Chapter 5 – SPI Protocol
Revision 2.2 SD Card Product Manual
© 2004 SanDisk Corporation 5-18 12/08/04
Host Command to Card Response—Card is Busy
Card Response to Host Command
5.23.3 Data Read
The following timing diagram describes all single block read operations with the exception
of SEND_CSD command.
Single Block Read Timing
The following figure describes a Stop Transmission operation in case Multiple Block Read
occurs.
Multiple Block Read Timing
Reading the CSD Register
The following timing diagram describes the SEND_CSD command bus transaction. The
timeout values for the response and the data block are N
CR
(because the N
AC
is still
unknown).
Reading the CSD Register
X H H H
Z Z H H H
H L L *******************
6 byte cmd H H H H H
H H H********
H H X X X H H
Card resp. L Z Z Z
H
L L L L L H H
N
CS
N
EC
N
CR
CS
Data In
Data Out
L L L H H H LL
H H H H H H H
H H Busy
Busy
H H H X X
H H H H Z
L
N
DS
N
EC
H H H H
H H H H
L L L *******************
****************
H H H1 or 2 byte resp. ********************* H H
H
L H H H H
N
CR
CS
Data In
Data Out
L
H
H
H X X X X
H H Z Z Z
L
H 6-byte command
H H H H H
H
L
X H H H
Z Z H H H
H L L ***************************************
Read Command H H H H H
H H H********
H
Card resp. H H
H
L L L H H H H
N
CS
N
CR
CS
Data In
Data Out
L
H
H H
H X X X X
H H Z Z Z
N
EC
***********************
Data BlockH H HH
N
AC
X H H H H
L L L *******************
stop tran cmd H H H H H ***************
data transfer to host card response H
N
CS
N
CR
CS
Data In
Data Out
L
H
H
<2clk>
X H H H
Z Z H H
H L L *******************
read command
********** card response H H
H
L H H H H
N
CR
CS
Data In
Data Out
L
H H X X X X
H H Z Z Z
L
*********************
H H H H H
H
L
H H H HH H H HH data blk
H
N
CS
N
CX
N
EC