Refresh(Source)

Forces a server to resend values from all OPC Group Tags with their readings enabled, whether they changed their values or not. The Source parameter determines the argument of OPC Driver's data source. If the informed value is 1 (RefreshFromCache), sent values are server's cache values. Otherwise, if the informed value is 2 (RefreshFromDevice), values are updated in server's cache before sending. For this method to work, the OPC Group's Enable property, as well as reading at least one Tag of the OPC Group, must be enabled. For more information about this mechanism of enabling readings (the Advise mode), please check Tag's AllowRead and AdviseType properties.