Abstract: A magnetic tape unit includes a magnetic tape provided with a plurality of tracks, a magnetic head for writing or reading data from the tape, a position determiner for monitoring the relative position between the tape and the head, and a position compensator for adjusting this relative position. The monitoring by the position determiner is performed based on signals read out from the servo control tracks of the tape. The position compensator keeps the magnetic head and tape in proper positional relation based on the results of the monitoring by the position determiner.

Abstract: A pseudo-LSI device for emulating a single electronic circuit using a plurality of programmable logic elements mounted on a common circuit board, providing a pseudo-operation unit comprising a plurality of programmable gate arrays constituting a pseudo-LSI when having circuit data written thereto, a nonvolatile memory unit for storing the circuit data to be downloaded from outside, a transfer unit for transferring the circuit data stored in the nonvolatile memory unit to the pseudo-operation unit, and a power supply unit, said four units being provided in the form of an assembly, which can be used in developing LSIs and to debugging systems.