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Texas Instruments TMS320C6457 manual Case 3 Autoincrementing Selected, FIFO Not Empty Before Write

Models: TMS320C6457

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(Case 3: Autoincrementing Selected, FIFO Not Empty Before Write)

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HPI Operation

Figure 18. HRDY Behavior During a Data Write Operation in the 16-Bit Multiplexed Mode

(Case 3: Autoincrementing Selected, FIFO Not Empty Before Write)

HPIA write

HCS

HPID+ writes

HCNTL[1:0] 10 10 01 01 01 HR/W

HHWIL Internal

HSTRB

1st halfword

2nd halfword

1st halfword

2nd halfword

1st halfword

HD[15:0]

HRDY

3.9.3HRDY Behavior During 32-Bit Multiplexed Read Operations

Figure 19 shows an HPIC (HCNTL[1:0] = 00b) read or an HPIA (HCNTL[1:0] = 10b) read access for 32-bit multiplexed HPI operation. Note that neither an HPIC nor an HPIA read access causes HRDY to become active.

Figure 19. HRDY Behavior During an HPIC or HPIA Read Cycle in the 32-Bit Multiplexed Mode

HCS

HCNTL[1:0]

00 or 10

HR/W

Internal

HSTRB

HD[31:0]

HRDY

Figure 20 shows an HPIA (HCNTL[1:0] = 10b) write access followed by an HPID (HCNTL[1:0] = 11b) read access for 32-bit multiplexed HPI operation.

SPRUGK7A –March 2009 –Revised July 2010

Host Port Interface (HPI)

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Copyright © 2009–2010, Texas Instruments Incorporated

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Texas Instruments TMS320C6457 manual Case 3 Autoincrementing Selected, FIFO Not Empty Before Write

