
MultiMediaCard
TM
101
Sep.22.2005
Revision 0.3
7.23.3 Data write
Single Block Write
The host may deselect a card (by raising the CS) at any time during the card busy period (refer to the given timing dia-
gram). The card will release the DataOut line one clock after the CS going high. To check if the card is still busy it needs to
be reselected by asserting (set to low) the CS signal. The card will resume busy signal (pulling DataOut low) one clock
cycle after the falling edge of CS.
Figure 7-22 : SPI Single Block Write
Multiple Block Write
The timing behavior of the multiple block write transaction starting from the command up to the first data block is identical
to the single block write. Figure 7-23 describes the timing between the data blocks of a multiple block write transaction.
Timing of the ‘Stop Tran’ token is identical to a standard data block. After the “Stop Tran” token is received ny the card, the
data on the DataOut line is undefined for one byte (N
BR
), after which a Busy token may appear. The host may deselect
and reselect the card during every busy period between the data blocks. Timing for toggling the CS signal is identical to
the Single block write transaction.
Figure 7-23 : SPI Multiple Block Write
CS
H L
* * * * * * * * * * * * * * * * * * * *
L L L L
L L L L H H H L L L L
←
N
EC
→←
N
DS
→
H H * * H X * * X H H H H
←
N
CS
→
X H * * H Write Cmd H H H H H H H H * * H Data Block H H
←
N
CR
→
Z Z H H H
* * * * H * * H
Card Rsp H H H H H H H
←
N
WR
→
DataIn
DataOut
Data Resp
Busy
L Z Z Z Busy H
CS
L
* * * * * * * * * * * * * * * * * * * *
L L L L L L L L L L L L L L L L L L L L
←
N
WR
→
←
N
WR
→
DataIn
H Data Block H H H H H H H H * * H Data Block H H H H H H H H * * H Stop Tran H H H H H
←
N
BR
→
DataOut
H H H H H
Data Resp
Busy
H H H H H H H
Data Resp
Busy
H H H H H H X * * X Busy