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

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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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Contents Users Guide Submit Documentation Feedback Contents List of Figures List of Tables Submit Documentation Feedback Read This First Read This First Features Functional Block DiagramPurpose of the Peripheral Industry Standards Compliance Statement Signal Descriptions Clock ControlMemory Map DDR2 Memory Controller Signal Descriptions Pin DescriptionCommand Function DDR2 Sdram CommandsTruth Table for DDR2 Sdram Commands Protocol DescriptionsMode Register Set MRS and Emrs DDR2 MRS and Emrs CommandRefresh Mode Refresh CommandActv Command Activation ActvDcab Command Deactivation Dcab and DeacDeac Command Read Command DDR2 Read CommandAddressable Memory Ranges Write WRT CommandMemory Width, Byte Alignment, and Endianness Address Type Generated by DDR2Bit Field Bit Value Bit Description Bank Configuration Register Fields for Address MappingAddress Mapping IbankLogical Address-to-DDR2 Sdram Address Map for 32-Bit Sdram Logical Address-to-DDR2 Sdram Address Map DDR2 Memory Controller Interface DDR2 Memory Controller Fifo DescriptionDDR2 Memory Controller Fifo Block Diagram Command Ordering and Scheduling, Advanced ConceptCommand Starvation Refresh Urgency Levels Refresh SchedulingPossible Race Condition Urgency Level DescriptionDevice and DDR2 Memory Controller Reset Relationship Self-Refresh ModeReset Considerations DDR2 Memory Controller Reset Effect Initiated byDDR2 Sdram Extended Mode Register 1 Configuration 11.1 DDR2 Sdram Device Mode Register Configuration ValuesDDR2 Sdram Mode Register Configuration Mode Register FieldInterrupt Support 11.2 DDR2 Sdram Initialization After Reset11.3 DDR2 Sdram Initialization After Register Configuration Edma Event SupportUsing the DDR2 Memory Controller Connecting the DDR2 Memory Controller to DDR2 SdramConnecting to Two 16-Bit DDR2 Sdram Devices Connecting to a Single 16-Bit DDR2 Sdram Device Connecting to Two 8-Bit DDR2 Sdram Devices Programming the Sdram Refresh Control Register Sdrfc Programming the Sdram Configuration Register SdcfgSdcfg Configuration FieldConfiguring Sdram Timing Registers SDTIM1 and SDTIM2 DDR2 Memory Refresh SpecificationSdrfc Configuration SDTIM1 ConfigurationDDR2 Sdram Data Register Field Sheet Parameter SDTIM2 ConfigurationDmcctl Configuration Name DescriptionDDR2 Memory Controller Registers OffsetRegister Description Module ID and Revision Register Midr Module ID and Revision Register Midr Field DescriptionsBit Field Value Description DDR2 Memory Controller Status Register Dmcstat IfrdySdram Configuration Register Sdcfg Sdram Configuration Register Sdcfg Field DescriptionsSequence. Values 4-7 are reserved for this field Sdram Refresh Control Register Sdrfc Sdram Refresh Control Register Sdrfc Field DescriptionsTrfc TRP Trcd TWR Sdram Timing 1 Register SDTIM1Sdram Timing 1 Register SDTIM1 Field Descriptions Tras TRC TrrdUsing this formula Todt Txsnr Sdram Timing 2 Register SDTIM2Sdram Timing 2 Register SDTIM2 Field Descriptions Txsrd Trtp TckeBurst Priority Register Bprio Burst Priority Register Bprio Field DescriptionsPrioraise DDR2 Memory Controller Control Register Dmcctl DDR2 Memory Controller Control Register DmcctlRevision History Rfid Products ApplicationsDSP TI E2E Community Home