Black Box GEH-6510 manual Optimizing Server Performance, Server Operational Parameters

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Optimizing Server Performance

Networks vary widely from one to another. Every network has different devices, different numbers of RS-485 ports to support, a different number of devices, and various client software requesting different amounts of data. System administrators with Modbus RTU network experience may be able to analyze their particular network’s needs and adjust some of the PMCS DDE Server’s advanced settings to improve its performance. These settings are discussed below.

Server Operational Parameters

Clicking on this button in the Configuration dialog box causes the Server

Operational Parameters dialog box to appear:

Protocol Timer Tick

The Protocol Timer Tick is the time interval (in milliseconds) at which protocol is executed; the frequency at which the Server checks for work to do. A good analogy might be that the protocol timer tick serves as a metronome or heartbeat to the Server. Every tick, the Server executes a function, whether it is to listen at a particular port or to send a message to a device. The default is 65 milliseconds. At values below this level, the Server may query devices too quickly for the devices to consistently answer correctly.

The Protocol Timer Tick is the resolution of the scan interval – increasing this value slows down the Server but may improve communication reliability. Decreasing this value reduces communication reliability but may slightly speed up data-refresh rates. If you are not sure how to adjust this value for your network, leave it set at 65 msec.

NOTE: 10 msec is the minimum value for this setting.

Valid Data Time-out

A client application sends a request for data to the PMCS DDE Server. The Valid Data Time-outis the time (in milliseconds) that elapses before a time-out error message is sent to the client that requested the data. The default number in this field is 5000 (5 seconds). If no reply is sent from the Server to the client in this length of time, a time-out error message is sent instead.

76 Chapter Six - Advanced Options

DDE Server User’s Guide

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Contents Power Leader TM DMMS425 Back to Main Menu Contents Glossary of Terms This page left blank intentionally Welcome Chapter One IntroductionAbout NetDDE About DDEServer with OPC Interfaces InstallationAbout the Pmcs DDE Server EI User’s onlyChapter One Introduction DDE Server User’s Guide Running Pmcs DDE Server as an NT Service About Pmcs Chapter Two OverviewChapter Two Overview DDE Server User’s Guide Sample register map DevicesWhat’s Next NetworksPmcs DDE Server Client ApplicationsIntroduction First-Time ConfigurationDevice Configuration Chapter Three Getting StartedWhat’s on the DDE Server Screen? Launching the ProgramMenu Conventions Menu BarConfiguring Communication ports EPM 7700 Xpress Card or Xplex 1620 Max Server Users Ethernet Users OnlyChapter Three Getting Started DDE Server User’s Guide Modbus TCP/IP Server Users Chapter Three Getting Started DDE Server User’s Guide Configuring the Devices Device Name Topic Com Port Starting the ServerDisplaying I/O Traffic DDE Server User’s Guide Chapter Three Getting Started NetDDE Setup Overview Automatic NetDDE Setup VNDDE.EXEUtility VNDDE.EXE Error Messages Tips on using VNDDE.EXEResults Additional Help Manual NetDDE SetupTrouble-Shooting VNDDE.EXE VNDDE.EXE FAQ’sChapter Three Getting Started DDE Server User’s Guide DDE Server User’s Guide Chapter Three Getting Started Chapter Three Getting Started DDE Server User’s Guide This page left blank intentionally System Menu Chapter Four Menus and ToolbarsRun Server MenuStop Exit View MenuSuspend Protocol/Resume Protocol Print I/O TrafficDisplay Traffic DisplayColor Add Device BackgroundDelete Clear DisplayRegister groups for display Port Statistics Configure MenuConfiguration Save Display To FilePorts Modbus or EI ConfigureDDE Server User’s Guide Chapter Four Menus and Toolbars Ethernet Gateway Users Ports Ethernet onlyEPM 7700 Xpress Card or Xplex 1620 Max Server Users Chapter Four Menus and Toolbars DDE Server User’s Guide Modbus TCP/IP Server Users Chapter Four Menus and Toolbars DDE Server User’s Guide Device Info AddChapter Four Menus and Toolbars DDE Server User’s Guide Device Type Information ModifyDelete Activate checkboxGeneric Comm Interface DDE Server User’s Guide Chapter Four Menus and Toolbars Active Links Reports MenuToolbar Help MenuTrouble-Shooting the Pmcs DDE Server Chapter Five TroubleshootingWWLogger Communications Client to Server Communications Server to Device NetDDE Trouble-Shooting Trouble-Shooting Flowchart Error Messages Trouble-Shooting ChartCServerAppOnDeleteDev Invalid toolkit index Device device name Active Failed to delete itemlogical device handle, Protocol Handle No Write to Individual Discrete Bits Device type device type name is not a valid type for topic This page left blank intentionally Device Type Information Adding Generic Devices Chapter Six Advanced OptionsAdd Default Type Function Codes Register Map Type Code Type of Register Supported Function Codes Use Adding a Register GroupDDE Server User’s Guide Chapter Six Advanced Options Invalid Register Blocks Modifying a Register Group Modifying an Invalid Register BlockDeleting an Invalid Register Block Deleting a Register GroupImporting or Exporting a Register Group MnemonicsImporting or Exporting Mnemonics Adding a MnemonicModifying a Mnemonic Deleting a MnemonicValid Data Time-out Protocol Timer TickOptimizing Server Performance Server Operational ParametersCommunication Time-out Pmcs DDE Server .ini FileSlow Poll Count TimeDownLoad Period Maximum Query RetriesDead Device Scan Interval SleepTime For ExceptionUIHide ExitDisableData-Addressing Conventions Appendix a Register Addressing ConventionsData Types Standard Data OrganizationExamples Special Naming ConventionsLong Words and Special Numbers XnnnnDL-B Individual Bits In RegistersRegister Array Format This page left blank intentionally Terms You Should Know Glossary of TermsGlossary of Terms DDE Server User’s Guide Index GE Industrial Systems