Secure Digital card
Pair of SD cards
Media type	Memory Card
Capacity	Standard SD: 8 MB to 2 GB SDHC: 4 GB to 32 GB (theoretical max for SDHC is 2 TB.)
Developed by	SD Card Association
Usage	Portable devices, including digital cameras and handheld computers
Extended from	MultiMediaCard (MMC)

Secure Digital (SD) is a flash (non-volatile) memory card format developed by Matsushita, SanDisk, and Toshiba for use in portable devices. Today it is widely used in digital cameras, handheld computers, PDAs, mobile phones, GPS receivers, and video game consoles. SD card capacities range from 8 MB to 2 GB and from 4 GB to 32 GB for SDHC cards as of 2008. Image File history File links Metadata Size of this preview: 800 × 561 pixelsFull resolution (946 × 663 pixel, file size: 150 KB, MIME type: image/jpeg) Two SD Cards, Left: 2 Gigabyte SD (Secure Digital) Memory Card, Model Number SD-M02G, Manufactured in Japan by Toshiba; Right: 1 Gigabyte SD (Secure... Four major types of memory cards (from left to right: CompactFlash, Memory Stick, Secure Digital, and xD. A memory card or flash memory card is a solid-state electronic flash memory data storage device used with digital cameras, handheld and Mobile computers, telephones, music players, video game consoles, and other... The SD Card Association markets and promulgates technical standards for SD Card technology: Secure Digital card and miniSD Card. ... A 32 MB MultiMediaCard MultiMediaCard A 128 MB RS-MMC card and an adapter An RS-MMC card with adapter attached The MultiMediaCard (MMC) is a flash memory memory card standard. ... A USB flash drive. ... Non-volatile memory, nonvolatile memory, NVM or non-volatile storage, is computer memory that can retain the stored information even when not powered. ... Four major types of memory cards (from left to right: CompactFlash, Memory Stick, Secure Digital, and xD. A memory card or flash memory card is a solid-state electronic flash memory data storage device used with digital cameras, handheld and Mobile computers, telephones, music players, video game consoles, and other... Matsushita Electric Industrial Co. ... SanDisk Corporation (NASDAQ: SNDK), formerly SunDisk, is an American multinational corporation which designs and markets flash memory card products. ... Toshiba Corporations headquarters (Center) in Hamamatsucho, Tokyo Toshiba Corporation sales by division for year ending March 31, 2005 Toshiba Corporation ) (TYO: 6502 ) is a Japanese multinational conglomerate manufacturing company, headquartered in Tokyo, Japan. ... Digital cameras are a remarkable advance in technology. ... A mobile device (also known as converged device, handheld device, handheld computer, Palmtop or simply handheld) is a pocket-sized computing device, typically comprising a small visual display screen for user output and a miniature keyboard or touch screen for user input. ... User with Treo (PDA with smartphone functionality) Personal digital assistants (PDAs) are handheld computers, but have become much more versatile over the years. ... Over fifty GPS satellites such as this NAVSTAR have been launched since 1978. ... Game console redirects here. ... This article is about a unit of data. ... This article is about the unit of measurement. ... 2008 (MMVIII) is the current year, a leap year that started on Tuesday of the Anno Domini (or common era), in accordance with the Gregorian calendar. ...

The format has proven to be very popular. However, a change in the format, while allowing capacities greater than 2 GB (SDHC), has created compatibility issues with older devices which cannot read the new format. Since SDHC format cards have the same physical shape and form factor as the older format, this has caused considerable confusion for consumers.^[1][2] SDHC cards require an SDHC capable device firmware, generally not found with older devices. Secure Digital (SD) is a flash (non-volatile) memory card format developed by Matsushita, SanDisk, and Toshiba for use in portable devices. ... A microcontroller, like this PIC18F8720 is controlled by firmware stored inside on FLASH memory In computing, firmware is a computer program that is embedded in a hardware device, for example a microcontroller. ...

History

In August of 1999, Matsushita (better known by its Panasonic brand name), SanDisk, and Toshiba first announced an agreement on a comprehensive collaboration to jointly develop, specify and widely promote a next generation secure memory card called the SD Memory Card. With a physical profile of 24 mm × 32 mm × 2.1 mm, the new card provided both an SDMI-compliant (Secure Digital Music Initiative), high-level of copyright protection and high-density memory capacity for the time. The new memory card format was designed to compete with Sony's Memory Stick format that was released in 1998. Events of 2008: (EMILY) Me Lesley and MIley are going to China! This article is about the year. ... Matsushita Electric Industrial Co. ... Panasonic (パナソニック Panasonikku) is an international brand name for Japanese electric products manufacturer Matsushita Electric Industrial Co. ... SanDisk Corporation (NASDAQ: SNDK), formerly SunDisk, is an American multinational corporation which designs and markets flash memory card products. ... Toshiba Corporations headquarters (Center) in Hamamatsucho, Tokyo Toshiba Corporation sales by division for year ending March 31, 2005 Toshiba Corporation ) (TYO: 6502 ) is a Japanese multinational conglomerate manufacturing company, headquartered in Tokyo, Japan. ... SDMI (Secure Digital Music Initiative) was a forum formed in late 1998, comprised of more than 200 IT, consumer electronics, security technology, ISP and recording industry companies with the purpose of developing technology specifications that protect the playing, storing and distributing of digital music. ... Sony Corporation ) is a Japanese multinational corporation and one of the worlds largest media conglomerates with revenue of $66. ... This article is about Sonys proprietary memory format. ... Year 1998 (MCMXCVIII) was a common year starting on Thursday (link will display full 1998 Gregorian calendar). ...

The “Secure” in Secure Digital comes from the card’s origin. To create the SD card, Toshiba added encryption hardware to the already-existent MMC, to calm music industry concerns that MMCs would allow for easy piracy of music. (A similar scheme is the MagicGate standard used in Memory Sticks.) In theory, the encryption would allow some enforcement of Digital rights management[1] schemes on digital music, but the capability is rarely used. A 32 MB Multi Media Card Multi Media Card A 128 MB RS-MMC card and an adapter The Multi Media Card (MMC) is a flash memory memory card standard. ... A memory stick with MagicGate technology. ... This article is about Sonys proprietary memory format. ... Digital rights management (DRM) is an umbrella term that refers to access control technologies used by publishers and copyright holders to limit usage of digital media or devices. ...

