EM639325
EtronTech
Burst Definition, Addressing Sequence of Sequential and Interleave Mode
•
Table 6. Burst Definition
Start Address
Burst Length
Sequential
Interleave
A2
X
X
X
X
X
X
0
0
0
0
1
A1
X
X
0
0
1
1
0
0
1
A0
0
1
0
1
0
1
0
1
0
1
0
1
0
1
0, 1
1, 0
0, 1, 2, 3
1, 2, 3, 0
2, 3, 0, 1
0, 1
1, 0
0, 1, 2, 3
1, 0, 3, 2
2, 3, 0, 1
3, 2, 1, 0
2
4
3, 0, 1, 2
0, 1, 2, 3, 4, 5, 6, 7
1, 2, 3, 4, 5, 6, 7, 0
2, 3, 4, 5, 6, 7, 0, 1
3, 4, 5, 6, 7, 0, 1, 2
4, 5, 6, 7, 0, 1, 2, 3
5, 6, 7, 0, 1, 2, 3, 4
6, 7, 0, 1, 2, 3, 4, 5
7, 0, 1, 2, 3, 4, 5, 6
n, n+1, n+2, n+3, …255, 0,
1, 2, … n-1, n, …
0, 1, 2, 3, 4, 5, 6, 7
1, 0, 3, 2, 5, 4, 7, 6
2, 3, 0, 1, 6, 7, 4, 5
3, 2, 1, 0, 7, 6, 5, 4
4, 5, 6, 7, 0, 1, 2, 3
5, 4, 7, 6, 1, 0, 3, 2
6, 7, 4, 5, 2, 3, 0, 1
7, 6, 5, 4, 3, 2, 1, 0
1
0
0
1
8
1
1
1
1
Full page location = 0-255
Not Support
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.
Figure 17. Termination of a Burst Read Operation
(Burst Length＞4, CAS# Latency = 2, 3)
T0
T1
T2
T3
T4
T5
T6
T7
T8
CLK
Burst
Stop
COMMAND
READ A
NOP
NOP
NOP
NOP
NOP
NOP
NOP
The burst ends after a delay equal to the CAS# latency
CAS# latency=2
DOUT A0
DOUT A1
DOUT A0
DOUT A2
DOUT A1
DOUT A3
DOUT A2
t
CK2, DQ
CAS# latency=3
CK3, DQ
DOUT A3
t
Rev. 2.1
15
Aug. /2015
ETRON [ ETRON TECHNOLOGY, INC. ]
