Hello ALL, I am working on the At89c5132 usb microcontroller and wants to program the multimedia card protocols. Can anyone help out with what the Command Index and Command argument contain? I read that the first bit of the 1 byte command index is '0' (start bit), second bit '1' (start transmission)....what about the other 6 bits? And what are the attributes of the command argument (4 bytes) .i.e. the bits representation. The microcontroller only connects to just one mmc card. Thanks