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Samsung S3C2440A User Manual

Page 184

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S3C2440A RISC MICROPROCESSOR

MEMORY CONTROLLER

DEC.13, 2002

5-19

SDRAM MODE REGISTER SET REGISTER (MRSR)

Register Address

R/W

Description

Reset

Value

MRSRB6

0x4800002C

R/W

Mode register set register bank6

xxx

MRSRB7

0x48000030

R/W

Mode register set register bank7

xxx

MRSR Bit

Description

Initial

State

Reserved [11:10]

Not

used

-

WBL

[9]

Write burst length
0: Burst (Fixed)
1: Reserved

x

TM [8:7]

Test

mode

00: Mode register set (Fixed)
01, 10 and 11: Reserved

xx

CL [6:4]

CAS

latency

000 = 1 clock, 010 = 2 clocks, 011=3 clocks
Others: reserved

xxx

BT [3]

Burst

type

0: Sequential (Fixed)
1: Reserved

x

BL [2:0]

Burst

length

000: 1 (Fixed)
Others: Reserved

xxx

Note:

MRSR register must not be reconfigured while the code is running on SDRAM.

IMPORTANT NOTE: IN SLEEP MODE, SDRAM HAS TO ENTER SDRAM SELF-REFRESH MODE.