The signature “SD” logo was actually developed for another use entirely: it was originally used for “Super Density Disc”, a prototype format by Toshiba created during the development of DVD. This is why the “D” looks similar to half of an optical disc, possibly reinforced by the SD card's music industry features and consumers' familiarity with music on optical discs. Toshiba Corporations headquarters (Center) in Hamamatsucho, Tokyo Toshiba Corporation sales by division for year ending March 31, 2005 Toshiba Corporation ) (TYO: 6502 ) is a Japanese multinational conglomerate manufacturing company, headquartered in Tokyo, Japan. ... DVD (also known as Digital Versatile Disc or Digital Video Disc - see Etymology) is a popular optical disc storage media format. ... CDDA logo/trademark Red Book is the standard for audio CDs (Compact Disc Digital Audio system, or CDDA). ...

At the 2000 CES trade show Matsushita, SanDisk and Toshiba Corporation announced that a new industry-wide association would be created to set industry standards for their proprietary SD (Secure Digital) Memory Card and promote its wide acceptance in digital applications. The new organization, named the SDAssociation (SDA), is headquartered in California and its executive membership includes some 30 world-leading high-tech companies and major content companies. Sampling of the SD Memory Card began in the first quarter of 2000, and production shipments commenced in the second quarter of 2000. The card was initially available in 32 and 64 megabyte capacities. The International Consumer Electronics Show (CES) is a trade show held each January in Las Vegas, Nevada, and is sponsored by the Consumer Electronics Association. ... The SD Card Association markets and promulgates technical standards for SD Card technology: Secure Digital card and miniSD Card. ... This article is about a unit of data. ...

In April 2006, the SDA released a detailed specification for the non-security related portions of the SD Memory Card standard. In addition, they released specifications for the SDIO cards and the standard SD host controller. During the same year, specifications were finalised for the small form-factor microSD (formerly known as TransFlash) and SDHC, with capacities in excess of 2 GB and a minimum sustained read/write speed of 2.2 MB/s. A microSD card (right) next to its SD adapter (left) Dissected 64 MB microSD Card, showing cross section through memory chips and printed circuit board microSD is a format for removable flash memory cards. ...

Design and Implementation

An SD card, mini SD card, and micro SD card from top to bottom.

SD cards are based on the older MultiMediaCard (MMC) format, but have a number of differences: A 32 MB MultiMediaCard MultiMediaCard A 128 MB RS-MMC card and an adapter An RS-MMC card with adapter attached The MultiMediaCard (MMC) is a flash memory memory card standard. ...

• The SD card is asymmetrically shaped in order not to be inserted upside down, while an MMC would go in most of the way but not make contact if inverted.
• Most SD cards are physically thicker than MMCs. SD cards generally measure 32 mm × 24 mm × 2.1 mm, but can be as thin as 1.4 mm, just like MMCs (see below).
• The contacts are recessed beneath the surface of the card (like Memory Stick cards), protecting the contacts from contact with the fingers.
• SD cards typically have transfer rates in the range of 10-20 MBytes/s, but this is always changing, particularly in light of recent improvements to the MMC standard. ^[3]

Devices with SD slots can use the thinner MMCs, but the standard SD cards will not fit into the thinner MMC slots. miniSD and microSD cards can be used directly in SD slots with a simple passive adapter, since they differ in size and shape but not electrical interface. With an active electronic adapter, SD cards can be used in CompactFlash or PC card slots. Some SD cards include a USB connector for compatibility with desktop and laptop computers, and card readers allow SD cards to be accessed via connectivity ports such as USB, FireWire, and the parallel printer port. SD cards can also be accessed via a floppy disk drive with a FlashPath adapter. This article is about Sonys proprietary memory format. ... MMC may stand for: In computing and electronics: MultiMediaCard, a solid state disk or flash memory data storage device Microsoft Management Console, a framework for system administration tools in modern Microsoft Windows operating systems Multi-Memory Controller, a special microchip in Nintendo Entertainment System Game Paks MIDI Machine Control, part... The miniSD Card is a small form factor removable and portable memory device intended for use in cell phones/mobile phones, digital cameras, MP3 players and many other gadgets. ... A microSD card (right) next to its SD adapter (left) Dissected 64 MB microSD Card, showing cross section through memory chips and printed circuit board microSD is a format for removable flash memory cards. ... A 32 MB High Speed CompactFlash Type I card CompactFlash (CF) was originally developed as a type of data storage device used in portable electronic devices. ... The PCMCIA is the Personal Computer Memory Card International Association, an industry trade association that creates standards for notebook computer peripheral devices. ... A card reader is a device used for communication with a smart card or a flash memory card. ... Note: USB may also mean upper sideband in radio. ... The 6-pin and 4-pin FireWire 400 Connectors The alternative ethernet-style cabling used by 1394c FireWire is Apple Inc. ... This article is about the Centronics style port. ... A floppy disk is a data storage device that is composed of a disk of thin, flexible (floppy) magnetic storage medium encased in a square or rectangular plastic shell. ... FlashPath (FlashPath Floppy Disk Adapter) is a name for a series of devices produced by SmartDisk that allow a variety of memory cards to be used in a 3. ...

Optional write-protect tab

When looking at the card from the top (see pictures) there is one required notch on the right side (the side with the diagonal notched corner).

On the left side there is usually a slidable tab. This is the write-protect tab. The MMC has neither notch. It is easy to mistake this tab as an electronic on/off switch built inside the card, but it is used simply as a tab/notch switch. The tab/notch works the same way as the notches on compact audio cassettes and videotape cassette tapes or floppy disks, where the device senses the tab/notch and determines if the card is write-protected or not. Write protection, (also known as record protection) is a mechanism that prevents erasure of valuable data by the accidental recording or storing of new data. ... Typical 60-minute Compact Cassette. ... Bottom view of VHS videotape cassette with magnetic tape exposed Videotape is a means of recording images and sound onto magnetic tape as opposed to movie film. ... Compact audio cassette Magnetic tape is a non-volatile storage medium consisting of a magnetic coating on a thin plastic strip. ... A floppy disk is a data storage device that is composed of a disk of thin, flexible (floppy) magnetic storage medium encased in a square or rectangular plastic shell. ...

When this write-protect tab is in the down position (away from the end that is inserted) then it is write protected and read-only. When the tab is in the up position it is write enabled. Since the tab is optional, the card can have no switch and no notch, which makes the card always writable, or it can have an empty notch and be a ROM card, which makes the card always write-protected and read-only. If the tab becomes broken or falls off then the card will become a write-protected ROM card and no longer be writable. A possible troubleshooting solution would be to apply tape over the notched area (avoiding the connectors and the other notch) to configure the card in a permanent writable state. Read-only memory (usually known by its acronym, ROM) is a class of storage media used in computers and other electronic devices. ...

If the sensor inside the device is faulty and unable to detect the tab/notch, all SD cards will seem to be either write-protected or write-enabled, depending on the failure mode.

The write protect tab feature is optional within the Secure Digital Association guidelines. Some manufacturers claim that the write switch is easily broken, and do not include it on all their card models. ^[4] For writable cards, this is simply a matter of changing the molding of the outer shell so that the notch doesn't exist.

