Two-module-read, read-after-write, bi-directional tape drive

Abstract

A digital tape drive wherein tape is written, and a read-after-write operation is immediately performed to check the integrity of the write operation, for either direction of tape movement. The tape contains a plurality of parallel data tracks. Two read/write head modules span the entire tape. The read and write gaps of each module are alternately spaced across the width of the tape, such that the write gaps of one module are aligned with the read gaps of the other module. When one module is selected for writing, as a function of the direction of tape movement, the other module is selected to read-after-write check the first module's written data. One module writes odd-track data during one direction of tape movement, and reads even-track data during the opposite direction of tape movement; as the other module writes even-track data during said opposite movement direction, and reads odd-track data during said one movement direction. Common read and write eletronic circuits are switched between the two modules, since each module is using only one of its read and write gap multiples at any given time.