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1.5.8.10
Copy Bit
The content of a MultiMediaCard can be marked
as an original or a copy using the copy bit in t h e
CSD register. Once the Copy bit is set (marked as
a copy) it cannot be cleared. The Copy bit of t h e
MultiMediaCard is programmed (during test and
formatting on the manufacturing floor) as a copy.
The MultiMediaCard can be purchased with t h e
copy bit set (copy) or cleared, indicating the card
is a master. This feature is implemented in t h e
MultiMediaCard controller firmware and not
with a physical OTP cell.
1.5.8.11
The CSD Register
All
the
configuration
MultiMediaCard is stored in the CSD register.
The
MSB
bytes
of
manufacturer data and the two least significant
bytes contain the host controlled data—the card
Copy and write protection and the user ECC
register.
The host can read the CSD register and alter t h e
host controlled data bytes using the SEND_CSD
and PROGRAM_CSD commands.
1.5.9
SPI Mode
The SPI mode is a secondary communication
protocol for MultiMediaCards. This mode is a
subset of the MultiMediaCard protocol, designed
to communicate with an SPI channel, commonly
found in Motorola's (and lately a few other
vendors') microcontrollers.
1.5.9.1
Negotiating Operating Conditions
The operating condition negotiation function of
the MultiMediaCard bus is not supported in SPI
mode. The host must work within the valid
voltage range (2.7 to 3.6) volts of the card.
SanDisk MultiMediaCard Product Manual Rev. 2 © 2000 SANDISK CORPORATION
information
of
t h e
the
register
contain
MultiMediaCard Product Manual
1.5.9.2
Card Acquisition and Identification
The card acquisition and identification function of
the MultiMediaCard bus is not supported in SPI
mode. The host must know the number of cards
currently connected on the bus. Specific card
selection is done via the CS signal.
1.5.9.3
Card Status
In SPI mode only 16 bits (containing the errors
relevant to SPI mode) can be read out of t h e
MultiMediaCard status register.
1.5.9.4
Memory Array Partitioning
Memory partitioning in SPI mode is equivalent to
MultiMediaCard mode. All
commands are byte addressable.
1.5.9.5
Read and Write Operations
In SPI mode, only single block read/write mode is
supported.
1.5.9.6
Data Transfer Rate
Same as for the MultiMediaCard mode when t h e
card is operating in single block read/write mode.
1.5.9.7
Data Protection in the
MultiMediaCard
Same as for the MultiMediaCard mode.
1.5.9.8
Erase
Same as in MultiMediaCard mode.
1.5.9.9
Write Protection
Same as in MultiMediaCard mode.
read and write
15
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