Contents

TMS320C6457 DSP Host Port Interface HPI Users GuideCopyright 2009-2010, Texas Instruments Incorporated SPRUGK7A -March 2009 -Revised JulyIntroduction to the HPI List of Figures List of FiguresList of Tables Preface Read This FirstAbout This Manual Notational ConventionsUsers Guide Host Port Interface HPI1 Introduction to the HPI Figure 1. HPI Position in the Host-DSP SystemIntroduction to the HPI 1.1 Summary of the HPI RegistersTable 2. HPI Signals 1.2 Summary of the HPI SignalsTable 1. Summary of HPI Registers continued Table 2. HPI SignalsIntroduction to the HPI Host Port Interface HPI2.1 Single-HPIA Mode 2 Using the Address Registers2.2 Dual-HPIA Mode in the 32-Bit Multiplexed Mode 3.1 Host-HPI Signal Connections3 HPI Operation in the 16-Bit Multiplexed Mode in the 32-Bit Multiplexed ModeMultiplexed Mode 3.2 HPI Configuration and Data Flow3.3 HDS2, HDS1, and HCS Data Strobing and Chip Selection Table 3. Options for Connecting Host and HPI Data Strobe PinsFigure 6. HPI Strobe and Select Logic Table 5. Cycle Types Selectable With the HCNTL and HR/W Signals Table 4. Access Types Selectable by the HCNTL Signals3.4 HCNTL10 and HR/W Indicating the Cycle Type 3.6 HAS Forcing the HPI to Latch Control Information Early HPI Operation Figure 7. 16-Bit Multiplexed Mode Host Read Cycle Using HASHost Port Interface HPI HPI Operation Figure 8. 16-Bit Multiplexed Mode Host Write Cycle Using HASHost Port Interface HPI Figure 9. 16-Bit Multiplexed Mode Host Read Cycle With HAS Tied High 3.7 Performing a Multiplexed Access Without HASHost Port Interface HPI HPI Operation3.9 Hardware Handshaking Using the HPI-Ready HRDY Signal 3.8 Single-Halfword HPIC Cycle in the 16-Bit Multiplexed ModeCase 1 HPIA Write Cycle Followed by Nonautoincrement HPID Read Cycle 3.9.1 HRDY Behavior During 16-Bit Multiplexed Read OperationsCase 2 HPIA Write Cycle Followed by Autoincrement HPID Read Cycles Case 1 No Autoincrementing 3.9.2 HRDY Behavior During 16-Bit Multiplexed Write OperationsCase 2 Autoincrementing Selected, FIFO Empty Before Write 3.9.3 HRDY Behavior During 32-Bit Multiplexed Read Operations Case 3 Autoincrementing Selected, FIFO Not Empty Before WriteCase 1 HPIA Write Cycle Followed by Nonautoincrement HPID Read Cycle Figure 21 shows an HPIA HCNTL10 = 10b write access followed by several autoincrement HPID HCNTL10 = 01b read accesses. Note that HRDY is active for the HPIA access. HRDY is also active for the first HPID read access, but not for subsequent read accessesCase 2 HPIA Write Cycle Followed by Autoincrement HPID Read Cycles 3.9.4 HRDY Behavior During 32-Bit Multiplexed Write OperationsCase 1 No Autoincrementing Figure 23 shows an HPIA HCNTL10 = 10b write access followed by an HPID HCNTL10 = 11b write access for 32-bit multiplexed HPI operationCase 2 Autoincrementing Selected, FIFO Empty Before Write Figure 25 shows an HPIA HCNTL10 = 10b write access when the write FIFO is not empty, followed by several autoincrementing HPID HCNTL10 = 01b write accesses. Note that HRDY is active twice for the HPIA access. This occurs because the FIFO is not empty and the data in the FIFO must first be written to memory. This results in an HRDY assertion immediately after the falling edge of the datastrobe HSTRB. When a write request to memory has been made that will empty the internal FIFO, the HPIA write operation can complete with the rising edge of HSTRB. The second HRDY assertion is for the write to the HPIA register. HRDY is not active for the HPID accessesCase 3 Autoincrementing Selected, FIFO Not Empty Before Write 4.1 Polling the HRDY Bit 4 Software Handshaking Using the HPI Ready HRDY Bit5 Interrupts Between the Host and the CPU Figure 26. Host-to-CPU Interrupt State Diagram5.1 DSPINT Bit Host-to-CPU Interrupts 5.2 HINT Bit CPU-to-Host InterruptsNo interrupt interrupt cleared HINT bit=0 HINT signal is high Figure 27. CPU-to-Host Interrupt State DiagramInterrupt active HINT bit=1 HINT signal is low CPU writes 0 to HINT bit6.1 Read Bursting 6 FIFOs and BurstingFigure 28. FIFOs in the HPI 6.2 Write Bursting 6.3 FIFO Flush Conditions 6.4 FIFO Behavior When a Hardware Reset or Software Reset Occurs7.2 Software Reset Considerations 7 Emulation and Reset Considerations7.3 Hardware Reset Considerations 7.1 Emulation Modes8.1 Introduction 8 HPI RegistersTable 6. Host Port Interface HPI Registers HPI RegistersFigure 29. Power and Emulation Management Register PWREMUMGMT 8.2 Power and Emulation Management Register PWREMUMGMTHPI Registers Host Port Interface HPIFigure 31. CPU Access Permissions Figure 30. Host Access Permissions8.3 Host Port Interface Control Register HPIC Table 8. Host Port Interface Control Register HPIC Field DescriptionsValue FieldDescription For host write cycle31-0 ADDRESS R-0 LEGEND R = Read only -n = value after reset LEGEND R = Read only W = Write -n = value after reset8.4 Host Port Interface Address Registers HPIAW and HPIAR 31-0 ADDRESS R/W-0Table 10. Data Register HPID Field Descriptions 8.5 Data Register HPIDTable 11. TMS320C6457 HPI Revision History Appendix A Revision HistoryModified table Revision HistoryIMPORTANT NOTICE power.ti.comamplifier.ti.com dataconverter.ti.com