Some music and film media companies (e.g. Disney) have released limited catalogs of records and/or videos on SD. These usually contain DRM-encoded Windows Media files, making use of the SD format's DRM capabilities. Such media is usually permanently marked read-only, by adding the notch with no tab. These cards could be further protected (and possibly produced more cheaply) by manufacturing the card with true ROM rather than flash memory; it is not clear if any vendors have taken this approach. Disney may refer to: The Walt Disney Company and its divisions, including Walt Disney Pictures. ... Digital rights management (DRM) is an umbrella term that refers to access control technologies used by publishers and copyright holders to limit usage of digital media or devices. ... Windows Media is a multimedia framework for media creation and distribution for Microsoft Windows. ... Read-only memory (usually known by its acronym, ROM) is a class of storage media used in computers and other electronic devices. ...

File system

Like other flash card technologies, most SD cards ship preformatted with the FAT or FAT 32 file system. The ubiquity of this file system allows the card to be accessed on virtually any host device with an SD reader. Also, standard FAT maintenance utilities (e.g. ScanDisk) can be used to repair or retrieve corrupted data. However, because the card appears as a removable hard drive to the host system, the card can be reformatted to any file system supported by the operating system. File Allocation Table (FAT) is a partially patented file system developed by Microsoft for MS-DOS and was the primary file system for consumer versions of Microsoft Windows up to and including Windows Me. ... File Allocation Table (FAT) is a partially patented file system developed by Microsoft for MS-DOS and was the primary file system for consumer versions of Microsoft Windows up to and including Windows Me. ... For library and office filing systems, see Library classification. ... This article does not cite any references or sources. ...

It is worth noting that while defragmentation utilities can be run against an SD card, there is no point in doing so. Defragmentation is a process intended to optimize access to data on a drive with spinning platters and moving heads; however, since flash memory is truly random-access (a read to an adjacent cell is no faster than a read from any other cell), there is no performance gain. Further, the flash controller abstracts the physical memory location used for a given "sector", so that the host machine doesn't really know the layout of the data. Finally, as the defragmentation process moves data around, attempting to optimize it, a small portion of the flash memory's wear life is consumed. In the context of administering computer systems, defragmentation is a process that reduces the amount of fragmentation in file systems. ...

However, note that any file recovery tool will struggle to recover files from highly fragmented data if the File Allocation Table becomes highly corrupted.

Speeds

There are different speed grades available which are measured with the same system as CD-ROMs, in multiples of 150 kB/s (1x = 150 kB/s). Basic cards transfer data up to six times (6x) the data rate of the standard CD-ROM speed (900 kB/s vs. 150 kB/s). High-speed cards are made with higher data transfer rates like 66x (10 MB/s), and high-end cards have speeds of 150x or higher. Note that maximum read speed and maximum write speed may be different, with maximum write speed typically lower than maximum read speed. Some digital cameras require high-speed cards (write speed) to record video smoothly or capture multiple still photographs in rapid succession. The SD card specification 1.01 allows for a maximum speed of 66x. Higher speeds of up to 150x are defined by specification 1.1. The CD-ROM (an abbreviation for Compact Disc Read-Only Memory (ROM)) is a non-volatile optical data storage medium using the same physical format as audio compact discs, readable by a computer with a CD-ROM drive. ... A kilobyte (derived from the SI prefix kilo-, meaning 1,000) is a unit of information or computer storage equal to either 1,000 bytes or 1,024 bytes (210), depending on context. ... This article is about a unit of data. ... Digital cameras are a remarkable advance in technology. ...

The following table lists some common ratings and their respective maximum transfer rates.

Openness of standards

The insides of a Samsung 512 MB SD Card. The top chip is the SD controller and the bottom one is the NAND flash chip that actually stores the data.

The insides of a SanDisk 128 MB SD Card.

Like most memory card formats, SD is covered by numerous patents (e.g. US patent 5602987) and trademarks. Image File history File links Metadata Size of this preview: 800 × 600 pixelsFull resolution‎ (2,048 × 1,536 pixels, file size: 1. ... Image File history File links Metadata Size of this preview: 800 × 600 pixelsFull resolution‎ (2,048 × 1,536 pixels, file size: 1. ... Controllers, when used in computing and especially in computer hardware, often occur when interfacing with peripherals. ... A USB Flash Memory Device Flash memory is a form of EEPROM (Electrically-Erasable Programmable Read-Only Memory) that allows multiple memory locations to be erased or written in one programming operation. ... For other uses, see Patent (disambiguation). ... “(TM)” redirects here. ...

There are three versions of the SD specification: 1.0, 1.1 and 2.0. These were originally only available after agreeing to a non-disclosure agreement (NDA) which prohibits the development of an open source driver, a fact that generates a fair amount of consternation in the open-source and free software communities. The system was eventually reverse-engineered though, and the non-DRMed sections of the memory cards could be accessed by free software drivers. A non-disclosure agreement (NDA), also called a confidential disclosure agreement (CDA), confidentiality agreement or secrecy agreement, is a legal contract between at least two parties which outlines confidential materials or knowledge the parties wish to share with one another for certain purposes, but wish to restrict from generalized use. ... Open source refers to projects that are open to the public and which draw on other projects that are freely available to the general public. ... Free software is software that can be used, studied, and modified without restriction, and which can be copied and redistributed in modified or unmodified form either without restriction, or with minimal restrictions only to ensure that further recipients can also do these things. ... Reverse engineering (RE) is the process of taking something (a device, an electrical component, a software program, etc. ...

These days however, the SD Card Association (SDA) has made access to a simplified version of the specification under a less-restrictive licence.^[5] Although most open-source drivers were written before this, it has helped them to solve some compatibility issues. The SD Card Association markets and promulgates technical standards for SD Card technology: Secure Digital card and miniSD Card. ...

In 2006, the SD Card Association also released a simplified version of their host controller interface specification (not to be confused with the physical specification, which covers the actual cards and their protocol).^[6] Like the physical specification, most of the information had already been discovered before the public release^[7] and at least Linux had a fully free driver for it. Still, building a chip conforming to this specification caused the One Laptop Per Child project to claim "the first truly Open Source SD implementation, with no need to obtain an SDI license or sign NDAs to create SD drivers or applications."^[8] This article is about operating systems that use the Linux kernel. ... OLPC redirects here. ...

