public override void Close()
{
VerifyResult(_cco.Close());
_cco.DirectIOEvent -= (_IOPOSToneIndicatorEvents_DirectIOEventEventHandler)_cco_DirectIOEvent;
_cco.ErrorEvent -= (_IOPOSToneIndicatorEvents_ErrorEventEventHandler)_cco_ErrorEvent;
_cco.OutputCompleteEvent -= (_IOPOSToneIndicatorEvents_OutputCompleteEventEventHandler)_cco_OutputCompleteEvent;
_cco.StatusUpdateEvent -= (_IOPOSToneIndicatorEvents_StatusUpdateEventEventHandler)_cco_StatusUpdateEvent;
_cco = null;
}
