I don't have a particular project in mind, but it seems like having512+MB of memory at my disposal for microcontroller projects would be quite amazing. From a few of the posts I've read, and the limited specs I could find, it seems like Secure Digital (SD) memory cards allow for an SPI interface (serial) and run anywhere from 0-25Mhz. (I've interfaced to CompactFlash cards and Cardbus, and SPI seems much easier, in concept)
But a few of the articles I found about SD cards briefly talked about their security features and the need to pay the "Secure Digital People" for specs on the device and perhaps even some proprietary information on how to talk to the chip such that it will actually store and retrieve data. Is this correct?!
If there is any known work around, I would love to hear it. I guess that brings me to my two questions, shown below:
- What is the pinout for the SD card?
- What are the protocol specs to address the SD card, put it in read/write mode, and then access data? (a PDF datasheet would be helpful here)
I'm sure if there was a simple way to tap into the SD card, only requiring the small number of standard SPI pins, microcontroller projects with high storage capabilities would spring up everywhere since the pin count is so small and the memory sizes keep getting larger by the day. :) Thanks for your help!
Best Regards, Adam Kumpf