Abstract: A key-depression data input device for detecting a depressed key in a plurality of keys arranged in a key matrix, the device including phantom key detection unit for detecting an occurrence of phantom key state, andkey release checking circuit for checking a released key among depressed keys, the releasing of the released key causing a cancellation of the phantom key state. Code data corresponding to the depressed keys being generated and delivered when the key release checking circuit detects that the released key is the key satisfying a predetermined depression-release sequence condition and an error warning being delivered when the key release checking circuit detects that the released key is not the key satisfying the predetermined depression-release sequence condition.

Abstract: A holder in which a bubble cassette housing a bubble memory device is inserted. The contacts of the holder contact the contacts of the cassette when the cassette is inserted into the holder, so that current can flow into the bubble memory device. The holder contains a detector for detecting the insertion and withdrawal of the cassette. A circuit controls the current introduced into the magnetic-bubble memory device so that the current is introduced after the contacts of the cassette and the contacts of the holder are connected and is interrupted before the contacts of the cassette and the contacts of the holder are disconnected.

Abstract: An electrical connecting device where electrical terminals are connected between two connector units by inserting the first connector unit into an insertion mouth of the second connector unit. Moreover, the electrical terminals of both units come into pressure contact by inserting the first connector unit into the second connector unit and then rotating the first connector unit in the direction almost at a right angle to the inserting direction. Such a structure is highly adaptable to an electrical connecting device where the first connector unit comprises a magnetic bubble memory unit, while the second connector unit comprises a holder unit for accommodating the bubble memory unit. This device realizes a stable and reliable electrical connection between both units with an excellent operability for insertion.