Abstract: A data storage system having a plurality of parallel magnetic tape tracks. Error protection is based on a frame-wise product code having first code words distributed over a single track and second code words distributed cyclically among all tracks. In a read mode the system drives the tape in a first closed servo loop synchronized by the data rate, and in a write mode in a second open loop operating at a preset tape speed. The tape driver has a bidirectional buffer for framewise buffering data between the tape and an output, while interchangeably presenting either an amble frame (synchronizing patterns) or a data frame to the tape. The system enables handling of data framewise bidirectionally by the tape driver. A third layer of error protection is provided by a Reed-Solomon code operating on a uniform symbol series across a plurality of successive frames without reference to the amble frames, and assignment of all redundant symbols thereby produced to exclusive-redundancy frames.