We currently have a (client's) product that uses an MMC (SPI mode) for datastorage, the client would like to change this to SD card.
After searching the web, I did find the SD card simplified physical layer spec, but not much else. The
From what I understand, it is possible to access an SD card as if it where an MMC (both in SPI mode), with only a minor difference in initialization. Is this true?
The client would also like the possiblity to change to 4-bit mode later on. All signals will be routed through programmable logic. We will not be using any of the security features.
Has anyone found more usefull information on the web? Any tips?