Disk storage is an external storage device that uses disks as storage media. Disk storage is an auxiliary memory that uses magnetic recording technology to store data on a rotating disk coated with magnetic recording media. It has the characteristics of large storage capacity, high data transmission rate, and long-term storage of stored data.
The operating environment of this tutorial: Windows 7 system, Dell G3 computer.
Disk storage is an external storage device that uses disks as storage media.
Disk storage (magnetic disk storage) is a memory that uses disk as the storage medium. It is an auxiliary memory (external memory) that uses magnetic recording technology to store data on a rotating disc coated with magnetic recording media. It has the characteristics of large storage capacity, high data transmission rate, and long-term storage of stored data.
Disk storage is an auxiliary storage that uses magnetic recording technology to store data on rotating disk media. This is a widely used direct access memory. Its capacity is hundreds of times larger than that of main memory. In computer systems of various sizes, it is often used to store operating systems, programs and data, and is an expansion of main memory. Data stored in disk storage can be stored for a long time. Compared with other auxiliary storage, disk storage has larger storage capacity and faster data transfer rate. A typical disk drive includes a disk spindle rotating mechanism and drive motor, a head arm and a head arm bracket, a head arm drive motor, a purification disk cavity and an air purification mechanism, a write and read circuit, a servo positioning circuit and a control logic circuit.
The disk rotates at a constant speed. The head block (floating head) with a floating surface suspended on the head arm is pressed against the disk surface by the force of the loaded spring, and the air flow driven by the disk surface floats the head block. Maintain a stable small gap between the head block and the platter. The air filtered by the dust filter is continuously sent into the disc cavity to keep the disc and head block in a highly purified environment to prevent scratches on the head block and disc surface. According to the track address (ie cylindrical surface address) and seek command sent by the controller, the positioning circuit drives the linear motor to move the head arm to the target track. The servo head reads the servo track signal and feeds it back to the positioning circuit, so that the head arm follows the servo track and stabilizes on the target track. The read-write and head selection circuit connects the selected magnetic head according to the magnetic head address sent by the controller, and records the data sent by the controller bit by bit on the target track in a serial manner; or conversely, reads from the selected track data and sent to the controller. The head and arms are mounted on the comb trolley, and all head and arms move together during path seeking. All the concentric circular tracks with the same diameter on the data surface are collectively called the cylindrical surface, that is, all the tracks that can be accessed by the head arm positioning at one time. Each track is recorded in a fixed format. After the index marking the start of the track, the track's address (cylinder number and head number), the condition of the track and other reference information are recorded. The error correction code of the segment is appended to the end of each recording segment. Errors caused by a few consecutive permanent defects are corrected by the error correction code. Tracks with multiple permanent defects must be replaced with spare tracks. Write and read operations are performed in units of record segments. There are two types of recording segment lengths: fixed segment length and variable segment length.
In computer systems, disk storage is often used to store operating systems, programs and data, and is an expansion of main memory. The development trend is to increase storage capacity, increase data transmission rate, reduce access time, and strive to be light, thin, short, and small. Disk storage usually consists of a disk, a disk drive (or disk drive), and a disk controller.
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