Staticmemory write enable delay 0-3 registers, Staticmemory write enable delay 0–3 registers – Digi NS9215 User Manual

Page 254

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M E M O R Y C O N T R O L L E R

StaticMemory Write Enable Delay 0–3 registers

254

Hardware Reference NS9215

Note:

Synchronous burst mode memory devices are not supported.

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

S t a t i c M e m o r y W r i t e E n a b l e D e l a y 0 – 3 r e g i s t e r s

Address: A070 0204 / 0224 / 0244 / 0264

The Static Memory Write Enable Delay 0–3 registers allow you to program the delay
from the chip select to the write enable assertion. The Static Memory Write Enable
Delay register is used in conjunction with the Static Memory Write Delay registers,
to control the width of the write enable signals. It is recommended that these
registers be modified during system initialization, or when there are no current or
outstanding transactions. Wait until the memory controller is idle, then enter low-
power or disabled mode.

Register

D02

R/W

BMODE

Burst mode
Allows the static output enable signal to toggle during bursts.
0

Do not toggle output enable during bursts

1

Toggle output enable during bursts

D01:00

R/W

MW

Memory width

00

8 bit (reset value for chip select 0, 2, and 3 on

reset_n

)

01

16 bit

10

32 bit

11

Reserved

The value of the chip select 1 memory width field on power-on
reset (

reset_n

) is determined by the

gpio_a[0], addr[23]

signal. This

value can be overridden by software.

Note:

For chip select 1, the value of the

gpio_a[0], addr[23]

signal

is reflected in this field. When programmed, this register
reflects the last value written into it.

Bits

Access

Mnemonic

Description

13

12

11

10

9

8

7

6

5

4

3

2

1

0

15

14

31

29

28

27

26

25

24

23

22

21

20

19

18

17

16

30

Reserved

Reserved

WWEN

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