Shulou(Shulou.com)06/03 Report--

Before writing, I feel that this is like a prequel to an error code. when determining a hard disk failure (physical bad area or logical bad area), the first step is to have a hard disk physical examination, classify the damage category through the results of the physical examination, and then prescribe the right remedy according to the damage category.

Through the preliminary physical examination, two kinds of injuries were identified: hard injury and soft injury.

Let's start with the difference between hard disk damage.

Hard injuries such as head assembly damage, circuit damage, sector physical damage, etc.

Soft injury, bad logic track, system information error, track servo information error and so on.

1. For hard injuries, only part of them can be repaired.

Like a damaged magnetic head, it can be screened out by listening to the sound during the preliminary physical examination.

Reference example: hard disk detection listening case (1) hard disk detection listening case (2)

Comprehensive damage such as blisters, fires, etc., can be distinguished by the naked eye.

For physical sector damage, such as scratching and magnetic media weakening, tools such as PC3000 and EST Cloud repair are usually used for G-to-P repair.

two。 For soft injuries, common errors such as sector logic errors (bad logic tracks), system information errors and track servo information errors are basically repairable. Methods such as: low grid, DM software can quickly fix this kind of damage.

As for the error code of sector logic errors (bad logic paths), we have explained the hard disk sector structure, and students can connect and find it on it.

Then what factors will cause the logical bad way?

Let's first look at the relationship between the head assembly and the disk.

Encountered unexpected interference during disk writing, power outage, temperature, voltage instability, etc. When the voltage is unstable, the ADP system will produce a slight offset, so that the track of the read and write is not on the same track. If the deviation is small, the data will be slow, but the data will still be normal, but if the ADP is not normal, the data will be written biased, which will cause data damage and logical bad areas.

ADP:Adapter (Adapter)

It is used to control the current parameters clicked by the voice coil and to control the magnetic head assembly to move left and right, so that the data reading and writing of the read and write magnetic head can be carried out on the same track. It is also used to control the number of revolutions clicked, so that the flying height of the magnetic head can be controlled.

Logical bad area: if the ADP is incorrect, the read track will be inconsistent with the write track, and the track will become a logical bad area after write bias.

After understanding the logical bad area, we look back and see that the god horse is called the physical bad area, hence the name Siyi, which is essentially damaged, such as uneven magnetism and scratches, so what method will the factory use to carry out maintenance?

For head assembly damage, the factory will directly replace the head assembly, for circuit control damage, the factory will re-write the circuit IC. If the sector is physically damaged, rewrite the defect list, undergrid the interior, re-zero the track and sector, rewrite track servo information, sector information.

This part is only for the hard disk that is still under warranty, and the maintenance cost is very high for the hard disk that has expired the warranty period.

So there will be third-party hard disk maintenance tools.

In another reverse magnetization method, the software is used to generate the corresponding high and low level signal of the magnetic head from the magnetic medium itself, and the damaged sector is magnetized to regain the magnetic capacity of the damaged sector. But the damage to the head assembly is great.

When you come here, people will ask, "is it a hard drive defect list?" Why is everyone scrambling to get this modification list? In the next section, let's popularize science with you.

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