SD and MMC Cards

Q. Where can I find more information on SmartMedia^TM

A. For details, visit the official site of the SSFDC Forum.
http://www.ssfdc.or.jp/english/faq/
The SSFDC Forum is a nonprofit voluntary organization intended to establish SmartMedia^TM as the de facto industry standard and spread its use worldwide. Please do not request of them information on prices or dates of release.

Q. FAQ for SD Memory Card

A. For details, visit the official site of the SD Forum.

http://www.sdcard.org/

Detailed technical information on the SD Memory Card is provided to SD Association members only. Membership is limited to corporate entities. Some information, however if possible, will be disclosed to the public at this site.

Q. Does the SD Memory Card support hot plug-in and removal?

A. Yes. In the case of SmartMedia^TM, this depends on the connectors.

Q. For how many cycles of insertion/removal is the SD Memory Card guaranteed?

A. For 10,000 insertion/removal cycles.

Q. What is the price difference between MMC and SD technology products

A. The SD Memory Card will be more expensive than the SmartMedia^TM card. This is due to a higher security specification.

Q. What is the SD Memory Card's upward compatibility with the MMC (MultiMediaCard)?

A. The SD Memory and MMC cards have the same height and width dimensions (32 mm x 24 mm), but they differ in thickness. Due to its higher capacity, the SD Memory Card, at 2.1 mm thick, is 0.7 mm thicker than the MMC card. These cards have the same contact pin layout, except that the SD Memory Card has two additional pins. When we indicate "upwardly compatible," we mean compatibility in physical specifications and lower-level logic specifications. In other words, the MMC card fits the SD Memory Card slot. Also, there is no problem with reading and writing files from/to MMC, as the SD Memory and MMC cards have the same FAT structure. But, these cards may not be compatible in the applications layer, because the applications SW specification of each card may be different

Q. Is the SD Memory Card compatible with the MMC?

A. You can transfer only non-secure data from an MMC to an SD Memory Card; you cannot transfer secure data.

Q. Can I use an SD Memory Card instead of an MMC in an MP3 player?

A. No. The SD Memory Card doesn't fit the slot. Also, the logic format for music is different. SD audio players comply with SD audio standards. An SD audio player can only play music recorded in the SD standard audio format. Similarly, an SD audio player cannot read the data on an MMC formatted for an MP3 player.

Q. Does the SD Memory Card have a special mechanism to deliver music?

A. Each step for content download is encrypted in a different way. When data is downloaded to a SD Memory Card, it is further encrypted by means of an SD Memory Card encryption scheme (CPRM: content protection for recordable media). Also, a SD Memory Card is designed to prevent decryption while data is written into the card.

Q. What are the SD Memory Card specifications?

A. The SD Memory Card specifications are provided to those who have entered into a nondisclosure agreement (NDA) with the SD association.

Q. How many times can data be rewritten into flash memory?

A. Flash memories withstand 200,000 to 300,000 data write operations (varies slightly, depending on service conditions).