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Texas Instruments TMS320C6457 manual HPI Operation, Host Port Interface HPI

Models: TMS320C6457

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HPI Operation

Figure 10. 16-Bit Multiplexed Mode Host Write Cycle With HAS Tied High

HCS

Internal

HSTRB

HR/W

HCNTL[1:0]

HD[15:0]

Data 1

Data 2

HRDYA

HHWIL

HPI latches		HPI latches
control information	control information
	HPI latches	HPI latches
	data	data

ADepending on the type of write operation (HPID without autoincrementing, HPIA, HPIC, or HPID with autoincrementing) and the state of the FIFO, transitions on HRDY may or may not occur. For more information, see Section 3.9.

SPRUGK7A –March 2009 –Revised July 2010

Host Port Interface (HPI)

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Texas Instruments TMS320C6457 manual HPI Operation, Host Port Interface HPI

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 Registers1.2 Summary of the HPI Signals Table 2. HPI SignalsTable 1. Summary of HPI Registers continued Table 2. HPI SignalsIntroduction to the HPI Host Port Interface HPI2 Using the Address Registers 2.1 Single-HPIA Mode2.2 Dual-HPIA Mode 3.1 Host-HPI Signal Connections in the 32-Bit Multiplexed Mode3 HPI Operation in the 16-Bit Multiplexed Mode in the 32-Bit Multiplexed ModeMultiplexed Mode 3.2 HPI Configuration and Data FlowTable 3. Options for Connecting Host and HPI Data Strobe Pins 3.3 HDS2, HDS1, and HCS Data Strobing and Chip SelectionFigure 6. HPI Strobe and Select Logic Table 4. Access Types Selectable by the HCNTL Signals Table 5. Cycle Types Selectable With the HCNTL and HR/W Signals3.4 HCNTL10 and HR/W Indicating the Cycle Type 3.6 HAS Forcing the HPI to Latch Control Information Early Figure 7. 16-Bit Multiplexed Mode Host Read Cycle Using HAS HPI OperationHost Port Interface HPI Figure 8. 16-Bit Multiplexed Mode Host Write Cycle Using HAS HPI OperationHost 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 Mode3.9.1 HRDY Behavior During 16-Bit Multiplexed Read Operations Case 1 HPIA Write Cycle Followed by Nonautoincrement HPID Read CycleCase 2 HPIA Write Cycle Followed by Autoincrement HPID Read Cycles 3.9.2 HRDY Behavior During 16-Bit Multiplexed Write Operations Case 1 No AutoincrementingCase 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 operationFigure 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 accesses Case 2 Autoincrementing Selected, FIFO Empty Before WriteCase 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 FIFOs and Bursting 6.1 Read 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