Contents
SLAA040
July
Application Report
TParalInteMS3rflelADConvertertotheacing20C54xDSPtheTLV1562
IMPORTANT NOTICE
Contents
8.5.5
List of Tables
List of Figures
Figures
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1 Introduction
Interfacing the TLV1562 Parallel ADC to the TMS320C54x DSP
2 The Board
2.1 TMS320C54x Starter Kit
2.3 ADC TLV1562 Overview
2.2 TLV1562EVM
2.3.1 Suggestions for the ’C54x to TLV1562 Interface
2.3.1.1 The Universal Interface
2.3.2 Recyclic Architecture
Using RD or the CSTART Signal to Start Conversion
Figure 2. TLV1562 to ’C54x DSP Interface of the EVM
2.4 Onboard Components
2.3.3 Note on the Interface, Using an External ADC Clock Drive
2.4.1 TLC5618A - Serial DAC
Figure 3. TLC5618A to ’C542 DSP Interface
2.4.2 THS5651 - Parallel Output CommsDAC
Figure 4. THS5651 to C542 DSP Interface
3.1 Reference Voltage Inputs
3 Operational Overview
3.2 Input Data Bits
3.3 Connections Between the DSP and the EVM
Table 1. Signal Connections
Table 2. 3-Position Jumpers
3.3.1 Jumpers Used on the TLV1562EVM
Table 3. 2-Position Jumpers
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Table 4. DSP/DAC Interconnection
4 The Serial DAC/DSP System
5 The DSP Serial Port
Table 5. DSP Serial Port Signals and Registers
6.1 DSP Internal Serial Port Operation
6 Other DSP/TLV1562 Signals
7 Conversation Between the TLV1562 and the DSP
7.2 Mono Interrupt Driven Mode Using RD
7.1 Writing to the ADC
Table 6. DSP Algorithm for Writing to the ADC
tDCSL-sample+1ADCSYSCLK
Table 7. DSP Algorithm for Mono Interrupt Driven Mode Using RD
tENDATAOUT = 41 ns
Table 8. DSP Algorithm for Mono Interrupt Driven Mode Using CSTART
7.3 Mono Interrupt Driven Mode Using CSTART
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Table 9. DSP Algorithm for Dual Interrupt Driven Mode
7.4 Dual Interrupt Driven Mode
Table 10. DSP Algorithm for Mono Continuous Mode
7.5 Mono Continuous Mode
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Table 11. DSP Algorithm for Dual Continuous Mode
7.6 Dual Continuous Mode
8.1 Software Development tools
8 Software Overview
8.2 DSP Memory Map
Figure 5. Memory Map
8.3 Programming Strategies for the ’C54x, Explanations
8.3.3 Timer Output
8.3.1 Optimizing CPU Resources for Maximum Data Rates
8.3.2 Address and Data Bus for I/O Tasks
8.3.4 Data Page Pointer
8.3.5 Generating the Chip Select Signal and the CSTART Signal
8.3.6 Interfacing the Serial DAC 5618A to the DSP
8.3.8 Branch Optimization goto/dgoto, call/dcall
8.3.7 Interrupt Latency
GOTO MARK
MARK DP = #1 ARP = #5
8.4 Software Code Explanation
8.3.9 Enabling Software Modules .if/.elseif/.endif
8.4.1 Software Principals of the Interface
8.4.1.1 Software Polling
8.4.1.2 Timed Solution
Advantage
Disadvantage
8.4.1.5 Setting the Right Switches
8.4.1.3 Interrupt Driven Solution
Advantages
Disadvantages
Task
Table 12. Switch Settings
Table 13. Instruction in the Program Header Step
8.5.1 The Mono Interrupt Driven Mode Using RD to Start Conversion
8.5 Flow Charts and Comments for All Software Modes
Table 14. Instruction in the Program Header Step
8.4.1.6 Common Software for all Modes
Other Files
Program Files
Code verification
common file of all modes constants definition
Figure 6. Software Flow of the Mono Interrupt Driven Solution
Calibration procedure of the DAC
8.5.2 Mono Interrupt Driven Mode Using CSTART to Start Conversion
Includes the complete software algorithm to control the monomode
Common file of all modes constants definition
SAVE
Initialize SPI
Poll INTO Pin Until h/0 Transition Occurs
Pull Down CSTART
This only works for one TLV1562 not multiple because CS is not used
8.5.2.1 Throughput Optimization†
Figure 8. Time Optimization monocst1
8.5.3 Dual Interrupt Driven Mode
Maximum Performance at 1.2 MSPS with Internal Clock
IMPORTANT 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
Interfacing the TLV1562 Parallel ADC to the TMS320C54x DSP
8.5.4 Mono Continuous Mode
Figure 10. Flow Chart Mono Continuous Mode
8.5.5 Dual Continuous Mode
Figure 11. Flow Chart Dual Continuous Mode
Other Files
8.6.1 Common Software for all Modes except C-Callable
8.6 Source Code
8.6.1.1 Constants.asm
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set 000C0h Operate without calibrated inputs no offset
8.6.1.2 Interrupt Vectors
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4C internal timer interrupt
8.6.1.4 Auto.bat
8.6.1.3 linker,cmd
File Linker.lnk COMMAND FILE
title ”COMMAND FILE FOR TLV1562.ASM”
pointer address when using any of the following variables
Mainprogram Monomode.asm
jump address to init. new channel
counter for one channel
sent value to register CR0 of the ADC
endif if INT0DRIVENPOLLINGDRV
if SENDOUTSERIAL
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endif
endif if DIFFINPUTMODE
if AUTOPWDNENABLE
= bit*AR5,15-0
elseif INT0DRIVEN
elseif NOINT0SIG
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CALIBRAT.ASM
8.6.3 Calibration of the ADC
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if SMECALIBRATION
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endif
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Interfacing the TLV1562 Parallel ADC to the TMS320C54x DSP
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if INT0DRIVENPOLLINGDRV
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= bit*AR5,15-0
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endif if SAVEINTOMEMORY
endif
Constants definition - see 8.6.1.1 Constants.asm
8.6.5 Dual Interrupt Driven Mode
Interrupt Routine handler - see 8.6.1.2 Interrupt Vectors
Mainprogram DUALIRQ1.asm
Interfacing the TLV1562 Parallel ADC to the TMS320C54x DSP
Software Overview
if SENDOUTSERIAL
Software Overview
endif
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Software Overview
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endif
Mainprogram MONOCON1.asm
8.6.6 Mono Continuous Mode
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Interfacing the TLV1562 Parallel ADC to the TMS320C54x DSP
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endif if EXTERNALCLOCK
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endif if SAVEINTOMEMORY
Mainprogram DUALCON1.asm
8.6.7 Dual Continuous Mode
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Interfacing the TLV1562 Parallel ADC to the TMS320C54x DSP
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endif if EXTERNALCLOCK
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Interfacing the TLV1562 Parallel ADC to the TMS320C54x DSP
Mainprogram C1562.c
8.6.8 C-Callable
TLV1562Channel, Save Memory Start address, NUMBEROFSAMPLES
80h samples of channel 1 will be stored beginning on 2000h
Interfacing the TLV1562 Parallel ADC to the TMS320C54x DSP
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AR7+ = data@ADSAMPLE
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Vectors.asm
int2 returnenable 48 external interrupt int2 nop
Linker.cmd
Auto.bat
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10 References
9 Summary
