PURPOSE: To make a device small in size, light in weight and inexpensive by providing a one chip IC circuit integrated with an external interface for communication control, a recording/reproducing circuit and plural control circuits.

CONSTITUTION: An MCM(multi dip module) 42 is connected to the external interface 30 mounted on a small area printed board 43. By connection pieces 43a-i integrally molded on the outer periphery of the board 43, detection switches 24 for preventing the erroneous erase, detection switch 26 of the recorded capacity of a floppy disk 2, 00 sensor 27, a pair of magnetic heads 18, spindle motor 11, stepping motor 19, and automatic eject motor 31 are connected with the MCM 42. At this time, the connecting work is easily and rapidly executed since the connection pieces 43a-i are integrally molded on the outer periphery of the board 43, and the assembling work of the device is facilitated, then the improvement of productivity and the reduction of cost are accelerated.