JPS57179915A - Data write-in system in external storage device - Google Patents

Abstract

PURPOSE:To increase the storage density and the capacity of recording medium of the same size, by assigning a different write-in level to each of input bit, encoding each bit and executing the encoding processing for all the input data. CONSTITUTION:A different write-in level (in this example, full and a half level, two levels in total) with each bit is assigned for encoding to each of a plurality of bits (in this example, two bits) in the order of an input bit signal. A shift register 1 inputs a write-in data Dw to a write-in level designation circuit 2 at each two bits in the order of input bit. This designation circuit 2 designates the write-in level to each bit. Through this designation, a write-in current generating circuit 3 generates a write-in current I2, which is generated for a full level I2F and a half level I2H in accordance with the bits and recorded with heads 4, 5,- n. Thus, recording is made with double density as conventional systems.