To run ptq_onchange, enter the command:
ptq_onchange
The PTQ> prompt appears. You can display point values or point attribute information.
To display a point value, enter
the Point ID for the point you want to display then press
Enter.
To display attribute information
for a point, enter the Point ID for the point followed by a period
(.) and the attribute name you want to display, then press
Enter. You can use any of
the attributes documented in Point Attribute Descriptions.
Always enter the Point ID in upper-case characters since the point database is case sensitive. You will not be able to view Point IDs that contain embedded spaces.
After you press Enter, the current value for the point in the point management database is displayed. Remember that this is the current value in the database. The frequency with which the point is collected by the system is determined by the point's configured scan rate. If the configured rate is 5 seconds, there may be as much as a five second delay between changes at the controller and in the point management data base.
The point value is displayed with engineering units conversion if so configured. After the value is shown, the program waits for a new value to be received from point management. Whenever the value in the point management data base changes, that value is sent to the program, and the value is displayed on the terminal. Press Ctrl+C to terminate the program.
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Sample programs. |
