|
Home / Computers / Data Recovery
Compact Flash Memory and Data Recovery
By:Bharat Bista
Flash memory gets its name due to its microchip arrangement in such a way, that its section of memory cells gets erased in a single action or "Flash".
Both NOR and NAND Flash memory were invented by Dr. Fujio Masuoka from Toshiba in 1984.The name 'Flash' was suggested because the erasure process of the memory contents reminds a flash of a camera, and it's name was coined to express how much faster it could be erased "in a flash". Dr. Masuoka presented the invention at the International Electron Devices Meeting (IEDM) held in San Jose, California in 1984 and Intel recognizes the potentiality of the invention and introduced the first commercial NOR type flash chip in 1988, with long erase and write times.
Flash memory is a form of non-volatile memory that can be electrically erased and rewrite, which means that it does not need power to maintain the data stored in the chip. In addition, flash memory offers fast read access times and better shock resistance than hard disks. These characteristics explain the popularity of flash memory for applications such as storage on battery-powered devices.
Flash memory is advance from of EEPROM (Electrically-Erasable Programmable Read-Only Memory) that allows multiple memory locations to be erased or written in one programming operation. Unlike an EPROM (Electrically Programmable Read-Only Memory) an EEPROM can be programmed and erased multiple times electrically. Normal EEPROM only allows one location at a time to be erased or written, meaning that flash can operate at higher effective speeds when the systems using; it read and write to different locations at the same time.
Referring to the type of logic gate used in each storage cell, Flash memory is built in two varieties and named as, NOR flash and NAND flash.
Flash memory stores one bit of information in an array of transistors, called "cells", however recent flash memory devices referred as multi-level cell devices, can store more than 1 bit per cell depending on amount of electrons placed on the Floating Gate of a cell. NOR flash cell looks similar to semiconductor device like transistors, but it has two gates. First one is the control gate (CG) and the second one is a floating gate (FG) that is shield or insulated all around by an oxide layer. Because the FG is secluded by its shield oxide layer, electrons placed on it get trapped and data is stored within. On the other hand NAND Flash uses tunnel injection for writing and tunnel release for erasing.
NOR flash that was developed by Intel in 1988 with unique feature of long erase and write times and its endurance of erase cycles ranges from 10,000 to 100,000 makes it suitable for storage of program code that needs to be infrequently updated, like in digital camera and PDAs. Though, later cards demand moved towards the cheaper NAND flash; NOR-based flash is hitherto the source of all the removable media.
Followed in 1989 Samsung and Toshiba form NAND flash with higher density, lower cost per bit then NOR Flash with faster erase and write times, but it only allows sequence data access, not random like NOR Flash, which makes NAND Flash suitable for mass storage device such as memory cards. SmartMedia was first NAND-based removable media and numerous others are behind like MMC, Secure Digital, xD-Picture Cards and Memory Stick. Flash memory is frequently used to hold control code such as the basic input/output system (BIOS) in a computer. When BIOS needs to be changed (rewritten), the flash memory can be written to in block rather than byte sizes, making it simple to update.
On the other hand, flash memory is not practical to random access memory (RAM) as RAM needs to be addressable at the byte (not the block) level. Thus, it is used more as a hard drive than as a RAM. Because of this particular uniqueness, it is utilized with specifically-designed file systems which extend writes over the media and deal with the long erase times of NOR flash blocks. JFFS was the first file systems, outdated by JFFS2. Then YAFFS was released in 2003, dealing specifically with NAND flash, and JFFS2 was updated to support NAND flash too. Still, in practice most follows old FAT file system for compatibility purposes.
Although it can be read or write a byte at a time in a random access fashion, limitation of flash memory is, it must be erased a "block" at a time. Starting with a freshly erased block, any byte within that block can be programmed. However, once a byte has been programmed, it cannot be changed again until the entire block is erased. In other words, flash memory (specifically NOR flash) offers random-access read and programming operations, but cannot offer random-access rewrite or erase operations.
This effect is partially offset by some chip firmware or file system drivers by counting the writes and dynamically remapping the blocks in order to spread the write operations between the sectors, or by write verification and remapping to spare sectors in case of write failure.
