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WiFi SD Card hacked - useful for the prop? — Parallax Forums

WiFi SD Card hacked - useful for the prop?

Cluso99Cluso99 Posts: 18,069
edited 2013-08-17 20:09 in Propeller 1
I just noticed on Hack-a-day that the Transcend WiFi SD card has been easily hacked.
http://hackaday.com/2013/08/12/hacking-transcend-wifi-sd-cards/

I wondered if this could be a simple way to add both SD and WiFi to a Prop chip, so thought I would post this here.

Now, I am going to add those special words of wisdom... "it's impossible" ;)

Comments

  • Phil Pilgrim (PhiPi)Phil Pilgrim (PhiPi) Posts: 23,514
    edited 2013-08-12 22:17
    This is definitely an intriquing development. I first took notice of such cards with the "Eye-Fi," but they were pretty much tied to a single use and non-hackable. The Transcend card shows more promise.

    -Phil
  • TorTor Posts: 2,010
    edited 2013-08-13 01:15
    Very interesting. I ordered a Transcend card immediately after seeing that. I bet they'll sell more of them now that it's out that they're actually small Linux computers with 16GB or 32GB on-board storage.. with an ARM CPU. Their original single purpose of using wi-fi instead of simply putting the camera card into a card reader to quickly dump the images isn't very interesting, so I had no intention of buying one. Until now.

    -Tor
  • yetiyeti Posts: 818
    edited 2013-08-13 03:36
    http://www.mikrocontroller.net/topic/303547#3255785 wrote:
    Noch gerade ein Test gemacht: Die WLAN Reichweite ist max. 5 Meter.
    The WLAN range of these card seems to be 5 meters max...
  • Heater.Heater. Posts: 21,230
    edited 2013-08-13 04:15
    Fantastic story of the hack. He made very good use of many features of the Perl language which is used to drive al lot of features on the card, to get there.

    Finally. a way to run Linux on your Propeller, just get a DIP Prop and glue one of those WIFI SD cards on top:)
  • Heater.Heater. Posts: 21,230
    edited 2013-08-13 04:22
    Cluso,
    I wondered if this could be a simple way to add both SD and WiFi to a Prop chip, so thought I would post this here.

    A Simple hack job there might be:

    1) Prop writes file(s) to a specified location on SD card as usual.
    2) The SD cards ARM sees that file(s) change at that location.
    3) ARM sends file(s) out over WIFI, using whatever protocol.
    4) Likewise in reverse.

    Of course what we would like is a more direct connection from SD interface to ARM without going through the file system, more like some serial channel, no idea about that.
  • DogPDogP Posts: 168
    edited 2013-08-13 04:25
    I'm not sure that the card works in SPI mode... according to this comment, it didn't work for them: http://hackaday.com/2013/08/12/hacking-transcend-wifi-sd-cards/#comment-1039452 . If that's the case, then it's probably not too useful for us on the Prop, unless it's something that can be fixed in software. It seems that some devices have the ARM UART brought out to test points, so you could interface to that... at a much slower rate than the SD interface though.

    Also, it looks like the PQI Air card works the same: http://www.newegg.com/Product/Product.aspx?Item=N82E16820141601 , except uses Micro SD, rather than built-in flash.

    DogP
  • Heater.Heater. Posts: 21,230
    edited 2013-08-13 04:32
    Of course you will want to fix up all those security holes before attaching it to your beloved Prop.

    Strangely enough there is a thread going on now about using the PII as a self hosted system so as to be secure where it was pointed out that many peripherals you might use are vulnerable. This is a classic case.
  • Cluso99Cluso99 Posts: 18,069
    edited 2013-08-13 17:51
    The PQI Air is an interesting alternative (using a separate microSD for flash storage).

    I wondered too if the SPI interface works. Maybe it's time to do a full SD driver??
  • DogPDogP Posts: 168
    edited 2013-08-13 18:54
    Cluso99 wrote: »
    The PQI Air is an interesting alternative (using a separate microSD for flash storage).

    I wondered too if the SPI interface works. Maybe it's time to do a full SD driver??
    Yeah... if SPI doesn't work on the Transcend, it could be just that their flash doesn't support it (I believe SDHC/XC aren't required to), so I wonder if you use the PQI with an old Micro SD card (or SDHC that's verified to have SPI mode), if maybe it'll work. I guess it depends how the flash is connected between the device and the ARM (do they both talk to the Micro SD card, or does the device talk to the ARM only in SD mode, which does all the talking to the Micro SD).

    It'd also be nice to know how it's connected, to see if there's an efficient way to make this work as a WiFi device (map a device to the SD card space, and have a protocol for making a network connection through it). It could easily be done by writing a file, having the ARM monitor that file, process the command, and send back the relevant data... but if it's actually writing the flash, and having Busybox constantly looking at the flash, that seems inefficient (and possibly a quick way to wear out the flash).

    And yeah... a full SD driver on the Prop would be nice... I know there's extra overhead involved, but I'd imagine the 4-bit parallel interface would more than make up for the extra computations required.

    Pat
  • FernandFernand Posts: 83
    edited 2013-08-14 03:05
    There was talk of using memory on networked Windows machines to do ReadyBoost, i.e. as a cache for the disk-based virtual memory system. SD cards are commonly used for ReadyBoost.

    If a Prop had a fast interface into such a networked SD card, with the WiFi handler mapping it on the other side as a "drive", maybe on the Windows side the paging system could map it into Windows memory and thus create shared memory? Use Memory Mapped Files as the access technique? The advantage of Memory Mapped Files is that the OS handles all the complexity, like flushing "dirty" chunks, no need to be "constantly looking".
  • DogPDogP Posts: 168
    edited 2013-08-16 12:20
    BTW, I got my PQI card the other day... it's really cool, and there's actually no need to "hack" anything. Out of the box, it runs an open wireless access point, with Telnet and FTP running with no password (kinda scary). So you can just telnet in and do whatever you want. I also received my Transcend card, though I haven't plugged it in yet (it was in my mailbox as I was heading out of town).

    I don't know for sure, but it seems likely that the PQI card doesn't support SPI mode either. I only quickly tested it, but I put a Micro SD card in a device (which I think runs SPI mode) using a regular Micro SD card adapter, and it worked perfectly... then I used the PQI card as the adapter and it didn't work. Yet in another board (which uses SD mode, not SPI), it had no problem booting Linux from the Micro SD card using the PQI as the adapter.

    I'll be bringing these cards with me to the Propellerpowered Expo tomorrow... hopefully someone will have a Prop board that uses SD that maybe we can play around with these on.

    Pat
  • prof_brainoprof_braino Posts: 4,313
    edited 2013-08-17 07:01
    Notes on connecting SD to prop using adapter, resistors, and 4 wires; takes about 10 minutes if the soldering iron is hot

    http://code.google.com/p/propforth/wiki/SDsetupREVISITED
  • DogPDogP Posts: 168
    edited 2013-08-17 20:09
    prof_braino wrote: »
    Notes on connecting SD to prop using adapter, resistors, and 4 wires; takes about 10 minutes if the soldering iron is hot

    http://code.google.com/p/propforth/wiki/SDsetupREVISITED
    Yep... I've got a Prop w/ SD at home, but I'm out of town for the Propellerpowered Expo. I just had a few minutes to try it in a couple devices before I left town.

    Unfortunately, nobody at the expo had a Prop w/ SD (everyone uses Micro SD).

    Pat
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