User’s Manual

3.5.3.1 DRAM Clock/Drive Control

This section can set the DRAM clock/driver timing.

 

Item

 

Options

 

 

Description

 

 

 

 

By SPD

 

 

 

 

 

 

 

100NHz

Set the

memory bus frequency

to operate at

 

DRAM Clock

 

133 MHz

 

 

various

values for the proper

memory clock

 

 

166 MHz

 

 

 

setting

 

 

 

 

 

200 MHz

 

 

 

 

 

 

 

 

 

 

 

266 MHz

 

 

 

 

 

 

Manual

 

 

 

 

DRAM Timing

 

Auto By SPD

Set the memory timings for the said timings or

 

 

Turbo

DRAM Cycle Lengths of 2 or 2.5.

 

 

 

 

 

 

 

 

Ultra

 

 

 

 

 

1.5 / 2

 

This controls the time dealy passing before the

 

SDRAM CAS Latency

2 / 3

 

 

 

SDRAM starts to carry out a read command after

 

(DDR/DDR2)

2.5 / 4

 

 

 

receiving it.

 

 

 

3 / 5

 

 

 

 

 

 

 

 

 

 

 

Diabled

Enables to set the interleave mode of the SDRM

 

 

 

2 Bank

 

Bank Interleave

 

interface

which allows banks of SDRAM to

 

 

4 Bank

 

 

 

alternate their refresh and access cycles.

 

 

 

8 Bank

 

 

 

 

 

 

 

 

 

2T

This item sets the length of time taking to

 

 

 

precharge a row in the memory module before

 

Precharge to Active(Trp)

 

3T

a row being active and appears only when

 

 

4T

DRAM timing is set at Manual. Longer values

 

 

 

 

 

 

5T

are safer but probably not acting the best

 

 

 

 

 

performance.

 

 

 

 

5T, 6T, 7T, 8T

This item sets the length of time that a row

 

 

 

staying active fore precharging and appears only

 

Active to Precharge(Tras)

 

9T, 10T, 11T, 12T

 

 

when DRAM timing is set at Manual. Longer

 

 

13T, 14T, 15T, 16T

 

 

 

17T, 18T, 19T, 20T

values are safer but probably not acting the best

 

 

 

 

 

performance.

 

 

 

 

8T, 9T, 10T, 11T,

This timing controls the length of the delay

 

 

 

12T, 13T, 14T, 15T,

 

Active to CMD(Trcd)

 

16T, 17T, 18T, 19T,

between when a memory bank is activated to

 

 

 

20T, 21T, 22T, 23T,

when a read/write command is sent to that bank.

 

 

 

24T, 25T, 26T

 

 

 

 

 

 

12T

Set the REF to ACT/REF to REF timing.

 

 

 

13T

REF to ACT/REF to REF(Trfc)

 

This field appears when DRAM Timing is set at

 

14T

 

 

 

Manual.

 

 

 

 

 

15T

 

 

 

 

 

 

 

 

 

 

 

2T

Set the minimum time interval between

 

ACT(0) to ACT(1) (TRRD)

 

3T

successive ACTIVE commands to the different

 

 

4T

banks. This field appears when DRAM Timing is

 

 

 

 

 

 

5T

set at Manual.

 

 

Read to Precharge (Trtp)

 

2T

Use this option to select Read

to Precharge

 

 

3T

(Trtp) to set the timing by dram SPD.

 

 

 

 

Write to Read CMD (Twtr)

 

2T / 3T

Use this option to select Write to Read CMD

 

 

1T / 2T

(Twtr) to set the timing by dram SPD.

 

 

 

 

 

 

2T

 

 

 

 

Write Recovery Time (Twr)

 

3T

Use this option to select Write Recovery Time

 

 

4T

(Twr) to set the timing by dram SPD.

 

 

 

 

 

 

5T

 

 

 

 

DRAM Command Rate

 

2T Command

Allows to set the DRAM Command Rate.

 

 

1T Command

 

 

 

 

 

 

 

RDSAIT mode

 

Manual

 

 

 

 

 

Auto

 

 

 

 

 

 

 

 

 

 

RDSAIT selection

3

 

Key in a HEX number (Min = 0000, Max = 003F)

ECM-3711 Series User’s Manual 61