For the most part, the lack of complete, open SD specifications mainly affects embedded systems, since desktop users generally read SD cards via USB-based card readers. These card readers present a standard USB mass storage interface to memory cards, thus separating the operating system from the details of the underlying SD interface. However, embedded systems (such as portable music players) usually access SD cards directly, and therefore complete programming information is necessary. Desktop card readers are themselves examples of such embedded systems; the manufacturers of these readers have usually paid the SDCA for complete access to the SD specifications. Many notebook computers now include SD card readers not based on USB; device drivers for these essentially access the SD card directly, as in embedded systems. A router, an example of an embedded system. ... Note: USB may also mean upper sideband in radio. ... A card reader is a device used for communication with a smart card or a flash memory card. ... A keydrive, a typical USB mass storage device The USB mass storage device class is a set of computing communications protocols defined by the USB Implementers Forum that run on the Universal Serial Bus. ...

Technical explanation

SD supports at least three transfer modes:

• One-bit SD mode (separate command and data channels and a proprietary transfer format)
• Four-bit SD mode (uses extra pins plus some reassigned pins)
• SPI mode (basically, a simpler subset of the SD protocol for use with microcontrollers)

All memory cards must support all three modes, except for microSD where SPI is optional. The cards must also support clock frequencies of up to 25 MHz for regular cards, and 50 MHz for high-speed cards. A microcontroller is a computer-on-a-chip optimised to control devices. ...

Royalties for SD/SDIO licenses are imposed for manufacture and sale of memory cards and host adapters (1000 USD per year plus membership at 1500 USD/year) but SDIO cards can be made without royalties and MMC host adapters do not require a royalty. MMCs have a seven-pin interface; SD and SDIO have expanded this to nine pins and MMC Plus expands this even further with thirteen pins.

DRM features

The digital rights management scheme embedded in the SD cards is defined as the Content Protection for Recordable Media (CPRM) by the 4C Entity and is centered around use of the Cryptomeria cipher (also known as C2). The specification is kept secret and is only accessible to licensees. DVD-Audio uses a very similar scheme known as Content Protection for Prerecorded Media (CPPM). This type of DRM is associated with SDMI, an organisation set up by the RIAA to promote such hardware-based copy protection schemes. Many SD cards are marked on the packaging as being 'SDMI Compliant' for this reason. This DRM has not been seen "in the wild" and few, if any, devices appear to provide support for it. Digital rights management (DRM) is an umbrella term that refers to access control technologies used by publishers and copyright holders to limit usage of digital media or devices. ... CPRM or Content Protection for Recordable Media is a mechanism for controlling the copying, moving and deletion of digital media on a host device, such as a personal computer, or other digital player. ... The 4C Entity (which should be read out as the four company entity) is a consortium formed by IBM, Intel, Matsushita and Toshiba to establish a common platform for digital rights management schemes. ... The Cryptomeria cipher, commonly refered to as C2 is a proprietary block cipher defined and licensed by the 4C Entity. ... DVD-Audio is a digital format for delivering very high-fidelity audio content on a DVD. DVD-Audio includes no video and should not be confused with video DVDs containing concerts and music videos. ... SDMI (Secure Digital Music Initiative) was a forum formed in late 1998, comprised of more than 200 IT, consumer electronics, security technology, ISP and recording industry companies with the purpose of developing technology specifications that protect the playing, storing and distributing of digital music. ... The RIAA Logo. ...

Super*Talent, a manufacturer of computer memory, has created the "Super Digital" card. They are the same in appearance and function to regular Secure Digital cards, but they lack the CPRM code commonly found in Secure Digital cards. ^[9]

Compared to other flash memory formats

Overall, SD is less open than CompactFlash or USB flash memory drives, which can be implemented for free but require licensing fees for the associated logos and trademarks. A 32 MB High Speed CompactFlash Type I card CompactFlash (CF) was originally developed as a type of data storage device used in portable electronic devices. ... JumpDrive redirects here. ...

However, SD is much more open than Memory Stick, for which no public documentation nor any documented legacy implementation is available. All SD cards can, at least, be accessed freely using the well-documented SPI/MMC mode. This article is about Sonys proprietary memory format. ...

xD cards are simply 18-pin NAND flash chips in a special package, and support the standard command set for raw NAND flash access (more information). Although the raw hardware interface to xD cards is well-understood, the layout of its memory contents--necessary for interoperability with xD card readers and digital cameras--is totally undocumented. The consortium that licenses xD cards has not released any publicly available technical information. The xD-Picture Card is a type of flash memory card, used mainly in digital cameras. ... A USB Flash Memory Device Flash memory is a form of EEPROM (Electrically-Erasable Programmable Read-Only Memory) that allows multiple memory locations to be erased or written in one programming operation. ... The xD-Picture Card is a type of flash memory card, used mainly in digital cameras. ...

Different types of MMC/SD cards

The SD card is not the only flash memory card standard ratified by the Secure Digital Card Association. Other SD Card Association formats include miniSD, microSD (formerly known as TransFlash before ratification by the SD Card Association), and SDHC (Secure Digital High Capacity, for capacities above 4 GB). SDHC is not fully compatible with the format that it extends, in that SD devices that do not specifically support SDHC will not work with the newer cards. Four major types of memory cards (from left to right: CompactFlash, Memory Stick, Secure Digital, and xD. A memory card or flash memory card is a solid-state electronic flash memory data storage device used with digital cameras, handheld and Mobile computers, telephones, music players, video game consoles, and other... The miniSD Card is a small form factor removable and portable memory device intended for use in cell phones/mobile phones, digital cameras, MP3 players and many other gadgets. ... A microSD card (right) next to its SD adapter (left) Dissected 64 MB microSD Card, showing cross section through memory chips and printed circuit board microSD is a format for removable flash memory cards. ... A microSD card (right) next to its SD adapter (left) Dissected 64 MB microSD Card, showing cross section through memory chips and printed circuit board microSD is a format for removable flash memory cards. ...

These smaller miniSD and microSD cards are usable in full size MMC/SD/SDIO slots with an adapter (which must route the electrical connections as well as making physical contact). It should be noted, however, that it is already difficult to create I/O devices in the SD form factor and this will be even more difficult in the smaller sizes. However, a WiFi card for mini-SDIO is already available from Spectec.

As SD slots still support MMCs, the separately-evolved smaller MMC variants are also compatible with SD-supporting devices. Unlike miniSD and microSD (which are sufficiently different from SD to make mechanical adapters necessary), RS-MMC slots maintain backward compatibility with full-sized MMCs, because the RS-MMCs are simply shorter MMCs. More information on these variants can be found in the article about the MultiMediaCard standard. The miniSD Card is a small form factor removable and portable memory device intended for use in cell phones/mobile phones, digital cameras, MP3 players and many other gadgets. ... A microSD card (right) next to its SD adapter (left) Dissected 64 MB microSD Card, showing cross section through memory chips and printed circuit board microSD is a format for removable flash memory cards. ... A 32 MB MultiMediaCard MultiMediaCard A 128 MB RS-MMC card and an adapter An RS-MMC card with adapter attached The MultiMediaCard (MMC) is a flash memory memory card standard. ...

