DocID018909 Rev 11
RM0090
Secure digital input/output interface (SDIO)
1067
CMD37
Reserved. This command index cannot be used in order to maintain backward compatibility with older
versions of the MultiMediaCards
CMD38 ac
[31:0] stuff bits
R1
ERASE
Erases all previously selected write
blocks.
Table 168. Erase commands (continued)
CMD
index
Type
Argument
Response
format
Abbreviation
Description
Table 169. I/O mode commands
CMD
index
Type
Argument
Response
format
Abbreviation
Description
CMD39 ac
[31:16] RCA
[15:15] register
write flag
[14:8] register
address
[7:0] register data
R4
FAST_IO
Used to write and read 8-bit (register) data
fields. The command addresses a card and a
register and provides the data for writing if
the write flag is set. The R4 response
contains data read from the addressed
register. This command accesses
application-dependent registers that are not
defined in the MultiMediaCard standard.
CMD40 bcr
[31:0] stuff bits
R5
GO_IRQ_STATE
Places the system in the interrupt mode.
CMD41 Reserved
Table 170. Lock card
CMD
index
Type
Argument
Response
format
Abbreviation
Description
CMD42 adtc
[31:0] stuff bits R1b
LOCK_UNLOCK
Sets/resets the password or locks/unlocks
the card. The size of the data block is set
by the SET_BLOCK_LEN command.
CMD43
...
CMD54
Reserved
Table 171. Application-specific commands
CMD
index
Type
Argument
Response
format
Abbreviation
Description
CMD55
ac
[31:16] RCA
[15:0] stuff bits
R1
APP_CMD
Indicates to the card that the next command
bits is an application specific command rather
than a standard command
CMD56
adtc
[31:1] stuff bits
[0]: RD/WR
Used either to transfer a data block to the card
or to get a data block from the card for general
purpose/application-specific commands. The
size of the data block shall be set by the
SET_BLOCK_LEN command.