Transcend HD Video Card Series, Техническое описание

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HD Video Card Series
4GB~16GB SDHC6 HD Video Card
Transcend Information Inc.
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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.
• CCC
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.
•
READ_BL_LEN
This field is fixed to 9h, which indicates READ_BL_LEN=512 Byte.
•
READ_BL_PARTIAL
This field is fixed to 0, which indicates partial block read is inhibited and only unit of block access is allowed.
•
WRITE_BLK_MISALIGN
This field is fixed to 0, which indicates write access crossing physical block boundaries is always disabled in High
Capacity SD Memory Card.
• READ_BLK_MISALIGN
This field is fixed to 0, which indicates read access crossing physical block boundaries is always
disabled in High Capacity SD Memory Card.
•
DSR_IMP
Defines if the configurable driver stage is integrated on the card. If set, a driver stage register (DSR)must be
implemented also.