MultiMediaCard Product Manual
SanDisk MultiMediaCard Product Manual Rev. 2 © 2000 SANDISK CORPORATION
51
Table 5-4 Block Oriented Read Commands (Class 2)
Cmd
I n d e x
T y p e
Argument
R e s p
Abbreviation
Command Description
CMD16
ac
[31:0] block
length
R1
SET_BLOCKLEN
Selects a block length (in bytes) for all
following block commands (read and
write).
1
CMD17
adtc
[31:0] data
address
R1
READ_SINGLE_
BLOCK
Reads a block of the size selected by the
SET_BLOCKLEN command.
2
CMD18
adtc
[31:0] data
address
R1
READ_MULTIPLE_BL
OCK
Continuously send blocks of data until
interrupted by a stop or a new read
command.
CMD19
Reserved
Table 5-5 Sequential Write Commands (Class 3)
Cmd
I n d e x
T y p e
Argument
R e s p
Abbreviation
Command Description
CMD20
adtc
[31:0] data
address
R1
WRITE_DAT_UNTIL_
STOP
Writes data stream from the host starting
at the supplied address, until a
STOP_TRANSMISSION follows.
CMD21.
. .
CMD23
Reserved
Table 5-6 Block Oriented Write Commands (Class 4)
Cmd
I n d e x
T y p e
Argument
R e s p
Abbreviation
Command Description
CMD24
adtc
[31:0] data
address
R1
WRITE_BLOCK
Writes a block of the size selected by the
SET_BLOCKLEN command.
3
CMD25
adtc
[31:0] data
address
R1
WRITE_MULTIPLE_
BLOCK
Continuously writes blocks of data until a
STOP_TRANSMISSION follows.
CMD26
Not Applicable
CMD27
adtc
[31:0] don’t cares* R1
PROGRAM_CSD
Programming of the programmable bits of
the CSD.
*Note:
The bit places must be filled but the value is irrelevant.
1)
The default block length is as specified in the CSD (512 bytes). A set block length of less than 512 bytes will
cause a write error. The only valid write set block length is 512 bytes. CMD16 is not mandatory if the default is
accepted.
2)
The data transferred must not cross a physical block boundary.
3)
All data blocks are responded to with a data response token followed by a busy signal. The data transferred
must not cross a physical block boundary.