Secure digital input/output interface (SDIO)
RM0090
DocID018909 Rev 11
The basic transaction on the MultiMediaCard/SD/SD I/O bus is the command/response
transaction. These types of bus transaction transfer their information directly within the
command or response structure. In addition, some operations have a data token.
Data transfers to/from SD/SDIO memory cards are done in data blocks. Data transfers
to/from MMC are done data blocks or streams. Data transfers to/from the CE-ATA Devices
are done in data blocks.
Figure 321. SDIO “no response” and “no data” operations
Figure 322. SDIO (multiple) block read operation
Operation (no response)
Operation (no data)
SDIO_CMD
SDIO_D
From host to card(s)
From host to card
From card to host
Response
Command
Command
ai14734
ai14735
Command
Response
Data
b
lock crc
Data
b
lock crc
Data
b
lock crc
Block read operation
Multiple
b
lock read operation
Data stop operation
From host to card
From card to host
data from card to host
Stop command
stops data transfer
Command
Response
SDIO_CMD
SDIO_D