Write-data signal compensation apparatus for disk storage

A disk storage for operating in combination with a controller, said disc storage comprising

• a disc having a plurality of tracks thereon, at least some of said tracks being compensated;
• at least one read-write head, said head being movable radially with respect to said disc;
• a read-write circuit connected to said read-write head, said read-write circuit generating at a read terminal a read signal of data patterns for coupling to said controller, said controller generating a first write signal in response to said read signal;
• write signal compensation means including a plurality of write signal compensation circuits, each of said write signal compensation circuits providing a different compensation amount, for converting said first write signal into a second write signal, each of said write compensation circuits having an input to which said first write signal is applied and an output from which said second write signal is produced, each of said write compensation circuits changing transition points of pulses of said first write signal so as to compensate pulse widths of the pulses of said first write signal by predetermined amounts to obtain said second write signal, pulse rates of the pulses of said first write signal and said second write signal being maintained at the same rate;
• compensation amount switching means coupled to said write signal compensation means for switching a selected write signal compensation circuit to a write terminal of said read-write circuit, said read-write circuit thereby receiving said second write signal;
• and
• compensation amount selecting means coupled to said compensation amount switching means for generating a signal selecting one of said plurality of write signal compensation circuits in accordance with the radial position of said read-write head on said disk.