In addition to the features supported by the RSI on previous Blackfin processors (e.g. BF51x), the RSI on BF60x supports following new features:
- Support for the Boot Mode for MMC - The MMC cards following MMC specification revision 4.3 or later support two smaller memory partitions in addition to the user area exclusive to store boot data. These partitions can be read by the host to read the boot data in two different modes:
- Normal Boot Mode - booting is done by pulling CMD pin low for 74 cycles.
- Alternate Boot Mode - booting is done by issuing CMD0 with argument 0xFFFFFFFA.
The RSI on BF60x processors support both these modes with the help of dedicated registers, control and status1 bits, and interrupts.
- Support for Sleep Mode for MMC - The MMC cards following MMC specification revision 4.3 or later support Sleep Mode to minimize the power consumption. In this state the memory device reacts only to the commands RESET (CMD0) and SLEEP/AWAKE (CMD5). All the other commands are ignored by the memory device. The RSI on BF60x processors support this mode with the help of dedicated registers, status bits and interrupts.
- Support for Card Busy/Ready detection - For some commands (e.g. CMD6), the card may assert the BUSY signal by driving DAT0 line low two cycles after the end bit of the command. The DAT0 is asserted low by the card even when it is busy programming the data written to it. The RSI on BF60x processors support card busy/ready detection with the help of dedicated status bits and interrupts.