PI-OASyS interface

Note: For information on overriding default configuration settings, refer to Modify configuration settings.

PI-OASyS (piuniint.exe) is the name of the interface process that manages communication between the PI System and AVEVA Enterprise SCADA.

Data communication is bi-directional. The data object in PI is a point, which has a name attribute called PI Tag. The PI-OASyS interface inputs to PI from AVEVA Enterprise SCADA based on the point values residing in the RealTime database (RTDB) tables of AVEVA Enterprise SCADA. The PI-OASyS interface outputs to AVEVA Enterprise SCADA from PI based upon exceptions on point values residing in PI. The PI-OASyS interface must run on the computer that runs the RTDB service. It connects to the remote PI Server computer through TCP/IP.

The PI-OASyS interface launches as a critical process of the RTDB service. PI.run_processes.csc script calls the PI-OASyS interface and supplies it with a list of parameters. These parameters are read from the PIOASyS.json file and passed directly to piuniint.exe. The PI-OASyS interface connects to the PI Server computer, collects all configuration information for the tags that belong to the PI-OASyS interface, and sets up mapping to the RTDB records and fields based upon the tag configuration. This summarizes the interface initialization and is identical for interfaces running in both Hot and Standby computers. Thereafter, the standby interface only updates its point list when the PI Tag database is changed while the Hot interface updates its point list and actively transfers data to the PI Server. The Standby interface queries its status, and upon discovering that it has become Hot, will commence data transfers.

Note: The PI-OASyS Interface appears under the name PIUniint.exe in the system process list.