11.2 Interfacing with an SD Card

The SD (Secure Digital) Card is a nonvolatile memory card format used as mass storage memory in mobile devices.

Secure Digital Multimedia Card (SDMMC) Controller

The SAMA7D65 SOM Series includes two Secure Digital Multimedia Card (SDMMC) interfaces that support the MultiMedia Card (e.MMC) specification V4.51, the SD Memory Card specification V3.0, and the SDIO V3.0 specification. They are compliant with the SD Host Controller Standard V3.0 specification.

The two interfaces can be connected to a standard SD card interface.

SDMMCx Card Connector

The board features two standard MMC/SD card connectors, connected to SDMMC1 and SDMMC2. Both interface communications are based on a 4-pin interface (clock, command, four data and power lines).

Table 11-5. SDMMCx Interface Configurations
Interface InstanceIO SetPin No.PIOPin NameDescription
SDMMC11144PB23SDMMC1_CKSD card/e.MMC clock signal
140PB22SDMMC1_CMDSD card/e.MMC command Line
141PB24SDMMC1_DAT0SD card/e.MMC data lines
143PB25SDMMC1_DAT1
142PB26SDMMC1_DAT2
145PB27SDMMC1_DAT3
SDMMC2196PC28SDMMC2_CKSD card/e.MMC clock signal
95PC27SDMMC2_CMDSD card/e.MMC command line
93PC29SDMMC2_DAT0SD card/e.MMC data lines
94PC30SDMMC2_DAT1
92PC31SDMMC2_DAT2
91PD0SDMMC2_DAT3