SDRAM
AS4SD8M16
Austin Semiconductor, Inc.
FIGURE 1: Mode Register Definition TABLE 1: Burst Definition
BURST STARTING
ORDER OF ACCESSES WITHIN A BURST
LENGTH
COLUMN TYPE = SEQUENTIAL TYPE = INTERLEAVED
A0
2
0
1
0-1
1-0
0-1
1-0
A1 A0
0
0
1
1
0
1
0
1
0-1-2-3
1-2-3-0
2-3-0-1
3-0-1-2
0-1-2-3
1-0-3-2
2-3-0-1
3-2-1-0
4
8
A2 A1 A0
0
0
0
0
1
1
1
1
0
0
1
1
0
0
1
1
0
1
0
1
0
1
0
1
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
Cn, Cn+1, Cn+2, Cn+3,
Cn+4…
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
Full
Page
(y)
n=A0-A8
(location 0-y)
Not Supported
…Cn-1,
Cn…
NOTES:
1. For full-page access: y=512
2. For a burst length of two, A1-A8 select the block-of-two burst;
A0 selects the starting column within the block.
3. For a burst length of four, A2-A8 select the block-of-four burst;
A0-A1 selects the starting column within the block.
4. For a burst length of eight, A3-A8 select the block-of-eight burst; A0-A2
selects the starting column within the block.
5. For a full-page burst, the full row is selected and A0-A8 select the starting
column.
6. Whenever a boundary of the block is reached within a given sequence
above, the following access wraps within the block.
7. For a burst length of one, A0-A8 select the unique column to be accessed,
and mode register bit M3 is ignored.
Austin Semiconductor, Inc. reserves the right to change products or specifications without notice.
AS4SD8M16
Rev. 0.5 04/05
5
AUSTIN [ AUSTIN SEMICONDUCTOR ]
