In order to make compact devices to reduce the size of all components. This applies to the storage media, especially removable. It is difficult to make a compact record player, a CD-players, too, need a bigger pocket. CompactFlash, SmartMedia and Memory Stick have been following the attempts to make mobile devices, not just portable, but also the pocket. But there is no limit to perfection. Technological progress has made possible an almost impossible. These are two relatively new standards, Multimedia Card and SecureDigital. These cards weigh less than two grams, and the size they are similar to ordinary postage stamp. SD slightly thicker than MMC. In addition to their small size, they have a number of other remarkable qualities. Card-baby does not get damaged by heat or cold (even though the sauna is better not to take ... to anything they are there). Even a fall from a height of several feet onto the asphalt, they do not break. All this, and no moving parts and non-volatile memory ensures high reliability of data storage for many years. SD / MMC-Card issued a volume of 4, 8, 16, 24, 32, 64 and 128MB. In the near future will be more spacious designs.
MultiMediaCard
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In autumn 1997 SanDisk and Siemens / Infineon was represented standard MultiMediaCard. It was jointly developed by a group of 14 companies. Now the Association MMCA has grown to 90 members, among whom there are many well-known companies, including Casio, Fuji, Hitachi, HP, Mitsubishi, Nokia, SanDisk, Siemens, Symbian. Standard was created for use in various multimedia devices such as audio players, cell phones, PDAs, GPS-receivers, photo and video cameras, etc. MMC card provides quick access to data, low power consumption and high reliability. These qualities have allowed standards to attract a large number of developers and manufacturers of the very different techniques. In the market there are many small devices, the creation of which would not have been possible without the MMC. Can you imagine how big would the phone Siemens SL45 or hours-MP3-Player from Casio, if they used as a CompactFlash expansion card? It is unlikely that someone would carry such monsters. In general, despite competition from cheaper SmartMedia, MultiMediaCard found his niche in the market and has been used safely for years. But there were found willing to do even better.
Secure Digital
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April 25, 1999 Matsushita Electric, Toshiba and SanDisk have signed an agreement whose purpose was to create a standard Secure Digital. It companies within the MMCA, developing the ideas contained in the MultiMediaCard. Now the SD Card Association is already more than two hundred companies, many of whom have announced their products that use Secure Digital cards to store information. They include Alpine, Canon, Casio, Handera, HP, IBM, Kenwood, Microsoft, Mitsubishi, Olympus, Palm, Samsung and many others. The main advantage of the standard, is used cryptographic protection against illegal copying of information. In addition, Secure Digital provides copyright protection, according to methods developed in the SDMI (Secure Digital Music Initiative). Similar principles are used in standard DVD Audio. Thus, the recording industry tries to control the market of digital music. After all, digital music is very easy to propagate, even easier than audio-CD. Just copy the file and write to any other carrier. Fast-spreading standard is not satisfied with MMC media corporations because of the possibility of copying of information stored on these cards. Guide SD Card Association has repeatedly stated that they plan to push the market all the major media in use today.Miniature carriers must replace compact discs, mini discs, and even ordinary cassettes. Subject to support from the owners of media content, these plans are very real. Another favorable factor is that in the SD-slot can be placed and MMC-card (but not vice-versa). In an effort to provide customers with maximum functionality, producers certainly prefer a universal SD-slot uncontested MMC. To write-protect a mechanical switch, similar to what everyone can see on a normal three-inch floppy disk, as well as MemoryStick. This simple but effective protection is not enough cards MMC. Despite the volume indicated on the card, in fact, free space on it will be less. The fact is that according to the specifications of the standard SD, each megabyte climbs a hundred or more kilobytes. This is to ensure the infamous copy protection. Even more interesting information can be seen on the site SanDisk. In tamoshnem FAQ has this question: "Why is my SD / MMC-card actually has a smaller volume than that which is written on it." The answer is simply amazing. It explains that the MB version of SanDisk is 1000Kb and not 1024KB. It's funny that the text is called "MB SanDisk" and "megabyte Microsoft". I recall the anecdote about something that is different from a complete novice programmer :-)). 64 megabytes of SanDisk "are 60" MB Microsoft ". As a result, say, a 16MB card is only 13Mb of free space. With the price of an average of $ 10 above and to the extent of 10-20% less, you can hardly advise SD-card for regular users, not too concerned about the protection of its MP3-music, download a Napster `s or on MP3.com. Most likely, the future of this standard is associated with the recording industry. He probably will get accustomed and in the corporate market, where data protection is also important. And if he gets this recognition, the price of memory cards can fall.
