8 issue a pall command, Issue a pall command -30, Table 18-21 – Freescale Semiconductor MCF5480 User Manual

Page 478

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MCF548x Reference Manual, Rev. 3

18-30

Freescale Semiconductor

18.8.8

Issue a PALL command

The SDCR should be programmed as shown in

Figure 18-21

. This will issue a second PALL command to

the memory. The same SDCR value calculated in

Section 18.8.5, “SDRAM Control Register Settings and

PALL command

” is used (0xE10D_0002).

This configuration results in a value of SDCR = 0xE10D_0002, as described in

Table 18-22

.

Table 18-21. SDMR Field Descriptions

Bits

Name

Setting

Description

31–30

BNKAD

00

00 selects the mode register.

29–25

OP_MODE

0010

Selects normal operating mode and resets the DLL.

24–22

CASL

010

CAS latency of two clocks.

21

BT

0

Sequential burst type.

20–18

BLEN

011

Burst length of eight

17

0

Reserved. Should be cleared.

16

CMD

1

Initiate the LMR command.

15–0

0

Reserved. Should be cleared.

31

30

29

28

27

26

25

24

23

22

21

20

19

18

17

16

Field MODE

_EN

CKE

DDR

REF

MUX

AP

DRIV

E

RCNT

Setting

1110_0001_0000_1101

(hex)

E

1

0

D

15

14

13

12

11

10

9

8

7

6

5

4

3

2

1

0

Field

DQS_OE

BUFF

IREF IPALL

Setting

0000_0000_0000_0010

(hex)

0

0

0

2

Figure 18-21. SDRAM Control Register Settings + MODE_EN and IPALL

Table 18-22. SDCR + MODE_EN and IPALL Field Descriptions

Bits

Name

Setting

Description

31

MODE_EN

1

Mode register is writable.

30

CKE

1

SDCKE is asserted

29

DDR

1

DDR mode is enabled

28

REF

0

Automatic refresh is disabled

27–26

00

Reserved. Should be cleared.

25–24

MUX

01

01 is the MUX setting for a 13 x 9 x 4 memory. See

Table 18-2

.

23

AP

0

0 sets the auto precharge control bit to A10.

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