Xilinx UG154 manual Timing Simulation Warning and Error Messages

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Appendix D

Timing Simulation Warning and Error Messages

There are several common simulation warnings and error messages when timing simulation is run on the example design. These warnings and messages are described in this appendix.

"# TDat Error: Data Mismatch # 4. Expected 000f, Received 000x. 339280 ps"

The data mismatch results from the data going to unknown "x" state. To prevent "x" from propagating in your simulation, use the "+no_notifier" option to vsim command when using ModelSim Simulator (MTI). If you are using other simulators, consult the manufacturer documentation for possible ways to turn off "x" propagation.

SETUP, HOLD, RECOVERY violation on /X_FF

These violations might come from either the Sink core or Source Core, and they originated from register elements that are transiting between two clock domains. These timing violations can be safely ignored.

When running simulation on a SPI-4.2 Sink Core with Global Clocking and DPA Clock Adjustment option, the signal Locked_RDClk (from RDClk DCM) might get deasserted after PhaseAlignRequest is asserted. When the PhaseAlignRequest has been asserted, the IDELAY goes through the reset process and the clock stops toggling momentarily. This might cause the lock signal from the DCM to get deasserted in simulation (this does not occur in hardware testing). Locked_RDClk should be ignored after the PhaseAlignRequest has been asserted in simulation.

"Memory Collision Error on X_RAMB16"

The "Memory Collision" error occurs occasionally because the calendar block is trying to read out values at the same time that you are writing them in; however, this is not a problem because you are only supposed to write the calendar when the core is disabled.

SPI-4.2 v8.5 Getting Started Guide

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UG154 March 24, 2008

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Contents UG154 March 24 LogiCORE IP SPI-4.2 CoreSPI-4.2 v8.5 Getting Started Guide Date Version Revision Revision HistorySPI-4.2 v8.5 Getting Started Guide Table of Contents Appendix a Vhdl Details 1Core Customization GUI Main Window Schedule of FiguresSPI-4.2 v8.5 Getting Started Guide Table B-5sopspacing Bytes1, Err1, Addr1, EOP2, Err2, Addr2 Schedule of TablesSPI-4.2 v8.5 Getting Started Guide Contents About This GuideConventions Online Document TypographicalPreface About This Guide Convention Meaning or Use ExampleSystem Requirements IntroductionAbout the Core Recommended Design ExperienceTechnical Support Additional Core ResourcesFeedback CoreBefore you Begin Licensing the CoreLicense Options Simulation-Only EvaluationObtaining Your License FullLicensing the Core Installing Your License File Installing Your License FileLicensing the Core Quick Start Example Design OverviewGenerating the Core 1Core Customization GUI Main Window Quick Start Example DesignImplementing the Example Design Setting up for SimulationRunning the Simulation Functional SimulationTiming Simulation Running the Simulation Quick Start Example Design Project directory Detailed Example DesignDirectory and File Contents Directory and File Contents 3Doc Directory Component name/example design4Example Design Directory Name Description 5Implement Directory Name Description Component name/implementImplement/results Directory and File ContentsComponent name/simulation 6Results Directory Name Description8Functional Directory Name Description Simulation/functionalSimulation/timing Implementation and Simulation ScriptsImplementation and Simulation Scripts 9Timing Directory Name DescriptionSimulation Script Details Example Design ConfigurationExample Design Configuration Loopback ModuleBasic Loopback Operation Demonstration Test Bench Connections Demonstration Test BenchDemonstration Test Bench Clock GeneratorStartup Module 4Startup State DiagramCalendar Loader Stimulus ModuleProcedures Module Data MonitorStatus Monitor Customizing the Demonstration Test Bench Constant Default Value DescriptionTest Case Package 10Testcase Package User-Defined ConstantsTestdatafile Testcase Module Constant Default Value Description Type Range12Testcase Module Request Signals Name Function 11Useful Testcase Signals Name DescriptionCalendar Sequence Files Sink and Source Detailed Example Design Vhdl Details Procedures ModuleTable A-3sendidles PBr, cycles Inputs Name Range Description ADDR2 Appendix a Vhdl Details Verilog Details Table B-3sendidles cycles Inputs Name Range Description Appendix B Verilog DetailsTable B-7getstatus channel Inputs Range Description Random Testcase Sample CodeAppendix B Verilog Details Random Testcase Sample Code Appendix B Verilog Details Data and Status Monitor Warnings Appendix C Data and Status Monitor Warnings SETUP, HOLD, Recovery violation on /XFF Timing Simulation Warning and Error MessagesAppendix D Timing Simulation Warning and Error Messages

UG154 specifications

Xilinx UG154 is a comprehensive user guide that provides in-depth information about the architecture, features, and technologies of Xilinx's FPGA (Field Programmable Gate Array) devices. This guide is particularly vital for developers, engineers, and designers who work with Xilinx products, as it serves as a key resource throughout the development lifecycle.

One of the main features of Xilinx UG154 is its coverage of the device architecture, which details the programmable logic cells, configurable interconnects, and I/O capabilities. Xilinx FPGAs are known for their flexibility and scalability, allowing designers to implement complex digital circuits and systems that can be modified post-manufacturing, enabling rapid prototyping and iterative design processes.

Another key aspect highlighted in UG154 is the technological advancements in the latest Xilinx architectures, such as UltraScale and UltraScale+. These architectures incorporate advanced process technologies, providing improved performance and power efficiency. High-speed serial transceivers, embedded processing capabilities, and extensive memory options are also discussed, showcasing how these features enhance system integration and reduce design time.

The guide also delves into Xilinx's software ecosystem, featuring the Vivado Design Suite, which streamlines the design process through integrated design tools and a unified development environment. The Vivado suite supports various high-level synthesis, simulation, and analysis tools, facilitating a smoother transition from concept to implementation.

In addition to hardware and software integration, UG154 covers the importance of IP cores, which are pre-designed functional blocks that can be easily integrated into FPGA designs. Xilinx provides a vast library of IP cores, ranging from basic logic functions to sophisticated signal processing algorithms, enabling engineers to accelerate development without sacrificing performance.

Another focus of UG154 is the emphasis on design best practices and optimization techniques that can be employed to maximize the capabilities of Xilinx devices. Topics such as timing closure, resource optimization, and power management are among the critical areas addressed, which help designers achieve the desired performance within the constraints of their applications.

Overall, Xilinx UG154 serves as a vital resource that equips engineers with the knowledge and tools necessary to leverage the full potential of Xilinx FPGAs. By understanding the features, technologies, and architectural characteristics detailed within this guide, designers can create innovative solutions across a range of applications, including telecommunications, automotive, aerospace, and industrial automation.
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