JPH04114368A - Alternate processing method for fixed disk device - Google Patents

Abstract

PURPOSE:To shorten rotation latency time by performing recording and reproduction on a sector in an alternate area nearest to a defective sector by switching a head to the alternate area when a defect occurs in the sector in a user area. CONSTITUTION:A CPU 3 records data on the null area of the user area A in a fixed disk 1 by controlling the head 2 via a recording and reproducing mechanism 6, and after that, reproduces recording data and stores it in a RAM 5. When abnormality is detected in reproduced data, the head is switched, and the recording is performed on the alternate area nearest to the sector that fails in the recording, thereby, it is possible to shorten the rotation latency time when the defect occurs in the sector in the write with verification of one sector.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a replacement processing method for a fixed disk device used as an external storage device of a computer or the like.

2. Description of the Related Art In general, a recording medium such as a fixed disk device has a recording area composed of concentric tracks, and the tracks are divided into a plurality of sectors in the circumferential direction. A fixed disk is made up of a plurality of disk-shaped media stacked on the same rotating shaft, and a head for recording and reproducing information faces each medium surface.

When recording and reproducing, when the recording and reproducing of one track on the same cylinder (a collection of all tracks located at the same distance from the rotation axis) is completed, the head is switched and the next track is recorded and reproduced. Recording and playback is performed in units.

With this type of recording medium, there are sectors that cannot be recorded or played back due to manufacturing defects or defects that occur during use, so if data is not recorded correctly in the user area where the user directly writes data. In consideration of this, in addition to the user area, there is an alternate area in which the same data is recorded again. Such a write function is called a write function with verify. The user area and alternate area are fixed in advance depending on the recording medium.

Write processing with verification in conventional fixed disk devices records data in a free space in the user area of a recording medium, and checks whether or not the address can be detected when reproducing the data immediately after that, and whether the ECC (ECC) of the reproduced data is detected. Verification is performed depending on whether an abnormality in the error correction code (error correction code) can be detected. As a result, if data cannot be recorded correctly in the user area, switch the head to the alternate area, search for empty sectors in order from the first sector of the alternate area, record the same data in that sector, play it back, and verify. and confirms that it has been correctly recorded in the substitution area. If the data is not recorded correctly, write processing with self-verification is executed as long as there is a free area in the replacement area.

With such a replacement processing method, even if a defective sector occurs in the recording medium due to a manufacturing defect or a defect occurring during use, data can be recorded and reproduced correctly.

Problems to be Solved by the Invention However, in the above conventional replacement processing method, for example, 1
Write with sector verification is performed, and if recording cannot be performed correctly, the head is switched to the alternate area and the write is performed by searching for an empty sector from the first sector.
There was a problem in that rotation waiting time occurred. Further, a similar problem occurs when a defect occurs in the last sector of continuous write or read with verification.

For example, as shown in FIG. 4, if sector 0 of the O-th head in user area A is a non-recordable sector, the data in sector 0 in replacement area B will be recorded and reproduced because the medium is rotating. In order to do so, there will be a wait for one rotation.

SUMMARY OF THE INVENTION The present invention is intended to solve these conventional problems, and aims to provide a replacement processing method for fixed disk drives that can reduce rotational waiting time to a minimum.

Means for Solving the Problems In order to achieve the above object, the present invention performs write processing with verify, and if the recording cannot be performed correctly, the head is switched to a replacement area, and the head is switched to a replacement area to have an address of the defective sector address + α. The same data is recorded and reproduced in empty sectors after the sector (α≧1).

Here, α is the number of sectors corresponding to track skew and program processing time.

Therefore, according to the present invention, when there is a sector defect in the user area in one-sector verified write and continuous verified write or read processing, the head is switched to the replacement area and the replacement area closest to the defective sector is Since recording and reproduction are performed in the same sector, the conventional system has the advantage that the wasteful rotation waiting time can be reduced to a minimum.

Embodiment Hereinafter, an embodiment of the present invention will be described with reference to the drawings. FIG. 1 is a schematic block diagram of a fixed disk device according to the present invention, and FIG. 2 is a developed view of one cylinder of the fixed disk.

In FIG. 1, reference numeral 1 denotes a fixed disk, in which a plurality of disk-shaped media are coaxially stacked on a single rotating shaft. The recording area of each medium is composed of concentric tracks, which are divided into a plurality of sectors in the circumferential direction. , has a replacement area B in which the same data is recorded again if data is not correctly recorded in the user area A.

Reference numeral 2 denotes a head for recording and reproducing data on the fixed disk 1. Each head is disposed facing each other on the same cylinder on each medium surface, and is driven in the radial direction as a whole. 3 is a CPU that controls data recording and reproduction.

4 is a ROM in which the execution program of CPU 3 is stored.
5 is a RAM having an area where recording/reproduction data is temporarily stored and other work areas for the CPU 3.
It is. Reference numeral 6 denotes a recording/reproducing mechanism having a recording/reproducing head 2, a mechanism for moving the head 2, a mechanism for rotating the medium, and the like.

Next, the operation of the above embodiment will be explained. CPU3 is
By controlling the head 2 through the recording/reproducing mechanism 6, data is recorded in a free area of the user area A of the fixed disk 1, and then the recorded data is reproduced and stored in the RAM 5. The reproduced data is subjected to an FCC (error correction code) and verified depending on whether an abnormality is detected. If there is no abnormality in the recorded data, it is assumed that the recording was performed correctly and the operation is normally terminated.

If an abnormality is detected, for example, as shown in Figure 3, if the first head in user area A fails to record in sector 4, the mth head in replacement area B will switch to the mth head in replacement area B and record the data in sector 4 where recording failed. a is recorded in sector 5 (after the sector where recording failed +α) in replacement area B that is closest to sector 4. Similarly, if recording fails in sector 1 of the third head, data b is recorded in sector 2 of alternate area B.

As described above, according to the above embodiment, it is possible to minimize the rotational wait time when a certain sector in one sector write with verify is defective, and when the last sector of continuous write or read with verify is defective. It has the advantage of being able to

As described in detail, the present invention enables one-track write with verification and continuous verification by recording incorrectly recorded data in the defective sector+α of the replacement area or in the empty sector after that. This has the effect of shortening the rotational waiting time when writing or reading data.

[Brief explanation of the drawing]

FIG. 1 is a schematic block diagram of a fixed disk device according to the present invention, FIG. 2 is a developed view of one cylinder of the fixed disk, and FIG. 3 is a developed view of one cylinder for explaining the replacement processing method of the present invention. FIG. 4 is a developed view of one cylinder for explaining the conventional replacement processing method. 1... Fixed disk, 2... Head, 3... CP
U. 4...ROM, 5...RAM, 6...recording and reproducing mechanism, A...user area, B...alternative area, a.
b...Data. Name of agent Patent attorney Akira Okaji and two others Figure 1 Prisoner Figure 3

Claims (1)

[Claims] Immediately after data is recorded in the user area of a recording medium, if the recorded data is not reproduced correctly and the same data is recorded in a replacement area of the recording medium, the defective sector address must be at least equivalent to the head switching time and program processing time. A replacement processing method for a fixed disk device in which the same data is recorded in a sector in a replacement area of a sector address that is the sum of the number of sectors.