Download Data Acquisition Toolbox Adaptor Kit User's Guide

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Engine Interface Reference
modified, while a value of true indicates that the property cannot be modified
and is read only.
For example, the following code fragment creates a property called
ReadOnlyProperty that cannot be modified.
prop->put_IsReadonly(true);
If you try to set the property, you receive the following error:
set(ai, 'ReadOnlyProperty', 4)
??? Error using ==> daqdevice/set
The property: 'ReadOnlyProperty' is read-only.
This attribute should not be set to true for standard engine properties.
See Also
IDaqEngine interface: IpropContainer->CreateProperty
get_User
Syntax
HRESULT get_User(long *User)
Output Parameters
User
long*
Description
The get_User method gets the User for a property. When certain properties are
modified by you, the adaptor needs to configure the hardware appropriately.
The adaptor is notified of property value changes for any property that the
adaptor has registered with the data acquisition engine. The adaptor registers
a property by passing to the engine the address of a local data member for the
property. The address of a local data member can be stored in the User value.
When a property that has been registered by the adaptor is set by you, the data
acquisition engine calls the adaptor’s SetProperty or SetChannelProperty
method. The User value of the property is then passed to the method.
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