JPH0721698A - Method for certifying flexible disk - Google Patents

Abstract

PURPOSE:To improve manufacture efficiency by using format data or application data as test signals for a flexible disk to be certified. CONSTITUTION:First, inspection reference for comparing the test signal is set. Then, the format data or the application data are written on the disk to be certified as the test signals. Then, the written test signals are read at every bit and a drop-out test is performed based on the inspection reference. Further, the written test signal are read at every bit and a drop-in test is performed based on the inspection criterion. Then, when a missing pulse or an extra pulse is detected by the drop-out test and the drop-in test, an error detection code is written at the defect map write position of the track as bit information.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a flexible disk certifying method, and more specifically,
In particular, the present invention relates to a certifying method for a flexible disk that can improve the manufacturing efficiency by simultaneously performing the certifying and formatting when manufacturing the initialized flexible disk.

[0002]

2. Description of the Related Art In general, a flexible disk cartridge (flexible disk) is manufactured by providing a magnetic layer on the surface of a flexible support and then mounting a drive hub and housing it in a case in an assembly process. To be done.
Then, it is supplied to a certifying step for testing electrical and magnetic characteristics, and it is confirmed whether or not a bit is dropped.

The above certifying method is usually performed by the following steps. First, after writing the test signal to the disk, the written test signal is read out to perform the dropout test. That is, the test signal at the time of writing and the test signal at the time of reading are compared to detect a so-called missing pulse (signal error) in which the individual pulse output amplitude at the time of reading does not meet a predetermined reference.

Next, after the test signal written on the disk is erased by applying a predetermined DC magnetic field, the remaining test signal is read again to perform a drop-in test. That is,
By comparing the test signal at the time of writing with the remaining test signal at the time of reading, a so-called extra pulse (signal error) whose output amplitude at the time of reading exceeds a predetermined reference is detected.

When a signal error is detected by each of the above tests, it is written on the disk as bit information. Note that the above certifying method is an analog certifying method, but a digital certifying method in which each test is performed by setting the window width of the magnetic flux reversal interval is also adopted.

[0006]

By the way, recently, it is required to manufacture an initialized recording medium, and it is necessary to write format data and the like to a disc. However, from the recognition that it is necessary to use a constant frequency pattern signal as a test signal in the certify method, in the manufacture of an initialized recording medium, certify and subsequent writing of format data etc. are performed separately. Therefore, there is a problem that the manufacturing efficiency is reduced, and a method for improving the problem is desired.

The present invention has been made in view of such circumstances, and an object thereof is to provide a flexible flexible disk capable of improving the manufacturing efficiency by performing the formatting at the same time as the certification when manufacturing the initialized flexible disk. It is to provide a method of certifying a disc.

[0008]

That is, the gist of the present invention resides in a certifying method for a flexible disk characterized by using format data or application data as a test signal.

[0009]

The present invention will be described in detail below with reference to the drawings. FIG. 1 is a flow chart showing a certifying method for a flexible disk according to the present invention. FIG. 2 is an explanatory diagram showing an analog certifying method, which is one aspect of the test signal inspection reference in the flexible disk certifying method of the present invention. FIG. 3 is an explanatory diagram showing another aspect of the inspection standard of the test signal in the certifying method of the flexible disk of the present invention, which is a digital certifying method.

The flexible disk certifying method of the present invention can be applied to flexible disks of various standards such as FM recording method and MFM recording method, for example, diameters of 200 mm, 130 mm and 90 mm.
It can be easily applied to the certifying process incorporated in the conventional manufacturing process. Then, similar to the conventional certifying method, the analog certifying and the digital certifying can be performed by the method of setting the inspection standard when performing the drop-out test and the drop-in test.

First, an analog certifying method will be described as one embodiment of the present invention. In the certifying method of the present invention, initially, as shown in FIG. 1, an inspection standard for comparing test signals is set (step (S ₁ )). In the analog certification, such inspection standard is set by the slice level (output amplitude). That is, as shown in FIG. 2, regarding the pulse output amplitudes of the individual read data (1) and (0),
Predetermined reference peak output voltages (P _h ) and (P _l ) are set.

Of these reference peak output voltages, the reference peak output voltage (P _h ) indicates the minimum height of the peak corresponding to the read data (1), and the reference peak output voltage (P _l ) is The maximum height of the peak corresponding to the read data (0) is shown. Such a reference value is, for example, a value of an amplitude measurement method that is generally adopted according to the recording density of the medium. Then, the reference peak output voltage (P _h ) is used for the dropout test, and the reference peak output voltage (P _l ) is used for the drop-in test.

Next, in the present invention, the certify
Format disc as a test signal
Data or application data (step
(S ₂)). Format data or application
The data is a pre-initialized flexible disk.
Various publicly known software used for commercialization
You can use In addition, such operations are commonly used
Disk drive, and usually one
Do about Ku.