It is also important to note, that unlike for data storage (which typically works everywhere where an SD slot is present), an SDIO device must be supported and equipped with drivers and applications for the host system and usually doesn't work outside of the manufacturer's scope (which means, for example, that an HP SDIO camera usually does not work with PDAs for which it is not listed as an accessory). This behavior is often not expected by end users (who expect that only the SD slot is required) and is similar to compatibility problems among Bluetooth devices. Bluetooth logo This article is about the electronic protocol named after Harald Bluetooth Gormson. ...

Most, possibly all, current MMC flash memory cards support SPI mode even if not officially required as failure to do so would severely affect compatibility. All cards currently made by SanDisk, Ritek/Ridata, and Kingmax digital appear to support SPI. Also, MMCs may be electrically identical to SD cards but in a thinner package and with a fuse blown to disable SD functionality (so no SD royalties need to be paid). Some MicroSD cards do not support SPI mode.

MMC defined the SPI and one-bit MMC/SD protocols. The underlying SPI protocol has existed for years as a standard feature on many microcontrollers. From a societal perspective, the justification for a new incompatible SD/MMC protocol is questionable; the development of a new incompatible and unnecessary protocol may help trade associations collect licensing and membership fees but it raises the cost of hardware and software in many ways. The new protocol used open collector signalling to allow multiple cards on the same bus but this actually causes problems at higher clock rate. While SPI used three shared lines plus a separate chip select to each card, the new protocol allows up to 30 cards to be connected to the same three wires (with no chip select) at the expense of a much more complicated card initialization and the requirement that each card have a unique serial number for plug and play operation; this feature is rarely used and its use is actively discouraged in new standards (which recommend a completely separate channel to each card) because of speed and power consumption issues. The quasi-proprietary one-bit protocol was extended to support four bit wide (SD and MMC) and eight bit (MMC only) transfers for more speed while much of the rest of the computer industry is moving to higher speed narrower channels; standard SPI could simply have been clocked at higher data rates (such as 133 MHz) for higher performance than offered by four-bit SD — embedded CPUs that did not already have higher clock rates available would not have been fast enough to handle the higher data rates anyway. The SD card association dropped support for some of the old one-bit MMC protocol commands and added support for additional commands related to copy protection. This page is a candidate for speedy deletion, because: Non-informative cut-paste If you disagree with its speedy deletion, please explain why on its talk page or at Wikipedia:Speedy deletions. ...

Compatibility issues with 2 GB and larger cards

Devices that use SD cards identify the card by requesting a 128-bit identification string from the card. For standard-capacity SD cards, 12 of the bits are used to identify the number of memory clusters (ranging from 1 to 4096) and 3 of the bits are used to identify the number of blocks per cluster (which decode to 4, 8, 16, 32, 64, 128, 256 or 512 blocks per cluster).

For the older 1.x implementations for standard capacity, a block was exactly 512 bytes. This gives 4096 x 512 x 512 = 1 gigabyte of memory. A later revision of the 1.x standard allowed a 4-bit field to indicate blocks of 1024 bytes instead, yielding 2-gigabyte memory cards. Devices designed before this change will incorrectly identify a 2-GB card as 1 GB. Some set the block size to 2048 to create an apparent 4-GB card. Others will either fail or incorrectly identify the card as a 1-GB card.

For the new SDHC high capacity card (2.0) implementation, 22 bits of the identification string are used to indicate the memory size in increments of 512 KBytes. Currently 16 of the 22 bits are allowed to be used, giving a maximum size of 32 GB. All SDHC 4-GB and larger cards must be 2.0 implementations. Two bits that were previously reserved and fixed at 0 are now used for identifying the type of card, 0=standard, 1=HC, 2=reserved, 3=reserved. Non-HC devices are not programmed to read this code and therefore cannot correctly read the identification of the card.

All SDHC readers work with standard SD cards.^[10]

Many older devices will not accept the 2 GB size even though it is in the revised standard. The following statement is from the SD association specification:

"To make 2 GByte card, the Maximum Block Length (READ_BL_LEN=WRITE_BL_LEN) shall be set to 1024 bytes. However, the Block Length, set by CMD16, shall be up to 512 bytes to keep consistency with 512 bytes Maximum Block Length cards (Less than and equal 2 Gbyte cards)."^[11]

Why v1.01 SD cards can have 4 GB capacity

In the SD Card Associations "Simplified Physical Layer Specification v2.00" it is specified in: The SD Card Association markets and promulgates technical standards for SD Card technology: Secure Digital card and miniSD Card. ...

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Table 5.3.2 CSD Register (CSD Version 1.0)

Name	Width	Cell type	CSD-slice
READ_BL_LEN	4	R	[83:80]
C_SIZE	12	R	[73:62]
C_SIZE_MULT	3	R	[49:47]

Page 91

READ_BL_LEN	Block-length
0-8	reserved
9	29 = 512 Bytes
10	210 = 1024 Bytes
11	211 = 2048 Bytes
12-15	reserved

"The maximum block length might therefore be in the range 512...2048 bytes"

Page 92

memory capacity = (C_SIZE+1) x 2^{(C_SIZE_MULT+2)} x 2^{(READ_BL_LEN)}

C_SIZE is 12 bits => 0..4095

C_SIZE_MULT is 3 bits => 0..7

Thus maximum capacity could be :

memory capacity = (4095+1) * 2⁽⁷⁺²⁾ * 2⁽¹¹⁾ = 4294967296 = 4 GiB

A gibibyte is a unit of information or computer storage. ...

Why v2.0 SDHC cards can have 2048 GB capacity

In the SD Card Associations "Simplified Physical Layer Specification v2.00": The SD Card Association markets and promulgates technical standards for SD Card technology: Secure Digital card and miniSD Card. ...

Page 97:

5.3.3 CSD Register (CSD Version 2.0)

"device size, C_SIZE, 22 bits, value 00 xxxxh, Readonly, CSD-slice [69:48]"

C_SIZE_MULT is removed.

Page 98:

"READ_BL_LEN This field is fixed to 9h, which indicates READ_BL_LEN=512 Byte."

Page 98:

"C_SIZE This field is expanded to 22 bits and can indicate up to 2 TBytes (It is the same as the maximum memory space specified by a 32-bit block address.) This parameter is used to calculate the user data area capacity in the SD memory card (not include the protected area). The user data area capacity is calculated from C_SIZE as follows: memory capacity = (C_SIZE+1) * 512K byte As the maximum capacity of the Physical Layer Specification Version 2.00 is 32 GB, the upper 6 bits of this field shall be set to 0."