Devices
List of products that support the MMC, is large enough. Apparently, most of all interested in this standard, manufacturers of various MP3-players. Among them are very extravagant designs, for example, SpringBoard-module Innogear MiniJam MP3 Player for the Handspring Visor, cell phones Siemens SL-45 and LG MP-Cion MP3 Phone. Ericsson developed an attachment to a cell phone, which, again, allows you to listen to MP3-music. He also has a Casio watches WMP-1V. What do you think, what they feature? That's right, they are also the MP3-player. But the MMC-cards are used not only for music storage. There are a number of devices, including Cassiopeia EM-500, Nokia 9110 Communicator, which can record there any other information. And JVC, Thompson and Panasonic have released a series of camcorders with MMC-slot. Agfa makes cameras. But perhaps the most unusual devices are the printer NV-MPXS from Panasonic and gadgets PocketPet, developed by Japanese mobile giant NTT DoCoMo for wireless access to email.
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In contrast, devices that support memory card Secure Digital, while few in number. Became the first compact camera Panasonic iPalm PV-DC3000. She appeared in September last year. Now the company's website has information on road and even CD-player, portable recorder, photo and video cameras. Corporation Toshiba, which also participated in developing the standard, introduced MP3-Player. And this spring in the list of SD-devices, there are three representatives of the market of handheld computers. These are two models from Palm, m500 and m505, as well as another PalmOS-device, Handera 330. In general, the trend is: cheap Taiwanese mp3-players is not quite, equipment mostly serious (car CD-player, for example, costs $ 1400). This situation is explained by the fact that the standard SecureDigital officially not ready yet. Of course, memory cards are available for a long time, and the device does not appear yesterday, but work on it continues. Until such time as the documents will not put the last point, boom, SD-compatible devices are expected.
Prospects
Following the submission of new Palm'ov with SD / MMC-slot, we were talking about using it to increase not only memory but also functionality. More precisely, on additional devices connected to the Palm. At various exhibitions Palm presented prototypes of various devices, but mostly it was just a dummy. Probably until the work is completed on a standard Secure Digital, these devices are not submitted. The rest, apparently, the development will be to increase the amount of memory to 256MB and above. But even here there are interesting events. Not so long ago, for example, was presented a draft Secure Multimedia Card - in fact, MMC updated in line with modern realities. Moreover, he may call into question the future Secure Digital, because the technology embodied in this new standard will take into account all the latest trends, but will build on the solid foundation of proven technology and extensive customer base. Well, any competition is usually on hand to consumers. So we'll see a battle of the giants of our acceptance to you, after all, chooses all the same buyer.
Prices
| MMC | SD |
| 16 MB | $ 27.99 | $ 37.99 |
| 24 MB | $ 39.94 | * |
| 32 MB | $ 44.99 | $ 59.99 |
| 64 MB | $ 79.99 | $ 89.99 |
| 128 MB | $ 119.99 | * |
* Secure Digital card volume of 24 and 128MB are available, but in the shops until they were found.
Specifications:
| MMC | SD |
| Dimensions | 3.2 x 2, 4x1, 4 mm | 3.2 x 2, 4x2, 1 mm |
| Number of contacts | 7 | 9 |
| Voltage | 2.7V - 3.6V | 2.7V - 3.6V |
| Data transfer rate | 2Mb/sek | 2Mb/sek |
| Weight | 1.5 oz | 1.5 oz |
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