Technical Reference > CtAPI Functions > I/O Point Count

I/O Point Count

Physical I/O Device tags read, or written to, using the CTAPI are counted as dynamic CitectSCADA points. If the point limit is exceeded by making calls to this interface, then that call will not succeed, and CitectSCADA will not be allocated any more dynamic points.

Note:CitectSCADA's licensing works on the basis of how many points you use. Every tag in your system has the potential to add to your point count. It is important to remember this, and plan your system properly, otherwise you may exceed your point limit.

The point limit is the maximum number of I/O Device addresses (variable tags) that can be read, and is specified by your CitectSCADA license. CitectSCADA counts I/O Device addresses dynamically at runtime. This includes tags used by alarms, trends, reports, events, pages, in Super Genies, use of the TagRead() and TagWrite() Cicode functions, or read or write using DDE, ODBC, or the CTAPI.

It does not count any points statically at compile time.

When your system is running, any new use of tags through Super Genies, DDE, ODBC, or CTAPI can potentially add to your dynamic point count.

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