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Texas Instruments TLV1562 manual viSLAA040

Models: TLV1562

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viSLAA040

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Texas Instruments TLV1562 manual viSLAA040

Contents

Application Report JulySLAA040 TParalInteMS3rflelADConvertertotheacing20C54xDSPtheTLV1562IMPORTANT NOTICE Contents 8.5.5 Figures List of FiguresList of Tables Interfacing the TLV1562 Parallel AD-Converter to the TMS320C54x DSPviSLAA040 2 The Board Interfacing the TLV1562 Parallel ADC to the TMS320C54x DSP1 Introduction 2.1 TMS320C54x Starter Kit2.3.1 Suggestions for the ’C54x to TLV1562 Interface 2.2 TLV1562EVM2.3 ADC TLV1562 Overview 2.3.1.1 The Universal InterfaceUsing RD or the CSTART Signal to Start Conversion 2.3.2 Recyclic ArchitectureFigure 2. TLV1562 to ’C54x DSP Interface of the EVM 2.3.3 Note on the Interface, Using an External ADC Clock Drive 2.4 Onboard Components2.4.1 TLC5618A - Serial DAC 2.4.2 THS5651 - Parallel Output CommsDAC Figure 3. TLC5618A to ’C542 DSP InterfaceFigure 4. THS5651 to C542 DSP Interface 3 Operational Overview 3.1 Reference Voltage Inputs3.2 Input Data Bits Table 1. Signal Connections 3.3 Connections Between the DSP and the EVMTable 3. 2-Position Jumpers 3.3.1 Jumpers Used on the TLV1562EVMTable 2. 3-Position Jumpers Operational Overview4 The Serial DAC/DSP System Table 4. DSP/DAC InterconnectionTable 5. DSP Serial Port Signals and Registers 5 The DSP Serial Port6 Other DSP/TLV1562 Signals 6.1 DSP Internal Serial Port Operation7.1 Writing to the ADC 7.2 Mono Interrupt Driven Mode Using RD7 Conversation Between the TLV1562 and the DSP Table 6. DSP Algorithm for Writing to the ADCInterfacing the TLV1562 Parallel ADC to the TMS320C54x DSP Table 7. DSP Algorithm for Mono Interrupt Driven Mode Using RDConversation Between the TLV1562 and the DSP tDCSL-sample+1ADCSYSCLKConversation Between the TLV1562 and the DSP 7.3 Mono Interrupt Driven Mode Using CSTARTTable 8. DSP Algorithm for Mono Interrupt Driven Mode Using CSTART 14 SLAA040Conversation Between the TLV1562 and the DSP 7.4 Dual Interrupt Driven ModeTable 9. DSP Algorithm for Dual Interrupt Driven Mode Interfacing the TLV1562 Parallel ADC to the TMS320C54x DSPConversation Between the TLV1562 and the DSP 7.5 Mono Continuous ModeTable 10. DSP Algorithm for Mono Continuous Mode 16 SLAA040Conversation Between the TLV1562 and the DSP 7.6 Dual Continuous ModeTable 11. DSP Algorithm for Dual Continuous Mode Interfacing the TLV1562 Parallel ADC to the TMS320C54x DSP8 Software Overview 8.1 Software Development tools8.2 DSP Memory Map Figure 5. Memory Map Software OverviewInterfacing the TLV1562 Parallel ADC to the TMS320C54x DSP 8.3.1 Optimizing CPU Resources for Maximum Data Rates 8.3.3 Timer Output8.3 Programming Strategies for the ’C54x, Explanations 8.3.2 Address and Data Bus for I/O Tasks8.3.5 Generating the Chip Select Signal and the CSTART Signal 8.3.4 Data Page Pointer8.3.6 Interfacing the Serial DAC 5618A to the DSP GOTO MARK 8.3.7 Interrupt Latency8.3.8 Branch Optimization goto/dgoto, call/dcall MARK DP = #1 ARP = #58.3.9 Enabling Software Modules .if/.elseif/.endif 8.4 Software Code Explanation8.4.1 Software Principals of the Interface Advantage 8.4.1.2 Timed Solution8.4.1.1 Software Polling DisadvantageAdvantages 8.4.1.3 Interrupt Driven Solution8.4.1.5 Setting the Right Switches DisadvantagesTable 12. Switch Settings TaskTable 13. Instruction in the Program Header Step Table 14. Instruction in the Program Header Step 8.5 Flow Charts and Comments for All Software Modes8.5.1 The Mono Interrupt Driven Mode Using RD to Start Conversion 8.4.1.6 Common Software for all ModesCode verification Program FilesOther Files common file of all modes constants definitionFigure 6. Software Flow of the Mono Interrupt Driven Solution Software OverviewInterfacing the TLV1562 Parallel ADC to the TMS320C54x DSP Program Files 8.5.2 Mono Interrupt Driven Mode Using CSTART to Start ConversionCalibration procedure of the DAC Other FilesInitialize SPI Software OverviewInterfacing the TLV1562 Parallel ADC to the TMS320C54x DSP SAVE8.5.2.1 Throughput Optimization† This only works for one TLV1562 not multiple because CS is not usedMaximum Performance at 1.2 MSPS with Internal Clock 8.5.3 Dual Interrupt Driven ModeFigure 8. Time Optimization monocst1 Program FilesIMPORTANT NOTE The code has been optimized to maximize the data throughput. It was found that CSTART can be pulled low earlier than the data read instruction is performed by the DSP. This saves the 100-ns wait time in STEP 3 because the data read requires at least 100 ns. Therefore, CSTART gets pulled high directly after data read, and the interface becomes faster and gains throughput. This variation will be found in the code. The data acquisition is done in a small number of steps that explains everything inside the code Code verificationSoftware Overview Interfacing the TLV1562 Parallel ADC to the TMS320C54x DSPOther Files 8.5.4 Mono Continuous ModeProgram Files Code verificationFigure 10. Flow Chart Mono Continuous Mode Software OverviewInterfacing the TLV1562 Parallel ADC to the TMS320C54x DSP Other Files 8.5.5 Dual Continuous ModeProgram Files Code verificationFigure 11. Flow Chart Dual Continuous Mode Software OverviewInterfacing the TLV1562 Parallel ADC to the TMS320C54x DSP Program Files Other FilesCode verification 8.6.1.1 Constants.asm 8.6 Source Code8.6.1 Common Software for all Modes except C-Callable Software OverviewSoftware Overview set 000C0h Operate without calibrated inputs no offset42 SLAA040 8.6.1.2 Interrupt Vectors Software OverviewInterfacing the TLV1562 Parallel ADC to the TMS320C54x DSP 4C internal timer interrupt Software Overview44 SLAA040 File Linker.lnk COMMAND FILE 8.6.1.3 linker,cmd8.6.1.4 Auto.bat title ”COMMAND FILE FOR TLV1562.ASM”Software Overview Mainprogram Monomode.asmpointer address when using any of the following variables jump address to init. new channelSoftware Overview sent value to register CR0 of the ADCInterfacing the TLV1562 Parallel ADC to the TMS320C54x DSP endif if INT0DRIVENPOLLINGDRV Software Overviewif SENDOUTSERIAL 48 SLAA040Software Overview endifInterfacing the TLV1562 Parallel ADC to the TMS320C54x DSP endif if DIFFINPUTMODE if AUTOPWDNENABLESoftware Overview endifSoftware Overview