Varec 8315 Series manual Gwblk method

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8300	8315 L&J Tankway Software Description

Address	Type	Number	Parameter	Data Type

5018	WV1900	1	Status	HEX

5019	WV1900	1	PntStatus	IHEX

5020	WV1900	1	Elapse	TIME

4.5.3GWBLK method

The GWBLK is the preferred means to address data in the TankGate. The GWBLK has a great deal of flexibility. Data can be scaled, or grouped using the GWBLK. The Gateway Block (GWBLK) allows the user to specify data address and point reference combinations. This allows the TankGate to be used with an existing system that is already configured. The TankGate can be tailored to meet the needs of the Host. In some cases, the Host system may have some constraints in the use of its Modbus scanner that make it necessary to use a GWBLK. In this mode, the user defines a GWBLK point and specifies which database parameter will correspond to a particular data address. When a request from a master is received, the Modbus Slave protocol handler will first search for any GWBLK points and determine if the data address of the request is specified in one of the GWBLK points. If the data address is contained in a GWBLK point, then the corresponding point reference is used to provide the data for the reply to the master. If the data address is not in any GWBLK point, then data will be read using the prevailing Address Mode.

The Gateway Block (GWBLK) allows the user to specify data address and point reference combinations. The GWBLK acts as a lookup table for data items in the TankGate. The user defines a GWBLK point and specifies which database parameter will correspond to a particular data address. When a request from a master is received, the Modbus Slave protocol handler will search for any GWBLK points and determine if the data address of the request is specified in one of the GWBLK points. If the data address is contained in a GWBLK point, then the corresponding point reference is used to provide the data for the reply to the master.

The procedure for using the GWBLK is given below:

•Add a GWBLK point. Depending upon the addressing requirements of the host system, it may be necessary to add additional GWBLKs.

•Configure the GWBLK by setting the Address, PntRef and Size parameters to the parameters of interest in the TankGate. Refer to the following example:

