Signal Descriptions

A.6 MMC and SD flash card interface

The MMC/SD card sockets provides nine pins that connect to the card when it is inserted into the socket. Figure A-7 shows the pin numbering and signal assignment. In addition, the socket contains switches that are operated by card insertion and provide signaling on the CARDINx and MCI_WPROT signals.

DATA2

 

9

 

DATA3

 

1

 

CMD

 

2

 

Ground

 

3

 

VDD

 

4

 

Clock

 

5

 

Ground

 

6

 

DATA0

7

 

8

DATA1

 

Ground

Write protect

Card in

Ground

Figure A-7 MMC/SD card socket pin numbering

The MMC card uses seven pins, and the SD card uses all nine pins. The additional pins are located as shown in Figure A-7 with pin 9 next to pin 1 and pins 7 and 8 spaced more closely together than the other pins. Figure A-8 shows an MCI card, with the contacts face up.

1 2 3 4 5 6 7

Figure A-8 MMC card

A-8

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ARM DUI 0224I

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ARM ARM DUI 0224I manual MMC and SD flash card interface, Figure A-7 MMC/SD card socket pin numbering