9 registers, 9 registers -17, Table 13-12. address bits used for chip select -17 – Cirrus Logic EP93xx User Manual

Page 513

Advertising
background image

DS785UM1

13-17

Copyright 2007 Cirrus Logic

SDRAM, SyncROM, and SyncFLASH Controller

EP93xx User’s Guide

1

3

1

3

13

13.9 Registers

The Synchronous Memory controller has seven registers as shown in

Table 13-13

. The

Configuration registers allow software to specify the operating parameters of the
Synchronous Memory controller according to the memory device types being used. The
Refresh Timer register allows software to specify the time period between successive
synchronous memory refresh commands. The Boot Status allows software to determine the
state of the boot configuration pins.

Table 13-12. Address Bits Used for Chip Select

Boot Option

(ASDO)

A31 A30

A29

A28 Chip

select

1 0

0 0 0

nSDCS3

0 1

1 1 1

nSDCS3

X 1

1 1 0

nSDCS2

X 1

1 0 1

nSDCS1

X 1

1 0 0

nSDCS0

Table 13-13. Synchronous Memory Controller Registers

Address

Name

Description

0x8006_0000

Reserved

0x8006_0004

"GlConfig"

Global Configuration

0x8006_0008

"RefrshTimr"

Refresh Timer

0x8006_000C

"BootSts"

Boot Configuration Pins Status

"SDRAMDevCfg[3:0]"

(See Below)

0x8006_0010

SDRAMDevCfg[3:0]

Synchronous Device Configuration 0

0x8006_0014

SDRAMDevCfg[3:0]

Synchronous Device Configuration 1

0x8006_0018

SDRAMDevCfg[3:0]

Synchronous Device Configuration 2

0x8006_001C

SDRAMDevCfg[3:0]

Synchronous Device Configuration 3

Advertising