Sdramdevcfg[3:0, He sdramdevcfg[3:0] r, Sdramdevcfg[3:0] speci – Cirrus Logic EP93xx User Manual

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DS785UM1

Copyright 2007 Cirrus Logic

SDRAM, SyncROM, and SyncFLASH Controller
EP93xx User’s Guide

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Latched nCS[7:6] pins values:

Asynchronous (ASDO = ‘0’)

11 - 32-bit
10 - 32-bit
01 - 16-bit
00 - 8-bit

Synchronous (ASDO = ‘1’)

11 - 32-bit SROM (RAS=2, CAS=5, BL=4)
10 - 32-bit SFLASH (WBM=1, CAS=3, BL=4)
01 - 16-bit SROM (RAS=2, CAS=5, BL=8)
00 - 16-bit SFLASH (WBM=1, CAS=3, BL=4)

Note: 8-bit wide bus is not supported for SyncROM or SyncFLASH.

If booting from Asynchronous ROM, asynchronous memory bank zero (nCS0) is mapped to
address 0x0000_0000. If booting from SyncROM or SyncFLASH, Synchronous Memory
Domain 3 (nSDCS3) is re-mapped to address 0x0000_0000. This re-mapping of nSDCS3
does not change until after the boot process is completed and the processor is reset (not
power-on reset). At that time, nSDCS3 is mapped back to address 0xF000_0000, the
beginning address of Synchronous Memory Domain 3.

SDRAMDevCfg[3:0]

Address:

SDRAMDevCfg0: 0x8006_0010 - Read/Write
SDRAMDevCfg1: 0x8006_0014 - Read/Write
SDRAMDevCfg2: 0x8006_0018 - Read/Write
SDRAMDevCfg3: 0x8006_001C - Read/Write

Default:

0x0122_0008

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RSVD

Auto

Precharge

RSVD

RasToCas

WBM

CasLat

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14

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11

10

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8

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5

4

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2

1

0

RSVD

SFConfig

Addr

2K

PAGE

SROMLL

SROM512

Bank

Count

External

Bus

Width

RSVD

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