hard disk low-level formatted function hard disk low-grid formatting is the most thorough initialization method for the hard disk, after the low-level hard disk, the original protected data will be lost, so generally In the case of low-level hard drives, it is highly undesirable, and it is only necessary to lower the hard disk. There are two kinds of so-called necessary time. First, the hard disk factory will perform a low-level format on the hard disk before leaving the factory. The other is that when the hard disk has some type of bad sectors, the low-level format can play a certain role. Relieve or shield. For the first case, there is no need to say more here, because the low-level work of the hard disk before leaving the factory is only accessible to the hard disk engineers. For ordinary users, there is no need to consider this. As for the second case, what type of bad sectors need low levels? Before explaining this critical issue, let's take a look at the type of bad sectors on the hard drive. In general, bad sectors can be divided into physical bad sectors and logical bad sectors. Among them, the logical bad sectors are relatively easy to solve, which means that the hard disk is subjected to long-term interference during writing, resulting in an ECC error. In terms of process, it means that when the hard disk writes data, it will recombine the data with the logic of ECC. Generally, the operating system needs to write 512 bytes, but in fact the hard disk will write dozens of bytes more, and All of these bytes are checked and encoded by ECC. If the ECC correction code calculated by the original byte is different from the ECC calculated by the read byte, an ECC error will occur, which is the cause of the so-called physical bad sectors. As for the physical bad sectors, it is more deadly to the damage of the hard disk. It also has the difference between soft and hard physical bad sectors. The physical damage of the disk surface is hard, which cannot be repaired. If the data is written incorrectly due to external influences, the system will also consider it a physical bad track. This physical bad track can be repaired by using some hard disk tools (such as the detection and repair software provided by the hard disk manufacturer). Tiny hard disk surface damage, some hard disk tools (such as Western Digital Data Lifeguard Tools) can be redirected to a good reserved sector to correct the error. For these bad sectors, the hard physical bad sectors must not be repaired. It is the most direct damage to the hard disk surface, so even if it is low-level or using hard disk tools, it can't be repaired (unless it is very small damage, Some tools can retain this part of the bad track without using it to achieve the purpose of the solution). For logical bad sectors or soft physical bad sectors on the hard disk, users can try to use low-level formatting to achieve the role of shielding bad sectors, but it should be pointed out here that shielding bad sectors does not mean eliminating bad sectors. All the partitions in the original hard disk are deleted, but the bad sectors still exist. The shielding only hides the bad sectors and prevents the users from using these bad sectors when storing data, so that the reliability of the user data can be guaranteed to a certain extent, but Bad sectors will spread as hard disk partitions and formatting times increase. Therefore, the author does not recommend the user to low-level hard disk, how to repair the hard disk during the warranty period or find a replacement for the dealer, it can be said that the best solution, but also the most thorough solution. If the hard disk does not change after the warranty period, you can try a low-level hard disk to prevent data loss caused by storing data to bad sectors. For how to make a low-level hard disk, it is generally operated using a low-level tool. This will be described in detail in the following sections. Here are some related topics. That is, the low-grid tool and the hard disk detection tool are essentially different. The low-grid tool is a low-level function for the hard disk, and the hard disk detection tool is generally used by the hard disk manufacturer to detect the hard disk, and early to find the hard disk error to remind The user backs up important data or repairs the hard disk. It is not used for low-level hard disks. Low-level formatting with Debug assembly language
Low-level formatted hard disk can complete the destruction of data in the hard disk, so be careful before operation. There are many ways to lower the hard disk, such as low-level hard disk in CMOS, or use the assembly language for low-level hard disk, and the most common is to use some tools to low-level the hard disk, common low-grid tools have lformat , DM and hard drive manufacturers have introduced a variety of hard disk tools. Assembler is a relatively low-level programming language. It is very convenient to directly operate the hardware, and it is very efficient. If the software system needs to directly operate the hardware, the assembly language is often used. The assembly can also be used for low-level formatting of the hard disk. It is more flexible than tools such as DM. The specific application is to use the debug program, and the specific operation is to call the low-level formatter stored in BiOS in the debug environment ( The direct low-level hard disk in CMOS is also called this low-level program). There are usually three