Texas Instruments TMS320DM644x manual Fifo Operation During Card Read Diagram

Page 20

www.ti.com

Peripheral Architecture

Figure 10. FIFO Operation During Card Read Diagram

 

FIFO Check1/Start

 

 

Yes

FIFO

 

 

 

full

 

 

 

?

 

 

 

No

 

 

 

Capture data,

 

 

 

no DMA pending

 

 

 

Increment counter

 

 

No

Counter

 

 

 

=FIFOLEV

 

 

 

?

 

 

 

Yes

 

 

 

Generate DMA

 

 

 

Reset counter

 

 

 

FIFO check 2

 

 

Yes

FIFO

 

 

 

full

 

 

 

?

 

 

 

No

 

 

 

Capture data,

 

 

 

DMA

 

 

 

Increment counter

 

Idle, DMA pending

 

Counter

Yes

 

 

=FIFOLEV

No

DMA

 

?

 

done

 

 

 

?

 

No

 

 

 

 

 

Yes

No

DMA

 

Generate DMA

 

done

 

 

 

?

 

Reset counter

 

 

 

 

Yes

 

 

20

Multimedia Card (MMC)/Secure Digital (SD) Card Controller

SPRUE30B –September 2006

Image 20
Contents Users Guide Submit Documentation Feedback Contents Appendix a List of Figures List of Tables Read This First Trademarks Purpose of the Peripheral FeaturesFunctional Block Diagram Supported Use Case Statement Industry Standards Compliance StatementMMC/SD Controller Interface Diagram MMC/SD Controller Clocking Diagram Clock ControlSignal Descriptions MMC/SD Controller Pins Used in Each Mode1 MMC/SD Mode Write Sequence Protocol DescriptionsPortion Sequence Description MMC/SD Mode Write Sequence2 MMC/SD Mode Read Sequence MMC/SD Mode Read Sequence Data Flow in the Input/Output FifoCRC RD CMDFifo Operation Diagram Data Flow in the Data Registers Mmcdrr and Mmcdxr 1st 2nd 3rd 4th Mmcdrr or Mmcdxr registers Support byten =1st 2nd 3rd 4th Support byten = 1111 1110 CPU Reads Fifo Operation During Card Read OperationEdma Reads Fifo Operation During Card Read Diagram CPU Writes Fifo Operation During Card Write OperationEdma Writes Fifo Operation During Card Write Diagram Reset Considerations InitializationInitializing the Clock Controller Registers Mmcclk Initialize the Interrupt Mask Register MmcimInitialize the Time-Out Registers Mmctor and Mmctod Initialize the Data Block Registers Mmcblen and MmcnblkMonitoring Activity in the MMC/SD Mode Determining Whether New Data is Available in MmcdrrChecking For a Data Transmit Empty Condition Interrupt Support Interrupt Events and RequestsInterrupt Multiplexing Description of MMC/SD Interrupt RequestsEmulation Considerations Power ManagementDMA Event Support MMC Card Identification Procedure Card Identification OperationProcedures for Common Operations SD Card Identification Procedure MMC/SD Mode Single-Block Write Operation Using CPU MMC/SD Mode Single-Block Write Operation MMC/SD Mode Single-Block Write Operation Using the Edma MMC/SD Mode Single-Block Read Operation Using the CPUMMC/SD Mode Single-Block Read Operation Using Edma MMC/SD Mode Single-Block Read OperationMMC/SD Mode Multiple-Block Write Operation Using CPU MMC/SD Multiple-Block Write Operation MMC/SD Mode Multiple-Block Write Operation Using Edma MMC/SD Mode Multiple-Block Read Operation Using CPUMMC/SD Mode Multiple-Block Read Operation Using Edma MMC/SD Mode Multiple-Block Read OperationOffset Acronym Register Description Bit Field Value Description MMC Control Register MmcctlMMC Control Register Mmcctl Field Descriptions MMC Memory Clock Control Register Mmcclk MMC Memory Clock Control Register Mmcclk Field DescriptionsClken Clkrt ClkenBit Field MMC Status Register 0 MMCST0MMC Status Register 0 MMCST0 Field Descriptions Write-data CRC error MMC Status Register 1 MMCST1 MMC Status Register 1 MMCST1 Field DescriptionsFifoful Fifoemp DAT3ST Drful Dxemp Clkstp Busy FifofulMMC Interrupt Mask Register Mmcim MMC Interrupt Mask Register Mmcim Field DescriptionsEtrndne Edated Edrrdy Edxrdy EtrndneTOR MMC Response Time-Out Register MmctorMMC Response Time-Out Register Mmctor Field Descriptions MMC Data Read Time-Out Register Mmctod MMC Data Read Time-Out Register Mmctod Field DescriptionsBlen MMC Block Length Register MmcblenMMC Block Length Register Mmcblen Field Descriptions MMC Number of Blocks Register Mmcnblk MMC Number of Blocks Counter Register MmcnblcMMC Number of Blocks Register Mmcnblk Field Descriptions NblkMMC Data Receive Register Mmcdrr MMC Data Transmit Register MmcdxrMMC Data Receive Register Mmcdrr Field Descriptions MMC Data Transmit Register Mmcdxr Field DescriptionsMMC Command Register Mmccmd MMC Command Register Mmccmd Field DescriptionsDmatrig Dclr Initck Wdatx Strmtp Dtrw Rspfmt Bsyexp PplenCRC7 Stream enableBit Position Command Register Description MMC Argument Register Mmcarghl MMC Argument Register Mmcarghl Field DescriptionsArgh ArglMMC Response Registers MMCRSP0-MMCRSP7 R1, R3, R4, R5, or R6 Response 48 Bits R2 Response 136 BitsBit Position of Response Register MMCRSP4-0MMC Command Index Register Mmccidx MMC Command Index Register Mmccidx Field DescriptionsMMC Data Response Register Mmcdrsp MMC Data Response Register Mmcdrsp Field DescriptionsMMC Fifo Control Register Mmcfifoctl MMC Fifo Control Register Mmcfifoctl Field DescriptionsAccwd Fifolev Fifodir Fiforst AccwdTable A-1. Document Revision History Reference Additions/Modifications/DeletionsAppendix a Important Notice