Due to wear and tear on the insulating oxide layer around the charge storage mechanism, all types of flash memory erode after a certain number of erase functions ranging from 100,000 to 1,000,000, but it can be read an unlimited number of times. Flash Card is easily rewritable memory and overwrites without warning with a high probability of data being overwritten and hence lost.
In spite of all these clear advantages, worse may occur due to system failure, battery failure, accidental erasure, re-format, power surges, faulty electronics and corruption caused by hardware breakdown or software malfunctions; as a result your data could be lost and damaged.
Flash Memory Data Recovery is the process of restoring data from primary storage media when it cannot be accessed normally. Flash memory data recovery is a flash memory file recovery service that restores all corrupted and deleted photographs even if a memory card was re-formatted. This can be due to physical damage or logical damage to the storage device. Data even from damage flash memory can be recovered, and more than 90% of lost data can be restored.
Digg
del.icio.us
Blink
Stumble
Spurl
Reddit
Netscape
Furl
Article keywords: Compact Flash Memory, Data Recovery
Article Source: http://www.articles2k.com
Author : Bharat Bista
Digital Image Recovery
eProvided.com
Bharat Bista is an Independent SEO consultant, specializing in Search Engine Optimization and eCommerce advancement. In addition is a professional business article writer in compound subjects.
|
|
| Top Data Recovery Articles |
|
|
- 2). XCACLS, SUNINACL, And Other Permissions Security Recovery Tools By : Darren Miller
You Have 50GB Of Data To Move Along With Permissions Security
----------------------------
This article is about several tools that can save a Windows administrators you know what in the event of a large scale permissions security problem.
Here is a fictional scenario we can use to illustrate the use of the XCACLS tool. We need to move or copy 50GB worth of data that is comprised of several thousand directories containing hundreds of thousands of small files from one storage system to another.
|
|
|
- 4). Hard Disk Failure and Data Recovery By : Bharat Bista
Hard Disk: An Introduction
Hard disk is a non-volatile data storage device that stores electronic data on a magnetic surface layered onto hard disk platters. Word Hard is use to differentiate it from a soft, or floppy disk. Hard disks hold more data and can store from 10 to more than 100 gigabytes, whereas most floppies have a maximum storage capacity of 1.
|
- 5). How To Recover Data Or Survive A Hard Disk Disaster By : frank vanderlugt
Disk failure occurs when a hard disk drive no longer operates and the information on it can no longer be accessed by the computer.
This can happen for no reason at all or due to an external factor such as exposure to fire or water or High Magneticwaves or suffering a sharp impact
How seriously the disk failure is varies.
|
- 6). Data Recovery - It May Not be to Late After All By : Tyson J Stevenson
The salvaging of lost data or making available the previously damaged data stored on various damaged media such as hard disk drives, magnetic tapes, magnetic disks, zip disks, CD-Rom, flash cards and other storage media is known as Data recovery.
|
- 7). Data Recovery - What To Do When Your Hard Drive Fails By : Jim Grayson
How many times have you experienced that sickening feeling when your hard drive suddenly fails? How many times have you experienced that your hard disk just does not boot and all the data may be gone forever? A hard drive failure is one of the most common problems and worst nightmares faced by computer operators all over the world. Precious data is lost either at home or in big corporate environments.
|
- 8). Can USB Data Recovery Be Recovered? By : Chelsea Aubin
When you store important information on a USB device, you take the chance of losing that information. Losing data on a USB can be kind of a mystery, but there are companies out there that can help you get that data back. These companies use engineering that can recover your lost data over ninety six percent of the time. These companies can even recover data that has been stored on a damaged USB device.
|
|
|
- 10). Compact Flash Memory and Data Recovery By : Bharat Bista
Flash memory gets its name due to its microchip arrangement in such a way, that its section of memory cells gets erased in a single action or "Flash".
