Texas Instruments TMS320 DSP manual Inter-Algorithm Synchronization

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Inter-Algorithm Synchronization

It is important to notice that preemptive systems might have groups of algorithms that execute with the same priority. A well-designed DMA manager would assign the same physical channels to algorithms at the same priority level to avoid the scenarios described in Section 6.15.4 and Section 6.15.5. This, of course, requires at least one physical channel for each priority level, which might not always be the case.

In summary, sharing a DMA device among algorithms at different priorities can be accomplished in several different ways. In the end, it is the system integrator'schoice based on its available resources.

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Use of the DMA Resource

SPRU352G –June 2005 –Revised February 2007

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Contents Users Guide Rules and GuidelinesSubmit Documentation Feedback Contents Use of the DMA Resource Urls List of Figures Document Overview Read This FirstIntended Audience Rule n Related DocumentationText Conventions Guideline nOverview Scope of the Standard Rules for TMS320C5x Rules for TMS320C6xRules and Guidelines Requirements of the StandardGoals of the Standard Intentional OmissionsSystem Architecture FrameworksAlgorithms Core Run-Time SupportGeneral Programming Guidelines Threads Use of C LanguageThreads and Reentrancy RulePreemptive vs. Non-Preemptive Multitasking ReentrancyExample Data Memory Data MemoryMemory Spaces Scratch versus PersistentScratch vs Persistent Memory Allocation Algorithm versus Application GuidelineSection Name Purpose Program MemoryROM-ability Use of Peripherals Use of PeripheralsAlgorithm Component Model Interfaces and Modules Algorithms PackagingInterfaces and Modules Implementation Fir.hExternal Identifiers Module Instance Objects Naming ConventionsModule Initialization and Finalization Design-Time Object Creation Run-Time Object Creation and DeletionModule Configuration Example ModuleMultiple Interface Support Element Interface InheritanceSummary Description RequiredAlgorithms AlgorithmsPackaging Object CodeHeader Files Debug Verses ReleaseModuleversvendorvariant.1arch Algorithm Performance Characterization Data Memory Program Memory Interrupt Latency Execution TimeSize Heap MemoryExternal Stack Memory Static Local and Global Data MemoryData Bss Object files Size Mips Is Not Enough Interrupt LatencyExecution Time OperationExecution Time Model Execution Timeline for Two Periodic Tasks59000 198000 Process198000 Submit Documentation Feedback DSP-Specific Guidelines CPU Register Types Register TypesEndian Byte Ordering Use of Floating PointTMS320C6xxx Rules and Guidelines Data ModelsRegister Use Type Register ConventionsStatus Register CSR Field Use TypeProgram Models Interrupt LatencyTMS320C54xx Rules and Guidelines TMS320C54xx Rules and Guidelines ST1 Field Name Use Type Status RegistersST0 Field Name Use Type Pmst Field Name Use Type TMS320C55x Rules and GuidelinesStack Architecture Relocatability ExampleSSP ST3 Field Name Use Type Status BitsST2 Field Name Use Type Homy TMS320C24xx Guidelines GeneralTMS320C28x Rules and Guidelines TMS320C28x Rules and GuidelinesXAR0 M0M1MAP Use of the DMA Resource Submitting DMA Transfer RequestsOverview Algorithm and FrameworkRequirements for the Use of the DMA Resource Logical ChannelData Transfer Properties Data Transfer SynchronizationDMA Rule Abstract InterfaceDMA Guideline Average Maximum Resource CharacterizationData Transfers bytes Frequency Runtime APIs Strong Ordering of DMA Transfer RequestsSubmitting DMA Transfer Requests Device Independent DMA Optimization GuidelineCache Coherency Issues for Algorithm Producers 13 C6xxx Specific DMA Rules and GuidelinesSupporting Packed/Burst Mode DMA Transfers 14 C55x Specific DMA Rules and GuidelinesInter-Algorithm Synchronization Minimizing Logical Channel Reconfiguration OverheadAddressing Automatic Endianism Conversion Issues Non-Preemptive SystemPreemptive System Algorithm B Algorithm a Inter-Algorithm Synchronization Appendix a General Rules Performance Characterization Rules DMA RulesGeneral Guidelines DMA Guidelines Submit Documentation Feedback DSP/BIOS Run-time Support Library Core Run-Time APIsDSP/BIOS Run-time Support Library TI C-Language Run-Time Support LibraryBibliography BooksSubmit Documentation Feedback Glossary Glossary of TermsGlossary of Terms Glossary of Terms Important Notice