Table 6-18 – Intel PXA26X User Manual

Page 229

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Intel® PXA26x Processor Family Developer’s Manual

6-39

Memory Controller

Table 6-19

shows sample frequency configurations for programming non-SDRAM timing fast

flash. When in doubt, the higher frequency configuration and corresponding CAS latency must be
used.

Table 6-18. Read Configuration Register Programming Values

Bits

Field Name

Value to Program

2:0

BURST LENGTH

010

8 Word Burst

5:3

RESERVED

000

6

CLOCK CONFIGURATION

1

Use rising edge of clock

7

BURST SEQUENCE

1

Linear burst Order

(INTEL BURST ORDER IS NOT SUPPORTED)

8

WAIT CONFIGURATION

N/A

nWAIT from the flash device is ignored by the
processor.

9

DATA OUTPUT CONFIGURATION

0

Hold data for one clock

10

RESERVED

0

13:11

FREQUENCY CONFIGURATION

010 – CAS Latency 3

011 – CAS Latency 4

100 – CAS Latency 5

101 – CAS Latency 6

110 – CAS Latency 7

Chosen based on the AC Characteristics – Read only
Operation section of the flash device data sheet

14

RESERVED

0

15

READ MODE

0 – Synchronous Operation

1 – Asynchronous Operation

Table 6-19. Frequency Code Configuration Values Based on Clock Speed (Sheet 1 of 2)

MEMCLK

Frequency

SDCLK0

Frequency

MDREFR:

K0DB2

Valid

Frequency

Configurations

Corresponding

CAS Latencies

20

20

0

2 / 3 / 4 / 5 / 6

3 / 4 / 5 / 6 / 7

33

33

0

3 / 4 / 5 / 6

4 / 5 / 6 / 7

50

50

0

4 / 5 / 6

5 / 6 / 7

25

1

2 / 3 / 4 / 5 / 6

3 / 4 / 5 / 6 / 7

66

66

0

5 / 6

6 / 7

33

1

3 / 4 / 5 / 6

4 / 5 / 6 / 7

100

50

1

4 / 5 / 6

5 / 6 / 7

118

59

1

5 / 6

6 / 7

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