EM6A9320BI-3.0 参数 Datasheet PDF下载

EtronTech

Mode Register Set (MRS)

4Mx32 DDR SDRAM

EM6A9320

The mode register is divided into various fields depending on functionality.

Burst Length Field (A2, A1, A0)

•

This field specifies the data length of column access and selects the Burst Length.

Addressing Mode Select Field (A3)

•

The Addressing Mode can be Interleave Mode or Sequential Mode. Both Sequential Mode and

Interleave Mode support burst length of 2, 4 and 8. Full page burst length is only for Sequential mode.

CAS# Latency Field (A6, A5, A4)

•

This field specifies the number of clock cycles from the assertion of the Read command to the first

read data. The minimum whole value of CAS# Latency depends on the frequency of CK. The

minimum whole value satisfying the following formula must be programmed into this field.

CAS# Latency X t

CK

t

CAC

(min)

Test Mode field :A7; DLL Reset Mode field : A8

•

These two bits must be programmed to "00" in normal operation.

( BA0, BA1)

•

Mode Resistor Bitmap

BA1

0

BA0

A11

A10

A9

Mode RFU must be set to “0”

BA0

0

1

Register Mode

MRS

EMRS

A8

DLL

A8

0

1

0

A7

TM

A7

0

0

1

A6

A5

A4

CAS Latency

A3

BT

A3

0

1

A2

A1

A0

Burst Lenght

A6

0

0

1

1

A5

1

1

0

0

A4

CAS Latency

0

Reserved

1

3 clocks

0

4 clocks

1

5 clocks

All other Reserved

Burst Definition, Addressing Sequence of Sequential and Interleave Mode

Burst Length

2

4

Start Address

A2

A1

A0

X

X

0

X

X

1

X

0

0

X

0

1

X

1

0

X

1

1

0

0

0

0

0

1

0

1

0

0

1

1

1

0

0

1

0

1

1

1

0

1

1

1

Sequential

0, 1

1, 0

0, 1, 2, 3

1, 2, 3, 0

2, 3, 0, 1

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

Interleave

0, 1

1, 0

0, 1, 2, 3

1, 0, 3, 2

2, 3, 0, 1

3, 2, 1, 0

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

8

≦

Mode

Normal

Reset DLL

Test Mode

Type

Sequential

Interleave

A2

0

0

0

1

A1

0

1

1

1

A0

Burst Length

1

2

0

4

1

8

1

Full Page (Sequential)

All other Reserved

6

Rev 0.6

May. 2006