Sets or returns the current filter wheel position

Namespace: ASCOM.DeviceInterface
Assembly: ASCOM.DeviceInterfaces (in ASCOM.DeviceInterfaces.dll) Version: 6.0.0.0 (6.1.1.2619)

Syntax

C#
short Position { get; set; }
Visual Basic
Property Position As Short
	Get
	Set
Visual C++
property short Position {
	short get ();
	void set (short value);
}

Remarks

Must be implemented, must not throw a PropertyNotImplementedException.

Write a position number between 0 and N-1, where N is the number of filter slots (see Names). Starts filter wheel rotation immediately when written. Reading the property gives current slot number (if wheel stationary) or -1 if wheel is moving.

Returning a position of -1 is mandatory while the filter wheel is in motion; valid slot numbers must not be reported back while the filter wheel is rotating past filter positions.

Note

Some filter wheels are built into the camera (one driver, two interfaces). Some cameras may not actually rotate the wheel until the exposure is triggered. In this case, the written value is available immediately as the read value, and -1 is never produced.

Exceptions

ExceptionCondition
InvalidValueExceptionMust throw an InvalidValueException if an invalid position is set
NotConnectedExceptionMust throw an exception if the Filter Wheel is not connected

See Also