Patent US 4,054,947

An interface for coupling a computer to a plurality of magnetic tape transports, including dual-density transports and combinations of high and low density transports. The interface includes an automatic density selector for detecting the density of data stored on a tape prior to reading and for storing this information for as long as the tape is being used. A read-only memory and other logic circuitry translate computer operating commands into commands readable by a transport formatter. The interface also couples digital data between the computer and the formatter and converts formatter status information into language readable by the computer.