Datasheet

438
SAM9X25 [DATASHEET]
11054E–ATARM–10-Mar-2014
Figure 30-6. Burst Write Access, Row Closed, DDR2-SDRAM Device
Figure 30-7. Burst Write Access, Row Closed, SDR-SDRAM Device
A write command can be followed by a read command. To avoid breaking the current write burst, Twtr/Twrd (bl/2 + 2 = 6
cycles) should be met. See Figure 30-8 on page 439.
Trp = 2
Trcd = 2
SDCLK
Row a col a
A[12:0]
NOP PRCHG NOP ACT NOP WRITE NOP
COMMAND
0
BA[1:0]
DQS[1:0]
Da Db Dc Dd De Df Dg Dh
D [15:0]
3 0 3
DM[1:0]
Row a Col a
NOP PRCHG NOP ACT NOP WRITE NOP
0
Da Db
Dc
Dd
De
Df
Dg
Dhs
F 0 F
Trp
Trcd
BST NOP
SDCLK
A[12:0]
COMMAND
BA[1:0]
D[31:0]
DM[3:0]