IS42RM16800F

A0

A1

A2

A3

A4

A5

A6

A7

A8

A9

A10

A11

Figure4: Mode Register Definition

BA0

BA1

WB

0

CAS Latency

BT

Burst Length

Address Bus

0

1

2

3

4

5

6

10

987

11

Mode Register (Mx)

00

0

0

12

13

0

M9

Write Burst Mode

0

Burst Read and Burst Write

1

Burst Read and Single Write

M3

Burst Type

0Sequential

1Interleave

M6

M5

M4

CAS Latency

000

Reserved

001

-

010

2

011

3

100

Reserved

101

Reserved

1

1

0

Reserved

M2

M1

M0

Burst Length

M3 = 0

M3 = 1

000

1

1

001

2

2

010

4

4

011

8

8

1

0

0

Reserved

Reserved

1

0

1

Reserved

Reserved

Burst Type

Accesses within a given burst may be programmed to be either sequential or interleaved; this is referred to as the burst type and is

selected via bit M3. The ordering of accesses within a burst is determined by the burst length, the burst type and the starting column

add ess as sho n in Table 3

1

1

0

Reserved

111

Reserved

1

0

1

Reserved

Reserved

1

1

0

Reserved

Reserved

111

Full Page

Reserved

Note: M13/M12(BA1/BA0) must be set to “0/0” to select Mode Register (vs. the Extended Mode Register)

address, as shown in Table 3.

Table 3: Burst Definition

Burst

Length

Starting Column

Address

Order of Access Within a Burst

Sequential

Interleaved

A2

A1

A0

2

00-1

0-1

11-0

1-0

Note :

1. For full-page accesses: y = 512

2. For a burst length of two, A1-A8 select the block-

of-two burst; A0 selects the starting column within the

4

0

0

0-1-2-3

0-1-2-3

0

1

1-2-3-0

1-0-3-2

1

0

2-3-0-1

2-3-0-1

11

3-0-1-2

3-2-1-0

00

0

0-1-2-3-4-5-6-7

0-1-2-3-4-5-6-7

00

1

1-2-3-4-5-6-7-0

1-0-3-2-5-4-7-6

0

1

0

2-3-4-5-6-7-0-1

2-3-0-1-6-7-4-5

block.

3. For a burst length of four, A2-A8 select the block-

of-four burst; A0-A1 select the starting column within

the block.

4. For a burst length of eight, A3-A8 select the

block-of-eight burst; A0-A2 select the starting column

within the block.

5. For a full-page burst, the full row is selected and A0-A8

8

0

1

0

2 3 4 5 6 7 0 1

2 3 0 1 6 7 4 5

01

1

3-4-5-6-7-0-1-2

3-2-1-0-7-6-5-4

10

0

4-5-6-7-0-1-2-3

4-5-6-7-0-1-2-3

10

1

5-6-7-0-1-2-3-4

5-4-7-6-1-0-3-2

11

0

6-7-0-1-2-3-4-5

6-7-4-5-2-3-0-1

11

1

7-0-1-2-3-4-5-6

7-6-5-4-3-2-1-0

Full

n=A0 8

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.

6

Rev. A | July 2010

Full

Page

n=A0-8

(Location 0-511)

Not Supported