passport, you are not alone (and you’re not stupid).

DO NOT save ANYTHING to the Passport. The files are not gone yet because they have not been overwritten. They are “deleted” files, which typically could be recovered with some free recovery software from download.com, but alas, they are also encrypted, so just recovering them won’t help you. You also have to decrypt them (DMailer uses AES 128-bit encryption).

If you are computer savvy…you should realize that the WDSync software is not backup software and is, in fact, just syncing software. So, if you delete something from your desktop it will delete it from the Passport as well, next time you sync. However, EVEN IF you are computer savvy, you probably wouldn’t have guessed in a million years that DMailer would make “autosync” the default setting and that they wouldn’t tell you ahead of time or prompt you in some way before it started deleting files. So, if you want to use WDSync to sync your data between your computer and your Passport, before you do anything else, SHUT OFF autosync and always manually sync. If you are not interested in syncing your data and just want to backup your data, skip the WDSync software all together. Don’t use it. Just use the Passport like a jump drive and drag and drop your files to it. Your data won’t be encrypted or password protected, but download.com offers a number of downloads that will do this for you (specifically for external drives, jump drives, etc.).

If you are not computer savvy…don’t use the WD Sync software. Do what I just said. Drag and drop your files to the WD Passport as if it were just a jump drive. This way your data are backed up and you can delete whatever you want from wherever you want without worrying about all your data suddenly vanishing.

The headlights for the precious files disappear:

(1) Again, DO NOT save anything to the WD Passport after this happens or your files could be gone for good.

(2) Email DMailer (the company that makes WDSync software for Western Digital). Do NOT contact Western Digital, they will just tell you are screwed. WD’s customer support is awful. Go to http://www.dmailer.com and tell DMailer you just accidentally removed encrypted files from your passport that you need to recover.

(3) Just for kicks, ran some recovery software and turned up a lot of .dml files, but you shouldn’t have to use recovery software if you haven’t overwritten your files. Double click on the Passport icon to open the drive. Find the “WD Sync Data” folder. Open the folder for the computer you accidentally synced to (e.g., “office computer”). Open the “Data” folder. There you should find the .option file, the data base file and a folder containing the “deposited” files from the latest sync. In the Sync deposit folder are more folders which should contain the DMailer files (.dml).

(4) Wait for DMailer to get back to you with their data recovery tool.

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How you should deal with the hard disk which contains important data

DATARECOVERYUNION.COM12 mins

If you have problems with a hard disk which contains important (valuable) data:

* any kind of manipulation with the hard disk or with software could hinder data retrieval or could cause an enormous increase of the retrieval costs.

* do not use any software, even if some guys (internet) told you to do so

* do not run chkdsk or defragmentation, even if you are told to do so

* do not open a hard disk if you don’t have the knowledge, training and the tools (even then you may expect to lose the data)

* contact a (local) DR company; supply them with complete information

* perhaps some data recovery forum could guide you to find the right Data Recovery company

Four solutions for you:
1. you are the typical user who knows all better than a pro – then try DIY – it’s your data

2. you store your hdd in a safe place for some time – until you got the money

3. you put the hdd into the garbage – you will stay poor and won’t get enough money

4. you look for a pro – even here in the data recovery forum – get an estimate on “money for data basis”

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How to remove Seagate Momentus 5400.4 password

DATARECOVERYUNION.COM42 mins

You can do it with SE_DIV http://sediv2008.narod.ru/Easy1014.rar
Choose Family=Momentus 5400.4
Model=your model
COM=your COM
press Connect and insert power to hdd.
You’ ll see IN COM Shell:
—————–
Reset
4096k x 16 DRAM
CORSAIR – 1_Disk S-00 11-08-07_16:25

Buzz HM SFI
!
(P)SATA Reset
(H)SATA Reset
——————
press Ctrl-Z

You’ ll see
—————-
…
T>
—————
Go to Read/Write
press button Full Detect
You’ ll see

SPT = 337
remember it.
Go to Read SA
Type System Tracks
Type Checked All
Press Detect

You’ll see
PLEAS READ ALL CAREFULLY BEFOR START:

1) Push button OK.
2) Turn Off Power HDD.
3) Wait HDD speed down until stop one.
Pause during 5-10 seconds.
4) Turn On Power HDD.

Do it!
You’ll see
Vendor Track = F91D
remember it
Go to Read/Write
Type Read Sectors
Begin Track=F91D
Head=0
Begin Sector=6
Sector Count=7
Buffer Adr.=4B0

press Read
and attach your Trk_F91D Hd_0 Sct_6(7).bin

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Resolve O LBA, Seagate 7200.11 BIOS don’t recognize (Part II)

DATARECOVERYUNION.COM04 mins

PART 2

If your HDD 7200.11 is not recognize by BIOS,

and after you connect him to COM1 and turn on power if you have this response for any command like:

Rst 0x10M
LED:000000CC FAddr:0025BF67
Ctrl + Z
F3 T>
LED:000000CC FAddr:0025BF67
your drive is busy!

power off your Hdd
slightly unscrew one screw near to motor connection to PCB and put plastic visit card! Or you can remove PCB.
Effect is the same…
power on your hdd,

