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High Capacity microSD Card

Transcend Information Inc.

16

Note that for current SD Memory Cards that field must be always 0_0110_010b (032h) which is equal to 25MHz - the

mandatory maximum operating frequency of SD Memory Card.

In High-Speed mode, that field must be always 0_1011_010b (05Ah) which is equal to 50MHz. And when the timing

mode returns to the default by CMD6 or CMD0 command, its value will be 032h.

The SD Memory Card command set is divided into subsets (command classes). The card command class register CCC

defines which command classes are supported by this card. A value of ‘1’ in a CCC bit means that the corresponding

command class is supported.

This field is fixed to 9h, which indicates READ_BL_LEN=512 Byte.

This field is fixed to 0, which indicates partial block read is inhibited and only unit of block access is allowed.

This field is fixed to 0, which indicates write access crossing physical block boundaries is always disabled in High

apacity SD Memory Card.

C

This field is fixed to 0, which indicates read a

disabled in High Capacity SD Memory Card.

ccess crossing physical block boundaries is always

Defines if the configurable driver stage is integrated on the card. If set, a driver stage register (DSR)must be

implemented also.