Datasheet

T
T
T
S
S
S
4
4
4
~
~
~
1
1
1
6
6
6
G
G
G
U
U
U
S
S
S
D
D
D
H
H
H
C
C
C
2
2
2
-
-
-
P
P
P
3
3
3
4~16GB microSDHC Class 2 Card + Reader P3
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.
• 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.