Digi NS9215 manual Dal, Data-in to active command tDAL or tAPW

Models: NS9215

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

Dynamic Memory Write Recovery Time register

Register bit

assignment

Bits

Access

Mnemonic

Description

 

 

 

 

 

 

D31:04

N/A

Reserved

N/A (do not modify)

 

 

 

 

 

 

D03:00

R/W

DAL

Data-in to active command (tDAL or tAPW)

 

 

 

 

0x0–0xE

 

 

 

 

n+1 clock cycles, where the delay is in clk_out cycles.

0xF

15 clock cycles (reset value on reset_n)

D y n a m i c M e m o r y W r i t e R e c o v e r y T i m e r e g i s t e r

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

Address: A070 0044

The Dynamic Memory Write Recovery Time register allows you to program the write recovery time, tWR. It is recommended that this register 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. This value normally is found in SDRAM datasheets as tWR, tDPL, tRWL, or tRDL.

Note: The Dynamic Memory Write Recovery Time register is used for all four dynamic memory chip selects. The worst case value for all chip selects must be programmed.

Register

31

30

29

28

27

26

25

24

23

22

21

20

19

18

17

16

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Reserved

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

15

14

13

12

11

10

9

8

7

6

5

4

3

2

1

0

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Reserved

 

 

 

 

 

 

 

WR

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Register bit

assignment

Bits

Access

Mnemonic

Description

 

 

 

 

 

 

D31:04

N/A

Reserved

N/A (do not modify)

 

 

 

 

 

 

D03:00

R/W

WR

Write recovery time (tWR, tDPL, tRWL, or tRDL)

 

 

 

 

0x0–0xE

 

 

 

 

n+1 clock cycles, where the delay is in clk_out cycles.

0xF

16 clock cycles (reset value on reset_n)

242Hardware Reference NS9215

Page 242
Image 242
Digi NS9215 manual Dal, Data-in to active command tDAL or tAPW