Table, Refrshtimr, 0 - see – Cirrus Logic EP93xx User Manual

Page 516: Table 13-14, 1 - see

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13-20

DS785UM1

Copyright 2007 Cirrus Logic

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

1

3

1

3

13

Writing a ‘1’ to this bit, in combination with the values of
the MRS and LCR bits, cause the Synchronous Memory
controller to issue either NOP or PreALL accesses to
SDRAM devices as shown in

Table 13-4

.

0 - See

Table 13-14

1 - See

Table 13-14

RefrshTimr

Address: 0x8006_0008 - Read/Write

Default: 0x0000_0080

Table 13-14. Synchronous Memory Command Encoding

Initialize

MRS

LCR

Synchronous Memory Command

1

1

0

Issue NOP to Synchronous Memory

1

0

0

Issue PreALL (Pre-charge All) to SDRAM

0

1

0

Enable access to Synchronous Memory device mode register

0

1

1

Issue command to Synchronous FLASH Memory devices

0

0

1

UNDEFINED. Do not use.

1

0

1

UNDEFINED. Do not use.

1

1

1

UNDEFINED. Do not use.

0

0

0

Normal operation

31

30

29

28

27

26

25

24

23

22

21

20

19

18

17

16

RSVD

15

14

13

12

11

10

9

8

7

6

5

4

3

2

1

0

Refcnt

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