JPS60129976A - Substituting system of storage information - Google Patents

Abstract

PURPOSE:To prevent destruction of storage information in advance by performing the decision of failed storage information even at the normal end of processing. CONSTITUTION:A retrial frequency storage area ra is expanded newly in the constitution of an ID section of a magnetic disc. When the system judges no error, the retrial frequency N' stored before the area ra on a sector is read and stored in a memory of a control section 1. Then whether or not the present retrial frequency N and the preceding frequency N' are larger than B (B<A) is discriminated. When it is judged that the both are larger than the B, the substituting processing is performed and when the N and N' are smaller than the B, the data stored in the area ra of the sector is revised into the present retrial frequency N and the processing is finished. In short, before storage information is defective, the storage information is preserved.

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field] The present invention relates to a storage information replacement method for re-registering storage information such as a defective sector formed in a magnetic disk device or the like in a replacement area.

[Prior Art] Generally, the format of information stored on a magnetic disk or the like is as shown in FIG. 1A, and the data section, which is the information section, is composed of an ID section and a data section. As shown in Fig. 1, this ID part contains address information of the sector, such as cylinder, head, sector, and an alternative flag that turns ON when the sector is a defective sector.Alternative destination that is valid only when the alternative flag is ON. It has areas for the replacement destination cylinder, head, and sector, which are the address information for each.

The process of accessing a magnetic disk with such a configuration is described in the third section.
To explain with reference to the figure, in step S1, it is determined whether or not an error has occurred in step S2 following reading (Read) or writing (Write). If there is an error, the number of tries N is set in step S3.
Then, it is determined in step S4 whether this count value N is greater than a pre-added number A, and if N<A, another attempt is made and the process returns to step S1. If N<A, alternative processing is performed in step S5.

By the way, with such an ID structure, for example, if sector A is determined to be a defective sector, even if sector A was accompanied by l-rai operation every time it was accessed in the past, it is irrelevant to the determination of the defective sector. Defective sectors are determined based on the results of current accesses. Since the read data and the contents of the data section do not match at the time it is determined to be a defective sector, the contents of the data section of sector A are usually not guaranteed even if alternative processing is performed. . In other words, the sector A does not have historical information about the number of times it is accessed.
Even in the case where there is a high possibility that the sector will become a defective sector in the future due to the repeated try operation, it is impossible to protect the data before it is determined to be a defective sector.

[Purpose] The present invention provides an area for storing a part of the stored information when the number of access attempts exceeds a certain determination level;
When the number of retry attempts exceeds the judgment level in the next access, alternative processing is executed to save the stored information before it becomes defective, thereby eliminating the drawbacks of the conventional method. be.

[Explanation of Examples] Embodiments of the present invention will be described below with reference to the drawings.

The magnetic disk device to which the present invention is applied has a configuration as shown in Fig.
A magnetic head 2 for reading data (R) is provided, and sector substitution processing is performed by a control section 1 that performs control operations as shown in FIG.

The configuration of the magnetic disk (not necessarily limited to a disk or magnetic, but may be any other type of writable storage medium) is the same as in Figure 1A, but the configuration of the 1D section is the same as in Figure 1A. Unlike the configuration shown in FIG. 1B, it has the configuration shown in FIG. 2, and consists of a newly added retry count storage area ra [7]. Access to a sector as shown in FIG. 2 is performed as shown in FIG. Note that steps indicated by the same symbols as in FIG. 3 perform the same operations as in FIG. 3.

In FIG. 4, if it is determined in step S2 that there is no error, the process proceeds to step S6, where data is recorded before the area ra on the sector, or the number of tries N' is read out and stored in the memory on the control unit 1.

Next, in step S7, it is determined whether the current number of climbing attempts N, and the number N' are larger than B (B<A).

If it is determined that both are larger than B, the process advances to step S5 to perform alternative processing, and if it is determined that N and N' are smaller than B, the data stored in the sector area ra is updated to the current number of retries N, and the process ends. do. In short, a certain sector can be successfully read/written within A number of attempts (N) at which it reaches the defective sector determination level.
e, if the number of tries N is in the relationship A>H, and N<B, then the number of tries is I.
It ends normally without leaving any li history. It is N23,
If the forward I/lie number N' in Fig. 2 is N x B, then
Write the number of glue attempts this time N in the ID section
and the normal end is N23, and the N' is NI.
If it is B, the sector has been retried N times in the past with the relationship B≦N<A, and there is a high possibility that it will become a defective sector if it is repeatedly accessed in the future, so the sector is considered a defective sector. Perform alternative processing. At this time,
Since the data portion contents of the sector are only a normal termination, they will be correctly saved in the replacement destination sector. From the next time on, when accessing the sector deemed to be the defective sector, the replacement flag, head, and sector shown in FIG. 2 will be ON in the replacement processing, so the replacement destination shilling, head, and sector will be accessed.

[Effects] As described above, according to the present invention, since the determination of defective stored information is performed even at the time of normal termination, destruction of stored information can be prevented.

[BRIEF DESCRIPTION OF THE DRAWINGS] FIGS. 1A and 1B are configuration diagrams of sectors and ID sections on a conventional storage medium. FIG. 2 is a configuration diagram of an ID section on a recording medium to which an alternative method according to the present invention is applied. FIG. 3 is a flowchart showing a conventional sector access method, FIG. 4 is a flowchart showing a storage information replacement method according to the present invention, and FIG. 5 is a block diagram of a magnetic disk device. Here, 1...Control unit, 2...Head, 3...Magnetic disk, ra...Si/Rie number storage area. Patent Applicant: Canon Co., Ltd. - Figure 2 Figure 5 Procedural Amendment (jika) April 5, 1980 To the Commissioner of the Japan Patent Office 1, Case Indication Patent Application No. 1982-236050 2 , Alternative Method for Invention Name Storage Information 3, Person making the amendment Patent applicant: 3-30-2 Shimomaruko, Ota-ku, Tokyo (100) Canon Co., Ltd. 4, Agent: 105-5, Nikkan of the order for amendment 1972 March 27, 2015 (shipped) 6. Target of amendment (Figure 1 old) Rin ``7 dry-faced birds〒bar

Claims (1)

[Claims] A part of the storage information is provided with an area for storing the number of retry executions at the time of access, and when the number of retry executions in a certain access exceeds a certain judgment level, and the number of retry executions in the storage area exceeds the judgment level. A replacement method for stored information, characterized in that the stored information is determined to be defective and replaced.