Thus:

Memory capacity = (C_SIZE+1) * 512 K = (2²²-1+1) * 512 K = (4194304-1+1) * 512K = 2147483648 K = 2048 GB

Although the SD Card association have placed a limit in the 2.0 standard to a maximum of 32 GByte, the card data structures have bit fields to represent up to, and including, 2 TByte. Thus, the possibility exists for a manufacturer to violate the formal standard and produce larger SDHC cards, even though such cards would not have guaranteed compatibility with all SDHC readers.

SDHC

8GB SDHC cards

SDHC (Secure Digital High Capacity, SD 2.0) is an extension of the SD standard that appeared in June 2006.^[12] SDHC allows standard-compliant capacities in excess of 2 GB. SDHC cards are often formatted with the FAT32 file system, which supports partition sizes greater than 4 GB. ^[13] It uses the same form factor as SD, but the SD 2.0 standard in SDHC uses a different memory addressing method (sector addressing vs byte addressing), thus theoretically reaching a maximum capacity of up to 2048 GB. However the SD Card association have artificially defined the maximum limit of SDHC capacity to 32 GB. SDHC cards only work in SDHC compatible devices, but standard SD cards work in both SD and SDHC devices. The SDHC trademark is licensed to ensure compatibility. ^[14] Image File history File links Size of this preview: 800 × 501 pixelsFull resolution‎ (2,209 × 1,384 pixels, file size: 854 KB, MIME type: image/jpeg) File historyClick on a date/time to view the file as it appeared at that time. ... Image File history File links Size of this preview: 800 × 501 pixelsFull resolution‎ (2,209 × 1,384 pixels, file size: 854 KB, MIME type: image/jpeg) File historyClick on a date/time to view the file as it appeared at that time. ... File Allocation Table (FAT) is a partially patented file system developed by Microsoft for MS-DOS and was the primary file system for consumer versions of Microsoft Windows up to and including Windows Me. ... For library and office filing systems, see Library classification. ...

SDHC cards have SD Speed Class Ratings defined by the SD Association. The SD Speed Class Ratings specify the following minimum write speeds based on "the best fragmented state where no memory unit is occupied":^[15]

• Class 2: 2 MB/s
• Class 4: 4 MB/s
• Class 6: 6 MB/s

SDHC cards will often also advertise a maximum speed (such as 133x or 150x) in addition to this minimum Speed Class Rating. See section Speeds above for a further explanation.

SD and SDHC compatibility issues

As of early 2007, the simultaneous availability of non-standard 4 GB SD and of standards-compliant 4 GB SDHC cards, and incompatibilities between SD and SDHC have caused confusion among consumers buying memory devices.

SD and SDHC cards and devices have these compatibility issues :

• Devices that do not specifically support SDHC do not recognize SDHC memory cards.
• Some manufacturers have produced 4 GB SD cards that conform to neither the SD2.0/SDHC spec nor existing SD devices. ^[16]
• File System: SD cards are typically formatted with the FAT16 file system, while SDHC cards are typically formatted as FAT32. ^[17] However, both types of cards can support other general-purpose filesystems, such as UFS2/ext2 for example.

The UNIX file system (UFS) is a file system used by many Unix and Unix-like operating systems. ... The ext2 or second extended file system is a file system for the Linux kernel. ...

SDIO

A camera that uses the SDIO interface

SDIO stands for Secure Digital Input Output. Download high resolution version (1839x1641, 319 KB) Wikipedia does not have an article with this exact name. ... Download high resolution version (1839x1641, 319 KB) Wikipedia does not have an article with this exact name. ...

SD slots can actually be used for more than flash memory cards. Devices that support SDIO (typically PDAs like the Palm Treo, but occasionally laptops or cell phones) can use small devices designed for the SD form factor, like GPS receivers, Wi-Fi or Bluetooth adapters, modems, Ethernet adapters, barcode readers, IrDA adapters, FM radio tuners, TV tuners, RFID readers, digital cameras, or other mass storage media such as hard drives. “Treos” redirects here. ... Over fifty GPS satellites such as this NAVSTAR have been launched since 1978. ... Wi-Fi (IPA: ) is the common name for a popular wireless technology used in home networks, mobile phones, video games and more. ... Bluetooth logo This article is about the electronic protocol named after Harald Bluetooth Gormson. ... For other uses, see Modem (disambiguation). ... Ethernet is a large, diverse family of frame-based computer networking technologies that operate at many speeds for local area networks (LANs). ... A typical handheld barcode scanner A barcode reader (or barcode scanner) is an electronic device for reading printed barcodes. ... This article is about an Infrared communications protocol. ... FM radio is a broadcast technology invented by Edwin Howard Armstrong that uses frequency modulation to provide high-fidelity sound over broadcast radio. ... An EPC RFID tag used for Wal-Mart Radio Frequency Identification (RFID) is an automatic identification method, relying on storing and remotely retrieving data using devices called RFID tags or transponders. ... Look up digital camera in Wiktionary, the free dictionary. ...

A number of other devices have been proposed but not yet implemented, including RS-232 serial adapters, fingerprint scanners, SDIO to USB host/slave adapters (which would allow an SDIO-equipped handheld device to use USB peripherals and/or interface to PCs), magnetic strip readers, combination Bluetooth/Wi-Fi/GPS transceivers, cellular modems (PCS, CDPD, GSM, etc.), and APRS/TNC adapters. RS-232 (also referred to as EIA RS-232C or V.24) is a standard for serial binary data interchange between a DTE (Data terminal equipment) and a DCE (Data communication equipment). ... Bluetooth logo This article is about the electronic protocol named after Harald Bluetooth Gormson. ... Wi-Fi (IPA: ) is the common name for a popular wireless technology used in home networks, mobile phones, video games and more. ... Over fifty GPS satellites such as this NAVSTAR have been launched since 1978. ... Personal Communications Service or PCS is the name for the 1900-MHz radio band used for digital mobile phone services in Canada and the United States. ... Cellular Digital Packet Data (CDPD) uses unused bandwidth normally used by AMPS mobile phones between 800 and 900 MHz to transfer data. ... The Global System for Mobile communications (GSM: originally from Groupe Spécial Mobile) is the most popular standard for mobile phones in the world. ... Automatic Packet Reporting System (APRS) is an amateur radio based system for digital communications, most commonly used to automatically report the position (GPS coordinates) of a person or object, or weather data at a remote location. ... A TNC can refer to: A Threaded Neill-Concelman connector A transnational corporation A terminal node controller The Nature Conservancy The Noise Crew This is a disambiguation page — a list of articles associated with the same title. ...

