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opchelp

(To be removed) Help for OPC data access function or property

Support for the OPC Data Access (DA) standard will be removed in a future release. Instead use OPC Unified Architecture (UA). See Version History.

Syntax

opchelp
opchelp('Name')
Out = opchelp('Name')
opchelp(Obj)
opchelp(Obj,'Name')
Out = opchelp(Obj,'Name')

Description

opchelp displays a listing of OPC data access functions with a brief description of each function.

opchelp('Name') displays online help for the function or property, Name. If Name is a class, a complete listing of the functions and properties for that class is displayed with a brief description of each. The online help for the object constructor for that class is also displayed. If Name is a class with the .m extension, then only the online help for the object constructor is displayed.

You can display object-specific function information by specifying Name to be object/function. For example, to display the online help for the data access object's connect function, Name would be 'opcda/connect'.

You can display object-specific property information by specifying Name to be object.property. For example, to display the online help for the data access object's Status property, Name would be 'opcda.Status'.

Out = opchelp('Name') returns the help text to the variable Out.

opchelp(Obj) displays a complete listing of functions and properties for the OPC object Obj, along with the online help for the object constructor.

opchelp(Obj,'Name') displays the help for function or property, Name, for the toolbox object Obj.

Out = opchelp(Obj,'Name') returns the help text to the variable Out.

When displaying property help in the command window, the names in the “See also” section that contain all uppercase letters are function names. The names that contain a mixture of uppercase and lowercase letters are property names.

When displaying function help, the “See also” section contains only function names.

Examples

Display all OPC data access functions and a brief description of each function.

opchelp

Display help on the opcda constructor.

daHelp = opchelp('opcda')

Display help on the OPC set function.

opchelp set

Display help on the opcda object disconnect function.

opchelp opcda/disconnect

Create an opcda object and query help information on that object. Get the help for the Timeout and Status properties.

da = opcda('localhost','Matrikon.OPC.Simulation'); 
opchelp(da)
timeoutHelp = opchelp(da,'Timeout');
opchelp(da,'Status');

Version History

Introduced before R2006a

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See Also

Functions