Texas Instruments TMS320C6455 manual Sequence. Values 4-7 are reserved for this field

Models: TMS320C6455

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DDR2 Memory Controller Registerswww.ti.com

Table 20. SDRAM Configuration Register (SDCFG) Field Descriptions (continued)

Bit

Field

Value

Description

 

 

 

 

11-9

CL

 

CAS latency. The value of this field defines the CAS latency, to be used when accessing

 

 

 

connected SDRAM devices. A write to this field will cause the DDR2 Memory Controller to

 

 

 

start the SDRAM initialization sequence. This field is writeable only when the TIMUNLOCK bit

 

 

 

is unlocked. Values 0, 1, 6, and 7 are reserved for this field.

 

 

2

CAS latency of 2.

 

 

3

CAS latency of 3.

 

 

4

CAS latency of 4.

 

 

5

CAS latency of 5.

 

 

 

 

8-7

Reserved

 

Reserved. The reserved bit location is always read as 0. A value written to this field has no

 

 

 

effect.

 

 

 

 

6-4

IBANK

 

Internal SDRAM bank setup bits. Defines number of banks inside connected SDRAM devices.

 

 

 

A write to this bit will cause the DDR2 Memory Controller to start the SDRAM initialization

 

 

 

sequence. Values 4-7 are reserved for this field.

 

 

0

One bank SDRAM devices.

 

 

1

Two banks SDRAM devices.

 

 

2

Four banks SDRAM devices.

 

 

3

Eight banks SDRAM devices.

 

 

 

 

3

Reserved

 

Reserved. The reserved bit location is always read as 0. A value written to this field has no

 

 

 

effect.

 

 

 

 

2-0

PAGESIZE

 

Page size bits. Defines the internal page size of the external DDR2 memory. A write to this bit

 

 

 

will cause the DDR2 Memory Controller to start the SDRAM initialization sequence. Values 4-7

 

 

 

are reserved for this field.

 

 

0

256-word page requiring 8 column address bits.

 

 

1

512-word page requiring 9 column address bits.

 

 

2

1024-word page requiring 10 column address bits.

 

 

3

2048-word page requiring 11 column address bits.

 

 

 

 

42

C6455/C6454 DDR2 Memory Controller

SPRU970G December 2005 Revised June 2011

 

 

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Texas Instruments TMS320C6455 manual Sequence. Values 4-7 are reserved for this field