SDIO cards are fully compatible with SD Memory Card host controller (including mechanical, electrical, power, signaling and software). When an SDIO card is inserted into a non SDIO-aware host, it will cause no physical damage or disruption to device or host controller. SPI bus topology is mandatory for SDIO, unlike SD Memory. Most of the SD Memory commands are not supported in SDIO. SDIO cards can contain 8 separate logical cards, though at the moment this is at most a memory and IO function. SD Slots will only take SD Cards. SDIO Slots will take SD Cards and SDIO cards. The Serial Peripheral Interface Bus or SPI (often pronounced es-pē-ī [IPA: ɛs pi aɪ] or spy [IPA: spaɪ]) bus is a synchronous serial data link standard named by Motorola that operates in full duplex mode. ...

SD cards with extra features

Various manufacturers have tried to make their SD cards stand out from the crowd in different ways

• SD Plus is a type of SD card made by Sandisk that has an integrated USB connector so it can be plugged directly into a USB port without needing any special card reader. ^[18] This concept has proven successful and other companies started introducing similar designs branded as duo SD.

• Capacity Display in 2006 A-DATA announced an SD card with its own digital display that would show how much free space is left on the card. ^[19]

• Eye-Fi, Inc. produces an SD card with Wi-Fi capability built in for 802.11g, 802.11b and backwards-compatible 802.11n wireless networks and supporting static WEP 40/104/128, WPA-PSK, WPA2-PSK security standards. The card works with any digital camera with an SD slot and can send captured images directly to a Windows PC or Apple computer wirelessly, where they can be automatically uploaded to web sites such as Flickr.com. When not in range of a wireless network connection, the card makes use of its 2GB capacity (EYE-FI-2GB model) until the images can be transferred. ^[20]

• Gruvi - A rare type of microSD card with extra DRM features

A-DATA Technology is a Taiwanese computer peripheral company. ... A microSD card (right) next to its SD adapter (left) Dissected 64 MB microSD Card, showing cross section through memory chips and printed circuit board microSD is a format for removable flash memory cards. ...

Market penetration

Secure Digital cards are used as storage media in these devices:

• Digital cameras for storing pictures
• Camcorders for storing still images and video clips
• PDAs for storing all kinds of data
• Mobile phones for storing images, sound clips and other media files - These devices tend to use smaller variants such as MicroSD and MiniSD
• Digital audio players
• Several game consoles:
  • Nintendo Wii console for storing multimedia and game save files.
  • Third-party homebrew devices for Nintendo DS for storing games, multimedia, and game save files.
  • Higher-end models of the Sony PlayStation 3 for storing multimedia and game save files.
  • GP2X GNU/Linux based portable games console.
  • Pandora (console) Upcoming GNU/Linux based portable games console using the OMAP platform.
• Digital audio broadcasting radios
• Global Positioning System receivers, for storing map and waypoint data, as well as digital photos and audio.
• Numerous digital picture frames
• PCs with built-in memory card readers. Such readers are usually connected internally via the USB bus.
• Many laptop computers come with an integrated SD card reader while some also read other types of cards.
• Amazon.com's Kindle handheld eBook reader to store additional files for reading.
• Panasonic plasma TVs have a built-in SD card reader to display images
• Many car stereo head units now include an SD slot for playing MP3, WMA, and other digital audio formats.
• Keychain-sized USB-based SD readers are available, allowing an SD (or in some cases miniSD or microSD) card to be used in the same manner as a USB flash drive.

Look up digital camera in Wiktionary, the free dictionary. ... Sony DV Handycam A camcorder is a portable electronic device for recording video images and audio onto an internal storage device. ... User with Treo (PDA with smartphone functionality) Personal digital assistants (PDAs) are handheld computers, but have become much more versatile over the years. ... A microSD card (right) next to its SD adapter (left) Dissected 64 MB microSD Card, showing cross section through memory chips and printed circuit board microSD is a format for removable flash memory cards. ... Announced for the first time by SanDisk Corporation at CeBIT 2003, the miniSD joined the MemoryStick Duo and xD-Picture Card at this small Form factor. ... Apple iPod nano (third-generation), a best-selling flash-based player An embedded hard drive-based player (Creative ZEN Vision:M) An MP3 CD player (Philips Expanium) More commonly referred to as an MP3 player, a digital audio player (DAP) is a portable consumer electronics device that stores, organizes and... The Nintendo GameCube is an example of a popular video game console. ... For the video game system, see Nintendo Entertainment System. ... The Wii (pronounced as the pronoun we, IPA: ) is the fifth home video game console released by Nintendo. ... Nintendo DS homebrew is software written for the Nintendo DS handheld games console by hobbyist programmers, as opposed to a software/game production company. ... The Nintendo DS (sometimes abbreviated NDS or more commonly DS) is a handheld game console developed and manufactured by Nintendo. ... Sony Corporation ) is a Japanese multinational corporation and one of the worlds largest media conglomerates with revenue of $66. ... The PlayStation 3 , trademarked PLAYSTATION®3,[3] commonly abbreviated PS3) is the third home video game console produced by Sony Computer Entertainment; successor to the PlayStation 2. ... The GP2X is an open-source, Linux-based handheld video game console and media player created and sold by GamePark Holdings of South Korea. ... OMAP is a Texas Instruments proprietary microprocessor for multimedia applications. ... Digital Audio Broadcasting (DAB), also known as Eureka 147, is a technology for broadcasting of audio using digital radio transmission. ... GPS redirects here. ... A digital photo frame is a picture frame that displays digital photos without the need for printing them first. ... A stylised illustration of a personal computer A personal computer (PC) is a computer whose original sales price, size, and capabilities make it useful for individuals, intended to be operated directly by an end user, with no intervening computer operator. ... USB redirects here. ... PCI Express bus card slots (from top to bottom: x4, x16, x1 and x16), compared to a traditional 32-bit PCI bus card slot (bottom) In computer architecture, a bus is a subsystem that transfers data or power between computer components inside a computer or between computers, and a bus... An ultraportable IBM X31 with 12 screen on an IBM T43 Thin & Light laptop with a 14 screen A laptop computer, or simply laptop (also notebook computer, notebook and notepad) is a small mobile computer, typically weighing 3-12 pounds (around 1. ... Amazon. ... Amazon Kindle is an electronic book (e-book) service launched in the United States by Amazon. ... Panasonic (パナソニック Panasonikku) is an international brand name for Japanese electric products manufacturer Matsushita Electric Industrial Co. ... A plasma display is an emissive flat panel display where light is created by phosphors excited by a plasma discharge between two flat panels of glass. ... It has been suggested that In car entertainment be merged into this article or section. ... For other uses, see MP3 (disambiguation). ... Windows Media Audio (WMA) is an audio data compression technology developed by Microsoft. ... Note: USB may also mean upper sideband in radio. ... JumpDrive redirects here. ...

