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• Some properties are known in advance and will not change at run-time. Examples are positionUnits, or resolutionBest. These properties are implemented as regular (non-Dependent) properties, and are given default values directly in the properties block. In some cases, it may make sense to allow these properties to be optionally constructor-initialized, eg if their value depends on a firmware version which can vary from device to device. For the MP285, the positionUnits falls into this "set-it-and-forget-it" category.
• Some properties do change at runtime, and involve read-only queries to the hardware. An example is positionAbsoluteRaw. These properties are implemented as Dependent properties, with get-methods that send the appropriate query commands to the hardware.
• Some properties not only change at runtime, but can be set to new values, as well as queried. An example of such a property is velocity, implemented as a Dependent property with both a set-method and a get-method. The set-method sends the appropriate set-command (and value-to-be-set) to the hardware to set the value on the device.

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Minimal Required Implementation

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Other notes

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• In some cases, a property "does not apply" to a device. In the same vein, ScanImage does not utilize all available LSC properties. See #Minimal Implementation for ScanImage below.

At the current time, the abstract properties required for ScanImage operation are:

1. nonblockingMoveCompletedDetectionStrategy
2. positionAbsoluteRaw (get only)
3. isMoving (get only)
4. positionDeviceUnits (get only)
5. resolution (get only)

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