Item value


Value indicates the value that was last obtained from the OPC server for the item defined by the ItemID property. The data type of the value is given by the DataType property.

The value returned from the server may be different from the value of the device to which the ItemID refers, if the DeadbandPercent for the daitem object's parent group is not zero. The value is also updated only periodically, based on the parent group's Active and UpdateRate properties.

You determine the validity of Value by checking the Quality property for the item.

Value is updated when you perform an asynchronous or synchronous read operation or when a subscription callback occurs.




Applies to


Data type

Any MATLAB® data type


The default value is an empty matrix ([]).

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