RM0090: Reference manual - STMicroelectronics

Secure digital input/output interface (SDIO) RM0090
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 307. SDIO “no response” and “no data” operations
Figure 308. SDIO (multiple) block read operation
SDIO_CMD
SDIO_D
SDIO_CMD
SDIO_D
Operation (no response) Operation (no data)
843/1416 Doc ID 018909 Rev 3
From host to card(s) From host to card From card to host
From host to card From card to host
Command Response
Command Command
Block read operation
Response
Data block crc Data block crc Data block crc
Multiple block read operation
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data from card to host Stop command
stops data transfer
Command Response
Data stop operation
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