What is Gigabyte SATA?

SATA (Serial ATA) hard disk, also known as serial hard disk, is the future trend of PC hard disks, which has basically replaced traditional PATA hard disks. The full name of SATA is Serial Advanced Technology Attachment. The Serial ATA committee composed of Intel, APT, Dell, IBM, Seagate and Maxtor officially established the Serial ATA 1.0 specification. In 2002, although the related equipment of Serial ATA is still Not officially listed, but the Serial ATA committee has preemptively established the Serial ATA 2.0 specification. Serial ATA uses a serial connection method. The Serial ATA bus uses an embedded clock signal and has stronger error correction capabilities. Compared with the past, the biggest difference is that it can check the transmission instructions (not just data). Errors are automatically corrected when found, which greatly improves the reliability of data transmission. The serial interface also has the advantages of simple structure and hot plug support.

SATA, Serial ATA (Serial ATA), the full name is Serial Advanced Technology Attachment, was jointly proposed by companies such as Intel, IBM, Maxtor and Seagate

Each SATA hard disk storage node is composed of a memory control interface MCI and a SATA hard disk controller, as shown in Figure 1. Among them, MCI is responsible for generating, encapsulating or decapsulating message packets according to the message frame format, and extracting and parsing operation commands for accessing storage nodes based on the received message packets, including

Traditional Parallel ATA uses single-end-signal-amplified-system, a single-mode signal amplification system. In this system, the noise will be transmitted and amplified along with the normal signal, and it is not easy to be suppressed. It is especially serious at high speeds. In order to effectively reduce the noise interference, we have to use a voltage of up to 5V to transmit the positive-constant signal, so that Normal signals with large voltages overwhelm noise signals with small voltages. Although a large voltage can effectively suppress noise, a large voltage also indicates

version	bandwidth	speed	Maximum data cable length
SATA 3.0	6Gb / s	600MB / s	2 meters
SATA 2.0	3Gb / s	300MB / s	1.5 m
SATA 1.0	1.5Gb / s	150MB / s	1 meter
PATA	1Gb / s	133MB / s	0.5 m

Hard disks, as external storage for personal computers and various servers, have occupied an important position in the storage field since its birth. The first hard drive in human history was produced by IBM in 1956, with a capacity of only 5MB, and almost the size of two refrigerators. The capacity of a single disk can reach several TB, and the volume is only the size of a small box. Hard disks can be divided into mechanical hard disks and solid-state hard disks. Mechanical hard disks use magnetic media and solid-state hard disks use semiconductor storage media. Mechanical hard disks have complex structures consisting of magnetic heads, disks, and motors. The internal structure of solid-state hard disks is relatively simple, mainly Packaged by semiconductor flash memory chips. Early hard disks were mechanical hard disks. Their physical structure includes magnetic heads, tracks, sectors, and cylinders. Although there is no physical structure for solid-state hard disks, the interface protocol is the same as that of mechanical hard disks, and it will be borrowed when describing. Cylinder, sector and other concepts. The magnetic head is the most expensive part of the hard disk, and it is also the most important and critical part of the hard disk. The traditional magnetic head is a read-write electromagnetic induction magnetic head. The hard disk read and write are two different operations. This two-in-one magnetic head must be designed with both read and write characteristics at the same time. Limitations in hard drive design. Hard disks generally use MR magnetic heads (Magneto resistive heads), which use a separate magnetic head structure: the write head still uses the traditional magnetic induction head, and the read head uses the new MR head. The different characteristics are optimized separately to get the best read / write performance. In addition, the MR head senses the signal amplitude through resistance changes rather than current changes, and the accuracy of the read data is improved accordingly. And because the amplitude of the read signal is independent of the track width, the track can be made very narrow, thereby increasing the disc density.

When the magnetic disk rotates, if the magnetic head stays in one position, each magnetic head will draw a circular track on the surface of the magnetic disk. These circular tracks are called tracks. Tracks are magnetized areas that are magnetized in a special way on the disk surface. Information on the disk is stored along such tracks. Adjacent tracks are not close to each other, because the magnetism will affect each other when the magnetizing units are too close to each other, making it difficult to read and write the magnetic head.

Each track on the disk is divided into several arcs. These arcs are sectors of the disk. Each sector can store 512 bytes of information. When reading and writing data to the disk, Sector is the unit. That is, the minimum amount of data to read and write is 512 bytes. ^[3]

Hard disks usually consist of a set of overlapping disks. Each disk surface is divided into equal numbers of tracks, and numbers are numbered starting from "0" on the outer edge. Tracks with the same number form a cylinder, called the cylinder surface of the disk. . The number of cylinders on a disk is equal to the number of tracks on one side of a disk. Whether it is a dual-disk surface or a single-disk surface, since each disk surface has its own magnetic head, the number of disk surfaces is equal to the total number of magnetic heads. Therefore, the total capacity of a hard disk is:

Storage capacity = number of heads x number of tracks (cylinder) x number of sectors per track x number of bytes per sector (512 B)