Detailed Command Description - SanDisk SDMB-16-470 - 16 MB MultiMedia Card Product Manual

MultiMediaCard Product Manual
6.2.1.1

Detailed Command Description

The following table
description of the SPI bus commands. The
responses are defined in section 6.2.2. This table
below lists all MultiMediaCard commands. A
"yes" in the SPI mode column indicates that t h e
command is supported in SPI mode. With these
restrictions, the command class description in t h e
CSD is still valid. If a command does not require
Table 6-1 Description of SPI Bus Commands
CMD S P I Argument
I N D E X Mode
CMD0 Yes None
CMD1 Yes None
CMD2 No
CMD3 No
CMD4 No
CMD5 reserved
CMD6 reserved
CMD7 No
CMD8 reserved
CMD9 Yes None
CMD10 Yes None
CMD11 No
CMD12 No
CMD13 Yes None
CMD14 No
CMD15 No
CMD16 Yes [31:0] block
length
CMD17 Yes [31:0] data
address
1) The only valid block length for write is 512 bytes. The valid block length for read is 1 to 512 bytes. A set block
length of less than 512 bytes will cause a write error. The card has a default block length of 512 bytes. CMD16 is
not mandatory if the default is accepted.
2) The start address and block length must be set so that the data transferred will not cross a physical block
boundary.
66
provides a detailed
R e s Abbreviation
p
R1 GO_IDLE_STATE
R1 SEND_OP_COND
R1 SEND_CSD
R1 SEND_CID
R2 SEND_STATUS
R1 SET_BLOCKLEN
R1 READ_SINGLE_
BLOCK
SanDisk MultiMediaCard Product Manual Rev. 2 © 2000 SANDISK CORPORATION
an argument, the value of this field should be set
to zero. The reserved commands are reserved in
MultiMediaCard mode as well.
The binary code of a command is defined by t h e
mnemonic symbol. As an example, the content of
the Command field for CMD0 is (binary) '000000'
and for CMD39 is (binary) '100111.'
Command Description
Resets the MultiMediaCard
Activates the card's initialization
process.
Asks the selected card to send its card-
specific data (CSD).
Asks the selected card to send its card
identification (CID).
Asks the selected card to send its status
register.
Selects a block length (in bytes) for all
following block commands (read and
1
write).
Reads a block of the size selected by the
SET_BLOCKLEN command.
2