487
8331B–AVR–03/12
Atmel AVR XMEGA AU
36.14 SDRAM 4-bit write
Figure 36-44.
Single write
Precharg
e Al
l Banks
Bank Adr
0x0
D[3:0]
Row Adr
Col Adr
0x400
Acti
ve
Wr
ite
NOP
*
NOP
**
Single write
D[7:4]
* The number of NOPs is equal to ROWCOLDLY[2:0] (ROWCOLDLY = 1 is shown)
** The number of NOPs is equal to WRDLY[1:0] + 1 (WRDLY = 0 is shown)
*** The number of NOPs is equal to RPDLY[1:0] (RPDLY = 1 is shown)
CLK
CKE
CAS
RAS
DQM
BA[1:0]
A[11:0]
D
Clk
PER2
WE
CS