Compact digital cameras

SD/MMC cards have replaced Toshiba's SmartMedia as the dominant memory card format used in compact digital cameras. In 2001 SmartMedia had achieved nearly 50% use, but by 2005 SD/MMC had achieved over 40% of the digital camera market and SmartMedia’s share had plummeted, with cards not being easily available in 2007. Toshiba Corporations headquarters (Center) in Hamamatsucho, Tokyo Toshiba Corporation sales by division for year ending March 31, 2005 Toshiba Corporation ) (TYO: 6502 ) is a Japanese multinational conglomerate manufacturing company, headquartered in Tokyo, Japan. ... A 128MB SmartMedia flash memory card. ...

A majority of the world’s leading digital camera manufacturers use SD in their product lines, including Casio, Canon, Nikon, Pentax, Kodak, Panasonic and Konica Minolta. Two major brands, however, have stuck to their own proprietary formats in their cameras: Olympus using xD cards, and Sony using Memory Stick. Fuji prior to 2007 also used xD cards exclusively, but has added SD functionality to all of their models since then. Casio Computer Co. ... Canon Inc. ... For other uses, see Nikon (disambiguation). ... Pentax Corporation ) is a Japanese company founded in 1919 as Asahi Optical Joint Stock Co. ... Eastman Kodak Company (NYSE: EK) is a large multinational public company producing photographic equipment. ... Panasonic (パナソニック Panasonikku) is an international brand name for Japanese electric products manufacturer Matsushita Electric Industrial Co. ... Konica Minolta Holdings, Inc. ... This article refers to a mountain in Greece. ... The xD-Picture Card is a type of flash memory card, used mainly in digital cameras. ... Sony Corporation ) is a Japanese multinational corporation and one of the worlds largest media conglomerates with revenue of $66. ... This article is about Sonys proprietary memory format. ... Fujifilm Holdings Corporation or Fujifilm ) is a Japanese company known for its photographic film and cameras. ... The xD-Picture Card is a type of flash memory card, used mainly in digital cameras. ...

Digital SLR cameras

SD has not conquered the market for Digital SLR cameras. In this market CompactFlash remains the most popular format due to its historically lower price/capacity ratio, better read/write performance, and the availability of larger capacities. A digital single lens reflex or DSLR camera is a single-lens reflex camera (SLR) which records images using an electronic sensor (Usually a CCD or CMOS chip) instead of film. ... A 32 MB High Speed CompactFlash Type I card CompactFlash (CF) was originally developed as a type of data storage device used in portable electronic devices. ...

As of 2007, however, an increasing number of models use SD/MMC/SDHC cards exclusively: Pentax's complete line since the 2004 *istDS; Nikon's 2005 D50, 2006 D40, 2006 D80, 2007 D40X, and 2008 Nikon D60; and most recently Canon's 2008 EOS 450D/Rebel XSi. 2007 is a common year starting on Monday of the Gregorian calendar. ... PENTAX *ist DS is a digital SLR camera produced by Pentax. ... The D50 is Nikons entry-level Digital single-lens reflex camera model. ... The D40 is the least expensive, and most compact[2] member of Nikons entry-level digital SLR range, announced November 16, 2006. ... The D80 is a prosumer digital single-lens reflex camera model announced by Nikon August 9th, 2006. ... The D40 is the most inexpensive member of Nikons entry-level digital SLR range, announced 2006-11-16. ...

Several high-end professional DSLRs — notably Canon's EOS-1Ds Mark III and EOS-1D Mark III — support both CompactFlash and SD for greater flexibility and storage capacity. The EOS-1Ds Mark III is a digital SLR camera body by Canon Inc. ... The EOS 1D Mark III is a professional 10. ...

See also

• SD Card Association
• Comparison of memory cards
• MultiMediaCard
• P2 card

The SD Card Association markets and promulgates technical standards for SD Card technology: Secure Digital card and miniSD Card. ... This table provides summary of comparison of various flash memory cards, as of 2007. ... A 32 MB MultiMediaCard MultiMediaCard A 128 MB RS-MMC card and an adapter An RS-MMC card with adapter attached The MultiMediaCard (MMC) is a flash memory memory card standard. ... DVCPRO P2 (P2 is short form for Professional Plug-In) is a professional digital video storage media format introduced by Panasonic in 2004, and especially tailored to ENG applications. ...

References

Year 2006 (MMVI) was a common year starting on Sunday of the Gregorian calendar. ... is the 339th day of the year (340th in leap years) in the Gregorian calendar. ... 2008 (MMVIII) is the current year, a leap year that started on Tuesday of the Anno Domini (or common era), in accordance with the Gregorian calendar. ... is the 133rd day of the year (134th in leap years) in the Gregorian calendar. ... Year 2006 (MMVI) was a common year starting on Sunday of the Gregorian calendar. ... is the 199th day of the year (200th in leap years) in the Gregorian calendar. ... 2008 (MMVIII) is the current year, a leap year that started on Tuesday of the Anno Domini (or common era), in accordance with the Gregorian calendar. ... is the 133rd day of the year (134th in leap years) in the Gregorian calendar. ... This table provides summary of comparison of various flash memory cards, as of 2007. ... is the 268th day of the year (269th in leap years) in the Gregorian calendar. ... Year 2006 (MMVI) was a common year starting on Sunday of the Gregorian calendar. ... PDF is an abbreviation with several meanings: Portable Document Format Post-doctoral fellowship Probability density function There also is an electronic design automation company named PDF Solutions. ... Year 2007 (MMVII) was a common year starting on Monday of the Gregorian calendar in the 21st century. ... is the 54th day of the year in the Gregorian calendar. ...

External links

• maxim-ic.com, Maxim Semiconductor app note describing SD with source code
• mmca.org, MultiMedia Card Association
• sandisk.com, SanDisk SD Card Product Manual 1.9 This is no longer available, but you can get it from cs.ucr.edu (v1.9)
• sandisk.com, SanDisk memory card device compatibility lookup
• sdcard.org, SD Memory Card Physical Layer Specification, version 1.01 (pdf)
• sdcard.org, Simplified SDIO Card Specification
• sdcard.org, Simplified Physical Layer Specification Useful info on the differences of SD vs. SDHC
• gadgetspage.com, Understanding SD Card Speeds
• k9spud.com, Interfacing dsPIC30F4013 to SD Cards
• pinouts.ru, Secure Digital connector pinout and signals
• sdcard.org, SD Card Association
• embwise.com, SD/SDIO Operating System independent Bus Driver
• hjreggel.net, Comparison of practically all Memory CARDS
• elm-chan.org, How to Use an MMC
• memorybits.co.uk, SD Gaming Card Primer
• eeproductcenter.com, SD/SDHC controller for mobile devices from Cypress Semiconductor Corp