| Active after start | If checked, then the group becomes active immediately after the application is launched.
This configurator sets the initial value of the ActiveGroup property. |
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| Refresh from server at server change | If checked, then automatic data refresh from server right after the application is launched is enabled (the data to be refreshed are defined on the "Data" tab and the data in the PmaData object containing ExtOpcDa).
This configurator sets the initial value of the Update property. If this configurator is not set, then the data can be received by method Refresh or Read. |
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| Minimum update rate [ms] | Rate in milliseconds. At the automatic update the OPC server will not send data faster than it is set here.
This configurator sets the initial value of the UpdateRate property. |
| Deadband [%] | At the automatic update the OPC server will not send data that changed less than entered here.
This configurator sets the initial value of the Deadband property. |
| "onDataReceive" event | The onDataReceive event triggering type. The OPC server usually sends multiple data items simultaneously and here it is defined for which received variables the event is triggered and what will be saved in the pEvent.Items parameter of this event.
A = call the event for all registered variables (in this object and also in other PmaData objects) - The event is triggered for all variables that have received values. These are:
- variables defined in this PmaOpcDaClientGroup object on the "Data" tab.
- variables defined in the PmaData object that have ExtOpcDa data extension registered into this PmaOpcDaClientGroup object.
In the onDataReceive event, in the pEvent.Items parameter there will be a list of data extensions of these variables (of ExtOpcDa objects). B = calling for the whole group of received variables - only for variables defined in this object (obsolete) - The event is triggered only for variables that have received values that were defined in this object on the "Data" tab. The event is triggered only once for each received group of variables.
In the onDataReceive event, in the pEvent.Items parameter, there will be a list of variables (of PmVar objects). C = calling for each variable separately - only for variables defined in this object (obsolete) - The event is triggered only for variables defined in this object on the "Data" tab, that have received values. The event is triggered for each variable individually. For example if there is agroup of 100 variables received, then the event is triggered 100 times. That is the main reason why this approach is not recommended for large volumes of data items.
In the onDataReceive event it is possible to check the received variables in the pEvent.VarName parameter. |
| Auto send to server when writing to item | If checked, then at any writing into the variable the value of this variable is immediately written to the OPC server (at writing into data defined on the "Data" tab and at writing into the PmaData object data containing ExtOpcDa).
If you write into more items of this object at a time, then the transmission is invoked for each item separatelly! Then it is better to disable this configurator and to send the data by the Write method. Caution! Writing to the OPC is called only if the real write is performed (e.g. object.Item(0).Value=3) into the item - let's mark it A. But if the data binding (during the reading) to another item B (in another object) is defined in the item A and it is written into the item B, then the item A doesn't know about the change and nothing is sent to the OPC server (the item A does know about the change only when it is read by someone - data binding is then "performed"). |
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