Datasheet

AS4C16M16SA-C&I
Confidential 15 Rev. 3.0 Mar. /2015

Write Burst Length (A9)
This bit is used to select the write burst mode. When the A9 bit is "0", the Burst-Read-Burst-Write mode is
selected. When the A9 bit is "1", the Burst-Read-Single-Write mode is selected.
Table 11. Write Burst Length
A9
Write Burst Mode
0
Burst-Read-Burst-Write
1
Burst-Read-Single-Write
Note: A10 and BA0, 1 should stay “L” during mode set cycle.
9 No-Operation command
(RAS# = "H", CAS# = "H", WE# = "H")
The No-Operation command is used to perform a NOP to the SDRAM which is selected (CS# is Low).
This prevents unwanted commands from being registered during idle or wait states.
10 Burst Stop command
(RAS# = "H", CAS# = "H", WE# = "L")
The Burst Stop command is used to terminate either fixed-length or full-page bursts. This command is
only effective in a read/write burst without the auto precharge function. The terminated read burst ends after
a delay equal to the CAS latency (refer to the following figure). The termination of a write burst is shown in
the following figure.
CLK
COMMAND
T0 T1 T2 T3 T4 T5 T6
READ A NOP NOP NOP
Burst
Stop
NOP NOP NOP
T7 T8
NOP
CAS# Latency=2
t
CK2
, DQ
CAS# Latency=3
t
CK3
, DQ
DOUT A
0
DOUT A
1
DOUT A
2
DOUT A
3
DOUT A
0
DOUT A
1
DOUT A
2
DOUT A
3
The burst ends after a delay equal to the CAS# Latency
Figure 16 .Termination of a Burst Read Operation
(Burst Length
＞
4, CAS# Latency = 2, 3)
CLK
DQ
T0 T1 T2 T3 T4 T5 T6
DIN A
0
DIN A
1
DIN A
2
don’t care
T7 T8
COMMAND
NOP WRITE A NOP NOP
Burst
Stop
NOP NOP NOP NOP
Figure 17 .Termination of a Burst Write Operation
(Burst Length = X)