Connect with us

Sony Magic Gate Memory Cards

Discussion in 'Electronic Basics' started by techie_alison, Jan 21, 2006.

Scroll to continue with content
  1. Hello,

    I hope you can help here. I've just started working for a new employer and
    one of the first projects I have is to develop and interface/reader for
    Sony's memory cards. CF and SD cards, IDE and SCSI I've done before and the
    information was pretty much readily available. In this case however, Sony's
    protocols for communication with their cards at an embedded level is a bit
    obscure and non-existant.

    The MG technology I believe is an encryption algorithm applied to the cards
    to 'lock' them, it was originally pushed with the Playstation 2 as allowing
    the storage of online customer information, bank account details, passwords

    Is the MG function always enabled? Because if it is I'm dead in the water
    from the moment go without that algorithm.

    Would anyone have any experience in interfacing with these cards, please any
    info? It'd help me out loads as I'm just sitting here doing all of the
    other background work surrounding the project in the meantime.

    Any help very much appreciated,

    Aly :)
  2. Pal

    Pal Guest

    Hi again Aly...

    Did a bit of a search, but the news doesn't look good.

    Not strictly related to your issue, but contains discussion on the
    encryption system, which seems to fall into the "pay as a million in
    licence fees, or we sue you to death" catregory.


  3. larwe

    larwe Guest

    It's not in the least obscure; it's merely unavailable without signing
    a license. You also cannot use the Memory Stick compatibility logo
    without such a license.

    History: In 1999 or thereabouts, when Memory Stick was emerging, Sony
    made 85% of the interface documentation public and a license to use
    Memory Stick was free for the asking. A few years later, they clamped
    down and made it something like SD - you had to pay a lot to get in the
    club. At that time they hid all the public documentation (though if you
    want a copy, I can give you one).

    I don't have the MagicGate specification and couldn't disclose it if I
    did. But the specification for vanilla Memory Stick is written in such
    a way as to imply that the DRM feature isn't turned on until you use
    it. As further evidence in support of this, modern Memory Stick media
    work with cameras designed for pre-MagicGate sticks.
  4. Rich Grise

    Rich Grise Guest

    Hey, you bullshat your way into the job, let's see if you can bullshit
    your way through the task at hand!

    Good Luck!
  5. That was certainly uncalled for Rich.

    What in the posting smells of bullshit to you?

    But now that I review your posting, your signal to
    noise ratio is less than 10%

    Is this a pot-and-kettle thing?

  6. Rich Grise

    Rich Grise Guest

    That you got the job and now you seem unable to perform the job you
    were hired for.

    And I really, really wanted to use the word, "bullshat". ;-P

    Good Luck!
  7. So you don't have the information I'm looking for then? You're welcome to
    come round to my house and go through my redundant chips drawer and get them
    all working without datasheets.

    Actually, my company would just love to employ someone like you who can
    solve all of the open tickets. Send on your resume.
  8. Alex Colvin

    Alex Colvin Guest

    That you got the job and now you seem unable to perform the job you

    Would you expect to hire only people experienced with the specific parts
    you intend to use? That would make it pretty hard to develop anything new.

    Maybe that explains why 8051s are still so common.

    In most of my work, I'm hired to find out what I need to know. I've even
    asked questions on usenet, though the answers often resemble this one.
  9. Alex Colvin

    Alex Colvin Guest

    So you don't have the information I'm looking for then? You're welcome to
    and as we know, datasheets have all the information you need to get the
    part working...
  10. Agreed.

    A logic analyser was one of the best bits of kit I ever bought, in that
    usually I can solve a puzzle with an equal amount of personal energy as to
    requesting information via usenet/forums with a load of hassle from people
    who are still bemused by flashing LEDs.

    The rule of thumb regarding usenet (and which a few of the engineers I work
    with advise on) is simply to never post, never answer questions. Simply not
    to get involved. The majority of our ideas and methods of doing things are
    thrashed out in a continuous yahoo conference which does seem to work well.
    As for the Sony thing, without that algorithm it aint going nowhere, I can't
    implement full compatiability without it. It would have generated about
    10,000 units with the dies etched in China, and it's the company's decision
    not to sign contracts with Sony so therefore it's a management decision.
    ABS braking anyone???
  11. larwe

    larwe Guest

    They should be thankful you haven't found a way into the algorithm.
    Poking about in Sony's DRM schemes without a license is a guaranteed
    way to a lawsuit. I don't recall for sure, but I think there are patent
    considerations - I am QUITE sure there are DMCA problems.
  12. Yep, the US side of the company had initially thrown $100k figures about for
    a full licence. Also while researching this it's become clear that
    certainly in the US it's a criminal act to try to disect something such as
    an algorithm.

    While I haven't tried to unravel the algorithm I'd hope that it's
    sufficiantly secure not to be able to do so. My 3rd year thesis was about
    cryptography, with the main danger pointed out that sensitive highly
    encrypted data (military for example) could be captured today and revealed
    in 5 years time when processing power has evolved. So while the bad guys
    might not have access to the data now, in time they will do. Equally so,
    the Sony MG algorithm will come out in years to come.
  13. Clint Sharp

    Clint Sharp Guest

    Wow, welcome to the land of the free. There's precedent set in English
    law IIRC that specifically enables you to reverse engineer (Mars vending
    and coin mechs) a protocol, I think you'd have to be able to prove
    'clean room' techniques via documentation to be safe though. Can't quite
    believe that you can't take a logic analyser and scope to equipment that
    you've paid for without risking getting your butt fried. Hopefully we'll
    be able to hunt lawyer instead of foxes if they ever become that much of
    a nuisance over here.
  14. larwe

    larwe Guest

    DMCA trumps interoperability if you are building a "circumvention
    device". It requires a lawsuit to determine what is and is not a
    circumvention device. So you might win, but it will cripple you

    Walt Disney bought the land of the free. Soon there will be a tax on
    PIC12* series micros because they can be used to make PlayStation
    Doesn't matter how clean your room is:

    a) If you're infringing on a patent (lawsuit will determine yes or no
    to this) then you have to negotiate a license, no matter how you worked
    out how to implement it.

    b) If you're delving into DMCA, be prepared for a long and agonizing
    battle regardless of where the merits (if I can use such a word) lie.

    The best US case law on this is a case of Lexmark vs. someone who was
    making refurbished ink cartridges. Lexmark had some kind of crypto
    protocol between the printer and the cartridge to prevent people from
    doing this (the cart becomes useless once it is empty and the printer
    won't print unless it can talk to the chip in the cart). Lexmark sued
    someone who worked out the details and faked the chips. The defendant
    won. But it was not an easy victory and this particular situation (MG
    cards) is not the same by a long shot.
Ask a Question
Want to reply to this thread or ask your own question?
You'll need to choose a username for the site, which only take a couple of moments (here). After that, you can post your question and our members will help you out.
Electronics Point Logo
Continue to site
Quote of the day