HB288032MM1 Datasheet, PDF (20/80 Pages) Hitachi Semiconductor – MultiMediaCard 32 MByte

HB288032MM1
• ECC
Defines the ECC code that was used for storing data on the card. This field is used by the host (or
application) to decode the user data. The following table defines the field format.
ECC Type
ECC
0
1
2–15
ECC type
none (default)
BCH (542,512)
reserved
Maximum number of correctable bits
none
3
—
The content provider or customer defines which kind of error correction may be used to protect the contents
of the HB288032MM1. This value is programmable.
• CRC
The CRC register contains the check sum for the CSD content. The check sum is computed by the
following formulas: Generator polynomial:
G(x) = x⁷ + x³ + 1
M(x) = CSD[127]∗x¹¹⁹ +...+ CSD[8]∗x⁰ CRC[6...0] = Remainder [(M(x)∗x⁷)/G(x)]
The user has to recalculate a new CRC after defining a new CSD.
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