Both NOR and NAND Flash memory were invented by Dr. Fujio Masuoka from Toshiba in 1984.The name 'Flash' was suggested because the erasure process of the memory contents reminds a flash of a camera, and it's name was coined to express how much faster it could be erased "in a flash".
|
| New Data Recovery Articles |
- 1). PC Crash! How To Find The Best Data Recovery Consultant By : Stu Pearson
Everyone’s PC crashes now and again. So what can you do after that dreaded crash? Hire a Data Recovery Consultant.
You wouldn’t let somebody throw away important documents or files of yours, would you? Well, don’t let your computer get away with that either. Even if your business has backup files, your data is still at risk of deletion. That is why it’s nice to have a Data Recovery Consultant on your side.
|
- 2). Data Recovery Procedures For Hard Drives By : Stu Pearson
Your computer’s data is at risk. Whether you use a Mac or a PC, viruses, power surges, hackers, human error, natural disasters, hardware failures, and more are real everyday threats. To keep your data safe and sound, you will first need to back up your files on a regular basis. Secondly, when hard drive failure does occur, data recovery is the only solution.
|
- 3). Data Recovery Services: What To Do When Your Hard Drive Fails By : Stu Pearson
According to most people, there are two types of hard drives: those that have failed and those that will fail. But for folks who use Data Recovery Services, there is a third type of hard drive: one that does not fail.
A hard drive is the most vulnerable part of a computer; it has moving gears and is hence prone to wear and tear. So when you need hard disk data recovery, you must deeply consider the service and practice of the various repair companies in your area.
|
- 4). Data Recovery and Your Computer By : Kathy Crawford
Have you ever wondered if what you know about data recovery is accurate? Consider the following paragraphs and compare what you know to the latest info on data recovery.
Sooner or later your company could become the victim of a natural disaster, or something much more common like a lightning storm or downed power lines.
Just because your company may be a small business doesn't mean it's immune to data disasters.
|
- 5). Consequences of data loss and Why should Offsite Backup be used By : Mozza
There is a calculated trend in all business corporations and firms: when the enterprise is getting bigger, its support of data increases its complexity, volume and value. The larger your enterprise is, the more significant your data files become. The traditional tape backup can no longer produce in-depth data information about all the important features of your business.
|
- 6). The Drama of Data Recovery By : Khieng Chho
Data loss is often a tragic and traumatic experience for most computer users. It is often due to hard drive failure, accidental formatting, electronic malfunctioning or a product of "natural calamities". This seems to be not much of a problem when there are viable data back-ups that the user creates. However, the problem comes when we tarry on making our back-up files, which is not a rare practice by the way.
|
- 7). Data Recovery - What To Do When Your Hard Drive Fails By : Jim Grayson
How many times have you experienced that sickening feeling when your hard drive suddenly fails? How many times have you experienced that your hard disk just does not boot and all the data may be gone forever? A hard drive failure is one of the most common problems and worst nightmares faced by computer operators all over the world. Precious data is lost either at home or in big corporate environments.
|
- 8). Can USB Data Recovery Be Recovered? By : Chelsea Aubin
When you store important information on a USB device, you take the chance of losing that information. Losing data on a USB can be kind of a mystery, but there are companies out there that can help you get that data back. These companies use engineering that can recover your lost data over ninety six percent of the time. These companies can even recover data that has been stored on a damaged USB device.
|
- 9). Secrets of Microsoft new file system revealed by Data Recovery Engineer By : Hugo Galilea
Hi friends, let’s talk this time about the new concept in file manager that will be introduced by Microsoft in its new Operating system Windows Vista. The name of this new file administration is “WinFS”.
WinFS is a new file system that it’s being developed by Microsoft to be used in its new operating system Windows Vista. At the begining this name means Windows Future Storage, but now is only Windows File System.
|
- 10). Compact Flash Memory and Data Recovery By : Bharat Bista
Flash memory gets its name due to its microchip arrangement in such a way, that its section of memory cells gets erased in a single action or "Flash".
Both NOR and NAND Flash memory were invented by Dr. Fujio Masuoka from Toshiba in 1984.The name 'Flash' was suggested because the erasure process of the memory contents reminds a flash of a camera, and it's name was coined to express how much faster it could be erased "in a flash".
|
|
|
