Solution to hard disk structure and hard disk errors

Hard Disk Structure

I. Physical Structure:
The hard disk consists of two parts: the first part and the control board.

(I) headers
The head disk refers to the head and disk. The headers include parts such as the disc, motor, and head. All parts are sealed in the shell, which is completely dust-free and vacuum. If you enable the shell, the hard disk will be voided. The disc is composed of one or more disc slices. Each disc is separated by a washer. The disc surface is extremely smooth and smooth, and coated with magnetic media. It is the carrier for recording data. Most of the disc is made of aluminum. ceramic products have appeared in the early days, and now glass materials have emerged. One disk corresponds to the upper and lower sides of the disk, and two heads respectively. The spindle motor drives the disc for high-speed rotation. because the disk is not in contact with the read/write data head during high-speed rotation, when the disk is close to the disk, even if there is a dust, the hard disk surface will be damaged, this is also the reason why computers do not shake at startup.
(Ii) Control Circuit Board
The control circuit board is welded to many chips, including the master control chip, data transmission chip, and high-speed data cache chip. The data on the disk is controlled by the Front read/write control circuit and the control circuit board.

Ii. Logical Structure:
The logical structure of hard disks is the division of data stored on disks. According to their different functions, there are five parts.
(I) MBR Main Boot Record)
The MBR is located on the disk's 0 track, 0 cylinder, and 1 slice. The size is 512 bytes. It consists of three parts: MBR (masterboot record), DPT (Disk Partition Table), and Boot Record ID. The MBR is the Master Boot Record, with 445 bytes at the point. The DPT is a partitioned table, which occupies 64 bytes. The Boot Record ID indicates that the boot zone mark occupies two bytes. Mbris generated by the partition program (such as fdisk.exe.
(Ii) DBR operating system boot zone (DOS Boot Record)
DBT is located in the disk's 0 track 1 cylindrical 1 sector, which includes a boot program and a local partition parameter record table called BPB (BiOS parameter block. DBR is generated by advanced formatting programs (such as format.com.
(3) FAT file allocation table (File Allocation Table)
(Iv) dir root directory)
The combination of fat and Dir is equivalent to the position of the point in the horizontal and vertical coordinates. It can precisely locate any file in the data area.
(V) Data Zone
The place where data is actually stored. In Windows, we can easily delete a file and then clear it from the recycle bin. In fact, this is only to clear the location information of the file and it still exists in the Data zone, this is also the basis for restoring data by the recovery Genie and recovery genie.

The image of this topic is as follows:

Use DEBUG to fix hard drive failure
First use a good hard disk
Start to DoS real-time mode, and then execute the DEBUG command C:/Windows/command/debug
Insert a blank floppy disk in the drive, and then type the following characters in the debug software environment:

-A 0100
Xxxxxx: 0100 XOR ax, ax
XXXX: 0102 PUSH AX
Xxxxxx: 0103 pop DS
XXXX: 0104 PUSH AX
Xxxxxx: 0105 pop es
XXXX: 0106 mov CX, 100
XXXX: 0109 mov BX, 7c 00
XXXX: 010c MoV word PTR [BX], 00
XXXX: 0110 Inc BX
XXXX: 0111 Inc BX
Xxxxxx: 0112 Loop 10c
XXXX: 0114 mov ax, 0301
XXXX: 0117 mov CX, 0001
XXXX: 011a MoV dx, 80
XXXX: 011d mov BX, 7c 00
XXXX: 0120 INT 13
XXXX: 0122 jmp ffff: 0000
XXXX: 0127
-W 100 0 0 1
-Q

At this time, the system will write a special boot information on this blank floppy disk, so that this special boot disk will be ready.

Finally, shut down the computer, replace it with the bad disk, connect it to the master disk, re-set all the hard disk parameters in bios, and set the system to start from disk, then restart the computer and insert the special boot disk into the soft drive. After about 10 seconds, the computer restarts automatically. At this time, I took out the special boot disk, insert the boot disk of Win98. After one minute, the system starts successfully. The familiar DOS prompt appears again. Then, re-partition the hard disk and reinstall Win98. At this point, all hard disk faults are eliminated.

Hard Disk troubleshooting

Last year, I introduced the dual-hard drive installation techniques in this column. If you are using the best solution, you have already tried it. However, many netizens and readers have encountered the following typical problems during the dual-disk installation process. Here we will introduce some corresponding solutions.

Dual-hard disk drive-character staggered solution

After the dual hard disk is installed, the reader will find that the drive C of the first hard disk (disk1) is still the drive C, but the drive D of disk1 is changed to the drive E in the new system, and the drive E is changed to the drive f... the drive C of the second hard disk (disk2) is changed to the drive D of the new system. The drive D of disk2 and the drive E are placed after all drive letters of disk1. In this case, the drive letter is staggered.

The dual hard disk drive character staggered problem is caused by MS-DOS on the hard disk management method. MS-DOS to the first physical hard disk activation DOS partition called C, the second physical hard disk effective activation DOS partition called D, the first physical hard disk extended DOS partition called E, F and so on, the remaining letters are allocated to the extended DOS partition of the second physical hard disk. If there is no second physical hard disk, or the second physical hard disk does not have a basic DOS partition, D is allocated to the first logical drive of the extended DOS partition of the first physical hard disk.

A series of problems may occur when the drive letter is staggered. The most common problem is that some software causes path errors due to drive letter changes. You need to re-confirm the file path when starting the software. To avoid drive-by-drive interruption, the simplest way for a Windows 95/98 system is to use its plug-and-play function. That is, in the bios, set the second hard disk to none. After the boot, the "plug-and-play" function of Windows 95/98 will prompt you to detect the new hardware and automatically assign the drive letter to it, at this time, the distribution of drive letters is consistent with the expectations of many people. Since the drive letters of all software on the original primary hard disk have not changed, the software on the hard disk can run as usual, and the problem of drive character crossover is solved.