Chapter 4 – SD Card Protocol Description
Revision 2.2
SanDisk SD Card Product Manual
© 2004 SanDisk Corporation
4-46
12/08/04
Stop Transmission Received after Last Data Block—Card Busy Programming
Stop Transmission Received after Last Data Block—Card becomes Busy
Erase, Set and Clear Write Protect Timing
The host must first tag the start (CMD32) and end (CMD33) addresses of the range to be
erased. The erase command (CMD38), once issued, will erase all the selected write blocks.
Similarly, set and clear write protect commands start a programming operation as well. The
card will signal “busy” (by pulling the DAT line low) for the duration of the erase or
programming operation. The bus transaction timings are the same as given for stop tran
command in the “
Stop Transmission Received after Last Data Block—Card Busy
Programming
” diagram above.
Re-selecting a Busy Card
When a busy card, which is currently in the dis state, is reselected it will reinstate its busy
signaling on the data line. The timing diagram for this command/response/busy transaction
is the same as given for stop tran command in the “
Stop Transmission Received after Last
Data Block—Card becomes Busy
” diagram above.
4.13 Timing
Values
Table 4-24 defines all timing values.
Table 4-24
Timing Values
Value Min. Max.
Unit
N
CR
2
64
Clock
cycles
N
ID
5
5
Clock
cycles
N
AC
2
See Note
Clock cycles
N
RC
8
---
Clock
cycles
N
CC
8
---
Clock
cycles
N
WR
2
---
Clock
cycles
Note—The host calculates the maximum read access time as follows:
N
AC
(max)= 100 ((TAAC * f
PP
) + (100 * NSAC)) ;
f
PP
is the interface clock rate and TAAC & NSAC are given in the CSD Register.
CMD
DAT
S T
Z
Z
E
S T
Z Z
Card Response
Z
Content
******************************************************************
Z Z P
S
E Z Z
E
Card is Programming
Host Command
Content
***
T Content
CRC
CRC
Z
Host Command
N
CR
Cycles
S L
L
P
CMD S T
DAT
Z
Z
S T
Z Z
Card Response
Z
Content
*********************
Z Z
S
E Z Z
E
Card is Programming
Host Command
Content
P
T Content
CRC
CRC
Z
Host Command
N
CR
Cycles
Z Z Z Z Z
Z
S
Z Z Z
L
Z Z
L
***
E
P