Next, the written test signal is read out for each bit (step (S ₃ )), and a dropout test is carried out based on the above inspection standard. In that case, among the output pulses, one that exceeds the reference peak output voltage (P _h ) is recognized as data (1). Then, the data (1) and (0) in the test signal at the time of writing and the data (1) and (0) in the test signal at the time of reading are compared for each bit (step (S ₄ ). A bit for which the data (1) at the time of writing is detected as the data (0) at the time of reading is determined to have a missing pulse (signal error).

Further, the written test signal is read out for each bit (step (S ₅ )), and a drop-in test is carried out based on the above inspection standard. In that case, among the output pulses, those that are lower than the reference peak output voltage are recognized as data (0). Then, the data (1) and (0) in the test signal at the time of writing and the data (1) and (0) in the test signal at the time of reading are compared for each bit (step (S ₆ )). As a result, it is determined that there is an extra pulse (signal error) for the bit in which the data (0) at the time of writing is detected as the data (1) at the time of reading.

Next, when a missing pulse or an extra pulse is detected by the above-mentioned drop-out test and drop-in test, an error detection code is written as bit information at the defect map writing position of the track (step (S ₇ )). ). Then, after certifying one track, the other tracks are sequentially processed from step (S ₂ ) to step (S ₇ ).
Repeat the operation up to.

That is, in the present invention, the flexible disk can be initialized at the same time as certifying by performing the above-mentioned operation for each track. Further, in the flexible disk such certification has been completed, supplies the defective bit is the product of step a the following predetermined criteria (step (S _8)).

Next, a digital certifying method will be described as another embodiment of the present invention. In the digital certifying method, the inspection standard is set by the window width of the magnetic flux reversal interval in step (S ₁ ) in FIG. That is, as shown in FIG. 3, predetermined reference periods (T _s ) and (T _l ) are set for the detection widths of the magnetic flux reversal intervals of the individual read data (1) and (0).

Of these reference periods, the reference period (T _s )
Indicates the shortest period including magnetic flux reversal corresponding to the read data (1), and the reference period (T _l ) indicates the longest period corresponding to read data (0) without magnetic flux reversal.
Such a reference value is, for example, a value of a commonly used method of measuring the magnetic flux reversal interval. Then, the shortest period (T _s ) including the magnetic flux reversal is used for the dropout test, and the longest period without magnetic flux reversal (T _l ) is used for the drop-in test.

Then, in the step (S ₄ ) in FIG. 1, among the output pulses, the one in which the magnetic flux is inverted in the shortest period (T _s ) is recognized as the data (1), and the writing test is performed. Data (1) and (0) in the signal and data (1) and (0) in the test signal at the time of reading are compared for each bit. As a result, the data when writing (1)
A bit detected as data (0) during reading is determined to have a missing pulse (signal error).

Further, in the step (S ₆ ), among the outputted pulses, the one in which the magnetic flux is not reversed in the longest period (T _l ) is recognized as the data (0), and the data (the data in the test signal at the time of writing) is recognized. 1) and (0) are compared with the data (1) and (0) in the test signal at the time of reading for each bit. As a result, it is determined that there is an extra pulse (signal error) for the bit in which the data (0) at the time of writing is detected as the data (1) at the time of reading. The other steps are the same as those in the above embodiment. That is, also in the other aspect of the present invention, similarly to the above aspect, it is possible to initialize the flexible disk simultaneously with the certify.

In each of the above aspects, when performing a dropout test and a dropin test,
The same read circuit is used in step (S ₃ ) and step (S ₅ ) in FIG. 1, and a special comparison circuit corresponding to each test is used in step (S ₄ ) and step (S ₆ ). ing. Therefore, step (S
By simultaneously inputting the test signal read in ₃ ) to each comparison circuit, the dropout test in step (S ₄ ) and the drop in step (S ₆ ) can be performed without executing the read again in step (S ₅ ). The IN test can be performed in parallel, and the certification and the initialization can be performed more efficiently.

[0023]

According to the present invention, since the format data or the application data is written as a test signal from the beginning to the flexible disk to be certified, the initialization of the flexible disk is completed when the certification is completed. Therefore, it is not necessary to separately provide a formatting process when manufacturing the initialized flexible disk, and the manufacturing process can be simplified. Further, according to the present invention, it is possible to shorten the time required to carry from the certify process to the format process and the time required for the format in the conventional manufacturing process, so that the manufacturing efficiency can be improved and the manufacturing cost can be reduced. You can do it.

[Brief description of drawings]

FIG. 1 is a flowchart showing a certifying method for a flexible disk according to the present invention.

FIG. 2 is an explanatory view showing one mode of a test signal detection reference in the flexible disk certifying method of the present invention.

FIG. 3 is an explanatory diagram showing another aspect of a test signal detection reference in the flexible disk certifying method of the present invention.

[Explanation of symbols]

P _h, P _l: reference peak output voltage T _s, T _l: reference period

Claims (1)

[Claims] 1. A certifying method for a flexible disk, wherein format data or application data is used as a test signal.