implementation methods: (1) Directly calling the low-level program in BiOS ROM. The low-level program is stored in the BiOS ROM of many computers. The storage address starts from the C8005H address. The specific operations are as follows: A:\\>Debug -G C800 : 0005 (//screen display information (different versions of BiOS display information may be different), after the carriage return prompt :) Current Interleave is 3 select new interleave or Return for current (//this is asking the user to choose Cross factor, press Enter to take the default value of 3. You can also enter a new cross factor value. The cross factor of the hard disk is usually 3, so you can press Enter. The screen then prompts:) Are you dynamically configuring the drive-answer Y /N t Press "Y" to begin formatting the drive C: with interleave 03 (//type "Y" to start low-level hard disk) Formatting ... (//ask if you are dealing with bad tracks after completion) Do you want to Format bad track-answer Y/N? If not, answer with "N". The screen displays: Format Successful, system will new restart, Insert DOS diskette indrive A: Insert the system disk to the A drive, you can perform partitioning, advanced formatting and other operations to install the system. (2) The low-level operation of the hard disk is performed by calling the function No. 7 of the INT 13H interrupt as follows: A:\\>DEBUG -A 100 -XXXX:0100 MOV AX,0703; (//cross factor is 3) -XXXX:0103 MOV CX, 0001; (//0 track 0 sector) -XXXX: 0106 MOV DX, 0080; (//C disk 0 track) -XXXX: 0109 INT 13 -XXXX: 010B INT 3 -XXXX: 010D -G 100 so the hard drive is low. (3), call the INT 13H interrupt function No. 5 to call the INT 13H interrupt on the hard disk No. 5 function only low grid 0 side 0 channel 1 sector, without having to lower the entire hard disk, so that the low grid in a very short time carry out. The specific operations are as follows: A:>DEBUG -A 100 -XXXX:0100 MOV AX,0500; (//call function No. 5) -XXXX:0103 MOV BX,0180; (//set buffer address) -XXXX:0106 MOV CX, 0001; (//0 track 1 sector) -XXXX: 0109 MOV DX, 0080; (//C disk 0 track) -XXXX: 010B INT 13 -XXXX: 010D INT 3 -E 0180 0 0 0002 (//write parameters) -G 100 Low-level formatting with DM The full name of the DM is Hard Disk Management Program, which can perform low-level formatting and verification of the hard disk, which can improve the efficiency of the hard disk. In general, DM has the following functions: low-level hard disk formatting, partitioning, advanced formatting, hard disk parameter configuration, and other functions. In practical applications, the dm tool is the same as a normal DOS command (such as fdisk or format). Its command format is: A:>DM [parameter]. The parameters can take the following values: <> /M DM software enters manually. If there is no such parameter, DM runs automatically, and then executes INITIALIZE. PARTITIONG. PREPARAFION. <> /C DM software is executed in color, ie on a color display. <> /P DM software manages hard disks in PC/XT mode. <> /A DM software manages the hard disk in PC/AT mode. <> /2 DOS 2.XX version mode. <> /3 DOS 3.XX version mode. <> /4 DOS 4.XX version mode (only for DM 5.01 version). <> /V DM runs in a way that changes the cluster length and root directory entries. In actual use, the following two methods are commonly used: 1. A: > DM (automatic mode. When initializing the hard disk, many parameters use the default value and almost no manual intervention). 2, A: > DM (manual mode. Some parameters should be specified manually when formatting). After starting the dm tool, the user can select the corresponding operation according to his own needs. Since it is also stored in the form of a DOS user interface, it is also very simple and clear to use. Other low-level formatting methods In addition to the two low-level tools described above, there are many other low-level formatting methods. 1. Direct operation in CMOS
If the motherboard supports, the user can directly format the hard disk in CMOS. This method is very simple and convenient, so if possible, I recommend using this method to make the hard disk low. Specific operation method: Enter CMOS Setup according to the system prompt when booting (if it is Forward, such as BiOS, you will be prompted to press DEL to enter CMOS Setup, if it is Intel motherboard, press F2 to enter CMOS Setup), then select low formatted in CMOS menu. HardDisk Drive selects, then according to the program prompts to wait for the low-level hard disk, and answer some program questions to perform low-level formatting of the hard disk. 2, lformat.com program low-level hard disk In addition to dm tools, there is a more common low-level program is lformat.exe, which is a low-level format hard disk tool introduced by Maxtor. After running lformat.exe in DOS state, the program will start the warning interface shown in Figure 3-3-43. The general meaning explained in this screen is that if the user uses this tool, all data in the hard disk will be lost, so it is recommended to back up the necessary data before running it, and recommend removing all other hard disks. If the user forgets to back up the data and wants to quit the program, he can press any key other than Y. If the user confirms that the hard disk is low, press the "Y" key. If "Y" is selected, the program will ask the user to select the hard disk or low-level the current hard disk. Then, after asking a few questions, the low-level formatting process of the hard disk can be started.