Chapter 4 – SD Card Protocol Description
Revision 2.2
SanDisk SD Card Product Manual
© 2004 SanDisk Corporation
4-2
12/08/04
Figure 4-2
Multiple Block Read Operation
The block-write operation uses a simple busy signaling of the write operation duration on
the DAT0 data line (see Figure 4-3) regardless of the number of data lines used for
transferring the data.
Figure 4-3
Multiple Block Write Operation
Command tokens have the coding scheme shown in Figure 4-4.
Figure 4-4
Command Token Format
CMD
From host
to card(s)
DAT
Data from
card to
host
Response
Command
Block write operation
Data stop operation
Response
From card
to host
"Stop" command stops
data transfer
Command
Data block
CRC
Busy
Data block
CRC
Busy
Multiple Block Write Operation
CRC OK
response
and busy
from card
"Start" bit
always 0
"End" bit
always 1
Total length = 48 bits
0
Content
CRC
Command content: command and
address information or parameter,
protected by 7-bit CRC checksum
1
1
"Transmitter" bit:
1=host command
CMD
From host
to card(s)
DAT
Data from
card to
host
Response
Command
Block read operation
Data stop operation
Response
Data block
CRC
Data block
CRC
From card
to host
"Stop" command stops
data transfer
Data block
CRC
Command
Multiple block read operation