MMC/SD Host Controller
7-132
In SPI mode 2, transfers to the MMC/SD card follow the SPI protocol. MMC
clock is enabled and the SPI clock is disabled. MMC protocol must be imple-
mented in software when using this mode since the MMC interface acts as a
generic SPI port and does not utilize the MMC-specific features available in
MMC/SD mode.
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00: MMC/SD mode (MMC/SD cards using MMC protocol)
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01: SPI mode 1 (for serial flash or others SPI slave devices)
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10: SYSTEST mode
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11: SPI mode 2 (MMC/SD cards using SPI protocol)
Values after reset are low (2 bits).
Power Up-Control (Power_Up)
This bit (11) must be set to 1 prior to any valid transaction to either MMC/SD
or SPI memory cards.
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When 1, the card is considered powered up and the controller core is
enabled.
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When 0, the card is considered powered down (system dependant) and
the controller core logic in pseudoreset state. That is, the MMC_STAT
register flags are reset, the FIFO pointers are reset, any access to DATA
register has no effect, a write into MMC_CMD register is ignored, and
setting of MMC_SPI:start to 1 is ignored.
J
0: Powered-down/pseudoreset state
J
1: Powered-up/normal operation mode
Value after reset is low.