Data Acquisition Toolbox

Configuring and Returning Properties

You define and evaluate the behavior of your data acquisition application with device object properties. You define your application behavior by assigning values to properties with the set function or the dot notation. You evaluate your application configuration and status by displaying property values with the get function or the dot notation.

Property Types

Data Acquisition Toolbox properties are divided into two main types:

• Common properties -- Common properties apply to every channel or line contained by a device object.
• Channel/Line properties -- Channel/line properties are configured for individual channels or lines.

The relationship between an analog input object, the channels it contains, and their properties is shown below.

For digital I/O objects, the diagram would look the same except that lines would be substituted for channels.

Common properties and channel/line properties are subdivided into these two categories:

• Base properties -- Base properties apply to all supported hardware subsystems of a given type, such as analog input. For example, the SampleRate property is supported for all analog input subsystems regardless of the vendor.
• Device-specific properties -- Device-specific properties apply only to specific hardware devices. For example, the BitsPerSample property is supported only for sound cards. Note that base properties can have device-specific values. For example, the InputType property has a different set of values for each supported hardware vendor.

The relationship between common properties, channel/line properties, base properties, and device-specific properties is shown below.

For a complete description of all properties, refer to Base Property Reference, or Device-Specific Property Reference.

Mapping Hardware Channel IDs to MATLAB Indices

Returning Property Names and Property Values