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Contents Installation Operations Manual Page Copyright Disclaimer of Warranties Safety Precaution Definitions Safety Precautions Using ViewRTU InstallationTroubleshooting and maintenance OverviewContents System Information SYS Using ViewRTU Troubleshooting Applications FeaturesVersions Power Supply Specifications System DesignPower consumption Operating temperatureMechanical Construction Storage temperatureHumidity Overview TankGate Interface Hardware Motherboard Description Hardware Block DiagramTankGate motherboard Field Power Vfield terminal block J3 Unit AC Input Power terminal block J2Auxiliary DC Output Power terminal block J8 Surge Protection Surge Gnd terminal block J4Field Voltage Selection Jumper W3 AC Power Fuses F1,F2Hard Reset Switches and IndicatorsReset push-button SW3 3.1 COM0 J7 Communications3.2 COM1 RS-232/RS-485 J5 3.3 COM1 RS232/RS-485 Selection Switch SW23.4 COM1 Hardware Handshaking Switch SW1 SW2 Set Tion Physical Handshak Ting Layer Ing Communica HardwareWith RTS / CTS RS-232J6 TankGate Communications Cable8315 L&J Tankway Interface Module Model 8315 TankGate DescriptionLED Indicators D1-D6 ID DIP Switch SW1Surge/Shield Ground Connector J4 External Power Connector +48V J2Connect the field wiring Field Wiring terminal block J38315 L&J Tankway Interface Module TankGate Interface Real-Time Clock Software Features Real-Time / Multitasking ExecutiveAutomatic Fault Recovery Data Scanning Task ProtocolsDatabase Manager System TasksTankGate 8315 Software Blocks TankGate Software BlocksPoint Format Database OrganizationParameter Description Parameter ClassesData Format Description Parameter Data FormatsCommon Parameters PntStatus Parameter PntCheckSum ParameterElapse Parameter Value ParameterStandard Request-Response Format Gathering Point DataChange of State Format Change of State-Related ParametersDeadband Modbus Slave Modbus CommunicationsAddress Type Number Parameter Data Type Fixed Modbus MapFunction Code Description Comments Gwblk method 8315 L&J Tankway Software Description TankGate Interface Data Address Parameter Comments Clock CLK Configuration Parameters FunctionParameters Dynamic Parameters FunctionCommunications COM Configuration Function ParametersApplication Real 4 bytes value Floating Point Register FpregDynamic Function Parameters API Emulator EMUByte value indicating status of point Values are Current Command Configuration Parame Function TersEMU Gateway Emugw Hex representation of the request sent by the hostDisplays the tank number of the currently selected tank Gauging Systems Inc. Model 2000 Interface GS2000 Last message. The maximum is 255 seconds. The default is Raw2 Gateway Block Gwblk CRC-16 Checksum of points static Configuration Parameters Byte value indicating status of point Values are No errorSize Parameter Addr1 is the Data Address and PntRef1 is the correspondingInteger 2 bytes value Integer Register IregCurrent request message, displayed in hex format Modbus Gateway ModgwCurrent command. Values include Dynamic Parame Function Ters Scaler Point ScalerOutput value for the Scaler point Value = Ax + By + Cz + KValue parameter converted to Integer format System Information SYS 17 L&J MCG1000 Tank Gauge LJ1000 PntStatus will be set to indicate the failure Application 18 L&J MCG1500 Tank Gauge LJ1500 Task on the Motherboard determines that the Model 8315 has 8315 L&J Tankway Software Description TankGate Interface 19 L&J MCG2000 Tank Gauge LJ2000 Enables the watchdog task on the Motherboard. The watchdog 8300 Number of gauge polls since last reset Command currently being sent to the gaugeNumber of gauge polls which resulted in an error 20 L&J Scanner LjscanOut 8315 L&J Tankway Software Description TankGate Interface Installation Safety Guidelines General Safety GuidelinesInstallation Mounting the TankGate inside the enclosure Mounting the TankGateInstalling Communications Wiring Up PowerMounting the Enclosure Select the Unit addressRS-485 Communications Power-UpInitial system verification Establishing Host CommunicationsInstallation TankGate Interface Overview Installing ViewRTUSystem Requirements Executing ViewRTUViewRTU Version Selection dialog File Menu ViewRTU windowViewRTU Menu Bar Point Menu Edit Point selection dialog Select Point to Add dialog boxEdit Point deletion dialog Edit Point dialogDelete Upload Database from TankGate Config MenuDownload Database to RTU Creating a Password To enter the passwordChanging the Password Changing the PasswordPC Setup Communications MenuStatus Port Communications Setup dialogTankGate search dialog Options MenuConnect Convert ViewRTU versions dialog Convert Configuration FilesExport All Import AllHelp Menu Using ViewRTUConfiguring Single Points Minimize Edit Digital Point dialogEdit Point Window Push-buttons Connections Minimizing the Edit Point WindowNext PreviousUpload To modify a ValueTo modify a value Edit point parameter value dialogTo modify a Reference Configuring Multiple PointsEdit point parameter reference dialog Adding Multiple PointsAdding Multiple Points Spreadsheet ModeEdit Menu Point MenuCopy PasteSet Value with Auto Increment Paste & DnldSet Value Export Options MenuImport Parameter Type Description ViewHide Row/Col Unhide All Creating and Editing ConnectionsTo create a Connection Displaying the Point Connections windowPoint Connections Window Using ViewRTU TankGate Interface Indicator Condition Run indicatorCommunications indicator Using the TankGate Push-buttonsLED Displays under Abnormal Conditions 1.3 TXD/RXD LEDsPress the Reset button Performing a Hard ResetSet the ID DIP switch to the desired addresses Replacing a defective component or module MaintenanceTroubleshooting TankGate Interface 102 Ordering Structure Nema 4 Enclosure Ordering Structure Remote Terminal Unit TankGateModbus Map Value12 Fpreg 3034 3094 8300 Your official representative Your offical representative