MMC/flash with ATA/ATAPI interface

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Hi

I am going to use the Cypress CY7C68xxx series for USB mass storage devices (which pops up in windows explorer as an external disk drive) to give my project either an IDE/ATA interface or an interface to removebal storage medias as different MMC cards . However, I am not quite sure aboute which MMC cards that supports the ATA interface like PCMCIA ATA disk drives does. If you know aboute any ref. designs using other card types, I would be glad to know. I would also like to know aboute other chips like the Cypress chip (I am aware aboute SMSC) if you know aboute them wich also supports other interfaces

Thanks in advance

W

Regards
Vidar (Z)

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"The fool wonders, the wise man asks"

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MMC cards do not have a ATA compatible interface (unless you provide the electronics for it). MMC use a serially clocked data method to read and write data. Compact Flash are the only devices that implement the ATA interface in flash devices.

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Quote:
MMC cards do not have a ATA compatible interface (unless you provide the electronics for it). MMC use a serially clocked data method to read and write data.

Umm, nope... I do not agree since MMC only stands for "MultiMediaCard" and is a designation for several card types used in, well, multimedia equipments like viderecorders, cameras, mp3-players and another portable devices. MMC says nothing aboute which interface to be used. Yes, most of them, like SD and others, uses a seriell interface but that is not a requirement for MMC. However, you did answer my question by pointing me to the Compact Flash card (Yet another MM-Card), so thank you anyway. :wink:

Regards
Vidar (Z)

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"The fool wonders, the wise man asks"

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Please update your knowledge base.

I'm sorry, but you're incorrect. MultiMediaCard (MMC) is ONE card type, a stamp sized card, and the predecessor for SD cards which is backwards compatible.
The name MMC DOES state in detail, the interfaces to the card, both electrical and protocol wise.
MMC cards have NO similarity to CF cards, Memory Sticks, SmartMedia or any other card like that, except for containing memory and being small.

There's LOTS on information about MMC, SD and CF cards available at the Sandisk website. Also visit the MMCA organisation for info specific to MMC cards.

/Jesper
http://www.yampp.com
The quick black AVR jumped over the lazy PIC.
What boots up, must come down.

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Initial this was correct, but the designation MMC has been missused for many years (atleast outside technical forums) and there has been articles written, which I offcourse cant find at this moment, which says that MMC is now more a common description for a group of multi media cards in stead of spesifying only one card type, this is also the reason of why you offten find SD cards written like SD/MMC.

Please correct me if I am wrong. Like one older man once said it, I am man enough too stand for my opinions, but I am also man enough too admit it if I am proved wrong later on.

Thanks

Regards
Vidar (Z)

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"The fool wonders, the wise man asks"

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zainka wrote:
why you offten find SD cards written like SD/MMC.

Because they have common hardware interface and command set, just a diffrent package.