A disk drive system includes a control bus, a processor and a controller attached to the control bus. To this end, in the fluid cylinder, a flow passage leading to a chamber at the rod side of the cylinder is provided inside a rod, and a pin hole in a rod front end portion and a pin fitted in the pin hole are formed into a swivel joint so that the flow passage is always guided to an outside even if the pin hole and the pin are relatively rotated. An etch barrier film and an insulating film are sequentially formed after the formation of the storage node contact plug. However for an active call, no air-time charges are incurred as the user transitions between the cellularDPCS environment and the neighborhood or local cordless service environment.