elseif NOINT0SIGInterfacing the TLV1562 Parallel ADC to the TMS320C54x DSP endif 52 SLAA040Software Overview 8.6.3 Calibration of the ADCCALIBRAT.ASM Interfacing the TLV1562 Parallel ADC to the TMS320C54x DSPSoftware Overview 54 SLAA040if SMECALIBRATION Software Overviewendif Interfacing the TLV1562 Parallel ADC to the TMS320C54x DSPSoftware Overview 56 SLAA040endif Software Overviewendif Interfacing the TLV1562 Parallel ADC to the TMS320C54x DSPMainprogram Monomode.asm Software Overview58 SLAA040 Software Overview Interfacing the TLV1562 Parallel ADC to the TMS320C54x DSPSoftware Overview if SENDOUTSERIAL60 SLAA040 if INT0DRIVENPOLLINGDRV Software Overviewendif endifSoftware Overview elseif R4BITRESOLUT62 SLAA040 = bit*AR5,15-0 Software Overviewif POLLINGDRV elseif INT0DRIVENendif Software Overviewif INT0DRIVEN if SENDOUTPARALLELSoftware Overview endifInterfacing the TLV1562 Parallel ADC to the TMS320C54x DSP Interrupt Routine handler - see 8.6.1.2 Interrupt Vectors 8.6.5 Dual Interrupt Driven ModeConstants definition - see 8.6.1.1 Constants.asm Mainprogram DUALIRQ1.asmSoftware Overview Interfacing the TLV1562 Parallel ADC to the TMS320C54x DSPSoftware Overview if SENDOUTSERIALSoftware Overview endifInterfacing the TLV1562 Parallel ADC to the TMS320C54x DSP if EXTERNALCLOCK if AUTOPWDNENABLESoftware Overview endifendif if AUTOPWDNENABLESoftware Overview if POLLINGDRVendif if AUTOPWDNENABLESoftware Overview if INT0DRIVENif SAVEINTOMEMORY Software Overviewendif endifConstants definition - see 8.6.1.1 Constants.asm 8.6.6 Mono Continuous ModeMainprogram MONOCON1.asm Interrupt Routine handler - see 8.6.1.2 Interrupt VectorsSoftware Overview Interfacing the TLV1562 Parallel ADC to the TMS320C54x DSPendif Software Overviewif SENDOUTSERIAL if R8BITRESOLUTendif if DIFFINPUTMODE Software Overviewendif if EXTERNALCLOCK endifendif if SAVEINTOMEMORY Software Overviewif SENDOUTPARALLEL endif if SENDOUTSERIALendif Software Overviewendif if SAVEINTOMEMORY Interfacing the TLV1562 Parallel ADC to the TMS320C54x DSPConstants definition - see 8.6.1.1 Constants.asm 8.6.7 Dual Continuous ModeMainprogram DUALCON1.asm Interrupt Routine handler - see 8.6.1.2 Interrupt VectorsSoftware Overview Interfacing the TLV1562 Parallel ADC to the TMS320C54x DSPendif Software Overviewif SENDOUTSERIAL if R8BITRESOLUTendif if DIFFINPUTMODE Software Overviewendif if EXTERNALCLOCK endifendif if SAVEINTOMEMORY Software Overviewif SENDOUTPARALLEL endif if SENDOUTSERIALSoftware Overview Interfacing the TLV1562 Parallel ADC to the TMS320C54x DSPConstants definition - see 8.6.1.1 Constants.asm 8.6.8 C-CallableMainprogram C1562.c Interrupt Routine handler - see 8.6.1.2 Interrupt VectorsSoftware Overview Interfacing the TLV1562 Parallel ADC to the TMS320C54x DSPSoftware Overview 88 SLAA040AR7+ = data@ADSAMPLE Software Overview= bit*AR5,15-0 Interfacing the TLV1562 Parallel ADC to the TMS320C54x DSPVectors.asm Software Overview90 SLAA040 int2 returnenable 48 external interrupt int2 nop Software OverviewInterfacing the TLV1562 Parallel ADC to the TMS320C54x DSP File Linker.lnk COMMAND FILE Auto.batLinker.cmd title ”COMMAND FILE FOR TLV1562.ASM”9 Summary 10 References