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RS-MMC card and an adapter]] The Multimedia Card ('''MMC''') is a Serial Interface , but newer versions of the specification allow transfers of 4 or sometimes even 8 bits at a time. They have been more or less superseded by Secure Digital Card s, but still see significant use because MMC cards can be used in any device which supports SD cards. Typically, an MMC card is used as storage media for a portable device, in a form that can easily be removed for access by a PC . For example, a Digital Camera would use an MMC card for storing image files. With an MMC reader (typically a small box that connects via USB or some other serial connection, although some can be found integrated into the computer itself), a user could copy the pictures taken with the digital camera off to his or her computer. Modern computers, both laptops and desktops, often have SD slots, which can read MMC cards. MMC cards are currently available in sizes up to and including 4 GB , and are used in almost every context in which Memory Card s are used, like Cellular Phone s, Digital Audio Player s, Digital Camera s and PDA s. Since the introduction of Secure Digital Card few companies build MMC slots into their devices, but the slightly thinner, pin-compatible MMC cards can be used in almost any device that supports SD cards. A handful of companies, most notably Nokia , still support MMC exclusively, however. OPEN STANDARD This technology is an Open Standard available to any Company who wants to improve upon it or develop products for it. REDUCED-SIZE MULTIMEDIA CARD (RS-MMC) MMC cards also come in a smaller form factor, of about half the size: 24 mm × 16 mm × 1.5 mm. This alternate form factor is known as Reduced-Size Multimedia Card, or '''RS-MMC''', and was introduced in 2004 . RS-MMC cards are simply smaller MMC cards; by using a simple mechanical adapter to elongate the card, an RS-MMC card can be used in any MMC (or SD) slot. RS-MMC cards are currently available in sizes up to and including 2 GB. The only significant hardware licensors of RS-MMC cards are Nokia and Siemens, who often use RS-MMC in their Series 60 Symbian Smartphone s, the Nokia 770 Internet Tablet (Nokia), and generations 65 and 75 (Siemens). Newer RS-MMC cards, used in Nokia's newer phones (like the Nokia 6630 and Nokia 6680 ), support a lower Voltage (1.8 V instead of 3 V) mode to reduce battery demand, and these lower-voltage RS-MMC cards, known as Dual Voltage Reduced Size MMC (DV-RS-MMC), and can be marketed as MMC'''mobile''' when they meet the MMC''mobile'' card standards. These low-voltage cards are backwards compatible with older RS-MMC devices. The dual voltage cards, and the MMC''mobile'' are part of the MMC 4.x standards. MMC 4.X AND SECUREMMC Standard 4.x (4.0, 4.1, etc.) was released in 2005 (MMCA System Specification 4.1). This new standard involves the higher performance MMC4 (with the same basic MMC form factor but more pins) called MMC''plus'', and RS-MMC4, marketed as MMC''mobile''. MMC''mobile'' mirrors the old RS-MMC in that it has the same connections and connection standard, but is about half the size as regular MMC cards. Also in the works is secureMMC, which will feature encryption features similar to Secure Digital or MagicGate Memory Sticks. EXTERNAL LINKS
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