Product manual

5-3 SanDisk miniSD Card Product Manual, Rev. 1.1 © 2003 SANDISK CORPORATION
Figure 5-2. Read Operation—Data Error
In the case of a Multiple Block Read operation, every transferred block has a 16-bit CRC suffix. The Stop
Transmission command (CMD12) will actually stop the data transfer operation (the same as in SD Bus mode).
From
host to
card(s)
DataIn
DataOut
Command
Data from
card to host
Command
Response
From
card to
host
Response
Data block crc Data block crc
From
card to
host
Stop
Transmission
Command
Figure 5-3. Multiple Block Read Operation
5.1.4. Data Write
In SPI mode, the miniSD Card supports single block or multiple block write operations. Upon reception of a valid
write command (miniSD Card CMD24 or CMD25), the card will respond with a response token and will wait for a
data block to be sent from the host. CRC suffix and start address restrictions are identical to the read operation (see
Figure 5-4). The only valid block length, however, is 512 bytes. Setting a smaller block length will cause a write
error on the next write command.
From
Host to
Card
From
Card to
Host
DataIn
DataOut
Command
Data From
Host to Card
Data_
Response
Busy
Data
Response
and Busy
From Card
Response
Data Block
Start
Block
Token
New Command
from Host
Command
Figure 5-4. Single Block Write Operation
Command
DataIn
Command
Response
Data Error
From Host
to Card
From Card
to Host
Data Error
Token from
Card to Host
Next Command
DataOut