MAGNETIC DISK DEVICE AND A CONTROLLING METHOD THEREOF, PARTICULARLY WITH REGARDS TO EXPANDING AN INFORMATION STORAGE CAPACITY WHEN AN ENVIRONMENT IS FAVORABLE TO THE MAGNETIC DISK DEVICE

摘要

PURPOSE: A magnetic disk device and a controlling method thereof are provided to decide whether an external environment is favorable by a function of reading reference signals stored in predetermined areas of a temperature sensor, an air pressure sensor, and a medium, thereby expanding an information storage capacity when the external environment is favorable to the device. CONSTITUTION: A host transmits a write command to a hard disk controller(501). A magnetic disk device converts a logic address into a physical address before seeking a magnetic head in a target sector(503), and attempts whether a writing function is available(505). If so, the device writes data in a write limit area(507), and checks whether a next command is transmitted from the host(509). If not, the device completes the writing function.