Ctrl +Z

F3 T>/2
F3 2>
F3 2>Z

Spin Down Complete
Elapsed Time 0.138 msecs
F3 2>

now you put PCB back, or pull visit card
enter this
F3 2>U
Spin Up Complete
Elapsed Time 7.242 seconds
F3 2>

F3 T>/1
F3 1>N1
this is a S.M.A.R.T. erase

after that POWER off HDD, it means that you plug off power to hdd,
power on hdd,
reenter
CTRL+Z on terminal
F3 T>i4,1,22
this is G-list erase

after that POWER off HDD, it means that you plug off power to hdd,
reenter
CTRL+Z on terminal
F3 T>m0,2,2,0,0,0,0,22 Enter

!!!IMPORTANT, don’t turn hdd power off, or comp off, wait about 30 sec to 2 minutes until it finished!!!

then you see something like this.

Max Wr Retries = 00, Max Rd Retries = 00, Max ECC T-Level = 14, Max Certify Rewrite Retries = 00C8 Max retries Wr = 00, Max Rd retries = 00, Max T-ECC Level = 14, Max certify Rewrite retries = 00C8
User Partition Format 10% complete, Zone 00, Pass 00, LBA 00004339, ErrCode 00000080, Elapsed Time 0 mins 05 secs User Partition Format 10% complete, Zone 00, Pass 00, LBA 00004339, ErrCode 00000080, Elapsed Time 0 mins 05 secs
User Partition Format Successful – Elapsed Time 0 mins 05 secs User Partition Successful Format – Elapsed Time 0 mins 05 secs

After that hit

F3 T>/2
and
F3 2>Z
Spin Down Complete
Elapsed Time 3.038 msecs

Turn off power from your HDD, od shutdown your comp.

That’s all!

WARNING: Please do NOT try this if you have valuable data on your drive. Do not blame anyone if something goes wrong. You do it at your own risk. Remember that if something goes wrong, it is extremely unlikely that anyone will be able to help you remotely. One wrong command via terminal could easily result in a completely bricked HDD (I really do mean bricked = no one will be able to recover it, even Seagate).

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Resolve O LBA, Seagate 7200.11 BIOS don’t recognize (Part I)

DATARECOVERYUNION.COM05 mins

This tutorial is not for inexperienced users!!! Do NOT POWER OFF YOUR hdd, computer, during it, (EXCEPT IF I SAY SO)and you just to be sure connect your computer to UPS.

First you must have to build serial rs232 converter to TX,RX GND, you can use any data cable from your cell phone from Siemens 35 series custom build data cable buid on this picture with max232. Be sure that you put zener diode 2V7 at the picture..Because you could burn your Tx, Rx, on HDD-s PCB.

So, when you build, get your adapter, connect it to this pins on Seagate drive.
[ ”””””””’| |””””’ ] [ .. ..] —-> Rx.. Tx
You do not need to connect SERIAL-ATA CABEL
open hyper terminal or another type of terminal select Serial port example “COM1”
set bit rate to 38400bps
data bits 8
parity N
stop bits 1

it’s default settings except bps.
plug power to disk and after that you will see on terminal something like this:

PART 1

Rst 0x10M
hit Ctrl + Z to get “prompt”
F3 T>

now, if your BIOS recognize disk but there is 0 LBA,0 capacity

all you need is to hit this command:

F3 T>m0,2,2,0,0,0,0,22 Enter

!!!IMPORTANT, don’t turn hdd power off, or comp off, wait about 30 sec to 2 minutes until it finished!!!

then you see something like this.

Max Wr Retries = 00, Max Rd Retries = 00, Max ECC T-Level = 14, Max Certify Rewrite Retries = 00C8 Max retries Wr = 00, Max Rd retries = 00, Max T-ECC Level = 14, Max certify Rewrite retries = 00C8
User Partition Format 10% complete, Zone 00, Pass 00, LBA 00004339, Err Code 00000080, Elapsed Time 0 minutes 05 seconds User Partition Format 10% complete, Zone 00, Pass 00, LBA 00004339, Err Code 00000080, Elapsed Time 0 minutes 05 seconds
User Partition Format Successful – Elapsed Time 0 minutes 05 seconds User Partition Successful Format – Elapsed Time 0 minutes 05 seconds

After that hit

F3 T>/2
and
F3 2>Z
Spin Down Complete
Elapsed Time 3.038 msecs

Turn off power from your HDD, od shutdown your computer.

WARNING: Please do NOT try this if you have valuable data on your drive. Do not blame anyone if something goes wrong. You do it at your own risk. Remember that if something goes wrong, it is extremely unlikely that anyone will be able to help you remotely. One wrong command via terminal could easily result in a completely bricked HDD (I really do mean bricked = no one will be able to recover it, even Seagate).

WARNING: Please do NOT try this if you have valuable data on your drive. Do not blame anyone if something goes wrong. You do it at your own risk. Remember that if something goes wrong, it is extremely unlikely that anyone will be able to help you remotely. One wrong command via terminal could easily result in a completely bricked HDD (I really do mean bricked = no one will be able to recover it, even Seagate).

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