Detect card?
SD/MMC booting
Success
Failed
No card connected
Get the booting file
Get raw data
Raw mode
detected?
Configures the card(RCA)
MMC or SD card
Yes
No
Initializes SD/MMC driver
init-016
Failure
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Device Initialization by ROM Code
Figure 26-24. MMC/SD Booting
26.4.7.6.1 Connectivity Constraints
SD/MMC port 1 can support I/O in two modes, 1.8 V or 3.0 V, provided the correct voltage supply is
connected to the VDDS_SDMMC1 pin. Hardware provides the mechanism to detect the presence of 3.0 V
on VDDS_SDMMC1. If the hardware does not detect 3.0 V, the ROM code assumes 1.8-V voltage is
present and configures the I/O pads accordingly.
To enable the hardware to generate the correct levels on the SD/MMC interface, the following connectivity
constraints must be respected.
3559
SWPU177N – December 2009 – Revised November 2010
Initialization
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