4GB memory card recovery,recover data from 4GB memory card
- Publish Time：2018-09-25 08:47
4GB memory card
4GB SD card memory card is an independent storage medium used in mobile phones, digital cameras, portable computers, MP3s and other digital products. It is usually in the form of cards, so it is collectively called "memory card", also known as "digital memory card". , "Digital Memory Card", "Memory Card", etc.
4GB Memory card
Due to the large size of the traditional CF card, Infineon and SanDisk jointly launched a new memory card product MultiMedia Card (MMC card) in 1997. The size of the MMC card is 32mm × 24mm × 1.4mm, with a 7-pin interface, no read/write protection switch. Mainly used in digital cameras, mobile phones (such as Siemens MP3, mobile phone 6688), and some PDA products.
It is a memory card designed by the MMC Association in 2002 for multimedia products such as mobile phones. RS-MMC is much smaller than MMC, and it can be converted to a standard MMC card with a dedicated adapter.
In September 2004, the MMC Association introduced MMC PLUS and MMC moboile. The MMC PLUS card has the same size as a regular MMC card and has a faster reading speed. Some factory businesses have also introduced low-voltage MMC PLUS.
In order to obtain better power-saving performance, the MMC Association has introduced a memory card that can work at low voltage and is compatible with the original RS-MMC--MMC moboile, which can be used at 1.65 to 1.95V and 2.7 to 3.6V. Working in a mode, the theoretical transmission speed can reach up to 52MB/s. It is called dual voltage RS-MMC. The size of the MMC moboile and the RS-MMC card are exactly the same. The biggest difference is that the MMC moboile has 13 gold fingers.
Compared to the microSD card, the MMC micro is slightly larger, 12mm x 14mm x 1.1mm. Like the MMC moboile, it supports dual voltage and is suitable for mobile phones and other handheld portable devices that require high size and battery life.
Understand that this card is a security card, it is better than the CF card and the early SM card in terms of security performance. It is a brand new memory card product jointly developed by Matsushita, Toshiba and SanDisk of Japan. The biggest feature is to ensure the security and confidentiality of data through encryption. The SD card can be seen as an upgrade of the MMC in many ways. Both form and work the same way, except that the MMC card is slightly thinner, but MMC cards can be used with machines that use SD card devices. Its external dimensions are 32mm × 24mm × 2.1mm.
The SD card is slightly bloated for small digital products such as mobile phones. At the same time, in order to catch up with Duo and Xd, the SD card camp has released a smaller memory card called "miniSD". Its external dimensions are 20mm × 21.5mm × 1.4mm, the package area is 44% of the original SD card, the volume is 63% of the original SD card, with 11 gold fingers (only 9 SD cards). It can also be used as an SD card with a riser card. The card is widely used on mobile phones such as Dopod and Panasonic.
The microSD card standard was developed by the SD Association in 2005 with reference to the T-Flash standard. The T-Flash card and the microSD card are compatible. Compared with the miniSD card, the microSD card is smaller in size, 11mm × 15mm × 1.4mm, which is only about a quarter of the standard SD card. It is the smallest memory card on the market.
SD card data recovery SD card data recovery skills Memory card common fault analysis and solution
1. Fault phenomenon: When the SD card is inserted into the computer through the card reader, the computer displays “Do you want to format it”, insert the SD card into the camera, and “SD card error” appears, and the photo inside the card cannot be seen.
2. Troubleshooting: When the multi-purpose card reader is used to access the computer, the drive letter of the SD card appears. After double-clicking, the prompt “Do you want to format” appears. Because the multi-purpose card reader is normal, the estimated reason is: SD card has a problem, the SD card has a virus, and the SD card file is deconstructed and damaged. Since the data in the SD card cannot be read, the format processing is used. After the operation is completed, double-click to open the drive letter of the SD card, and there is no data on the card. Then, use the file recovery software (Recover My Files) to completely format and recover the SD card, copy the recovered files to the SD card, insert the SD card into the digital camera and test the operation normally, and the data recovery is completed.
3, failure analysis: virus detection of the recovered SD card, not found, to rule out virus damage. Then test on the computer, found that the SD card's drive letter appears, double-click the drive letter, and then the "Do you want to format" prompt, view the properties, the card capacity increased to 544GB, and the actual capacity is 2GB, format operation The operation could not be completed. Re-switch the SD card to the multi-card reader and find that the recovered data is completely correct. ........ Prove that there is a problem with the card reader of the large-capacity display. .......
4, the last tip:
(1) When using a mobile storage device to operate on a computer, the plugging and unplugging device should be carried out according to the program, so don't be bothered.
(2) When using mobile storage devices and card readers, you should use genuine products with company logos, especially to avoid using simple (10 yuan) card readers.
(3) Where the drive letter can appear, the data cannot be opened, the garbled characters appear, and the capacity of the disk is 0 bytes, the file recovery software is first used to restore the data and then repaired.
(4) When the mobile storage device fails to detect the drive letter, whether it is formatted, cannot be formatted, cannot be copied, I/O error, red light has been flashing rapidly, etc., use the UNSD tool for disk repair, if not If you are successful, contact a professional repair or dealer to return the product.
Use of SD card
SD cards are used in the following portable digital devices:
● Digital camera to store photos and videos
●Digital camcorder to store photos and videos
● Personal digital assistant (PDA) stores various types of data
●Mobile phone to store photos, ring tones, music, short films, etc.
SD cards are mostly used in MP3 players, digital video cameras, digital cameras, etc., and are also used in laptops. The projected area is the same as the MMC card, but it is slightly thicker, 2.1mm, but the capacity of the SD card is much larger, and the read/write speed is also 4 times faster than the MMC card. At the same time, the interface of the SD card is compatible with the MMC card, and the interface supporting the SD card mostly supports the MMC card. At present, SD cards are rapidly spreading in digital cameras, and they have become mainstream. The SD card has developed rapidly this year and has begun to threaten the market share of CF cards. This is because the size of the SD card is much smaller than that of the CF card, and the gap between the SD card in terms of capacity, performance and price is getting smaller and smaller, and the mobile phone supporting the SD card in the past two years is rapidly gaining momentum in the market. The rapid growth of SD cards is definitely not accidental. The most important point is that the MMC card can also be compatible with the SD card, which is one of the reasons why the SD card quickly became popular. Note, however, that on some products, such as mobile phones, SD cards and MMS cards are not compatible. The current SD card capacity ranges from 8MB to 32GB.