Tashkent university of information technologies subject of operating systems

1. General view
SD memory cards are a new generation of high-speed storage devices based on semiconductor fast flash memory. SD memory card technology is derived from the MULTIMEDIA Card format, which developed an SDIO (SD Input / Output) card based on a compatible SD memory card. This compatibility includes mechanical, electronic, electrical, alarm, and software. SD cards and SDIO cards are commonly referred to as SD memory cards.
The SD card has high memory capacity, fast data transfer speed, excellent mobile flexibility and good security, they are widely used in portable devices such as digital cameras, tablets and multimedia players.
The SD card structure ensures the security of digital files and it is also easy to reformat, so there is a wide range of applications. Multimedia files such as music, movies can be easily saved to the SD card. There are many brands of SD cards in the market such as SanDisk, Kingmax, Panasonic and Kingston.
SD card is a new type of memory device with the following features:
● High memory capacity, the most common sizes: 8GB, 16GB, 32GB, 128GB, 256GB, etc.
● The built-in encryption technology adapts to the copyright protection function based on the SDMI protocol.
● High speed data transmission; maximum read and write speed is 100 Mb / s.
● Lightweight, easy to carry, strong impact resistance.
SD card features
The digital copyright protection scheme included in the SD card is set in accordance with the Record Media Content Protection (CPRM) proposed in 4C. Its main part is the use of the Cryptomeria password (also known as “C2”). This feature is hidden. The DVD-AUDIO CD also uses an encryption scheme very similar to CPPM. SD card (Secure Digital Memory Card) is a new generation of memory devices based on semiconductor flash memory. The SD card was co-developed in June 1999 by Panasonic, Toshiba and SanDisk at Toshiba and SanDisk. The size is similar to the SD memory card of the stamp, only 2 grams, but with high memory capacity, fast data transfer speed, excellent mobile flexibility. , and good security.
The SD card combines SanDisk flash memory card management and MLC (Multilevel Cell) technology and Toshiba 0.16U and 0.13U NAND technology. It is connected to a dedicated drive via a 9-pin interface and does not require an additional power supply to remember the data on it. In addition, it is an integrated rigid engine and has no moving part, so there is no need to worry about damaging the mechanical movement.
The biggest feature of SD cards is to ensure the confidentiality of data through encryption. The SD card is compatible with the MultiMedia card in the form and conforms to the MMC card interface specification. However, some products such as mobile phones, SD cards and MMS cards may not be compatible. SD card sales are higher than the equivalent MultiMedia Card.
The SD card is used for MP3 Walkman, digital camera, digital camera and so on. Its projection area is the same as an MMC card, but the capacity of the SD card is much larger, and the read and write speeds are also 4 times faster. MMC card. However, the SD card interface is compatible with the MMC card, supporting the SD card interface to support the MMC card. In 2013, the SD card quickly became popular in digital cameras, and it became the mainstream. The SD card grew rapidly in 2013 and began to threaten the market share of the CF card. This is because the size of the SD card is much smaller than the CF card and the SD card is smaller and smaller in terms of size, performance and price and the gap between the CF card. The rapid growth of the SD card is certainly not accidental.