JPH02210603A - Disk medium inspecting system - Google Patents

Abstract

PURPOSE:To simplify the constitution of a testing machine by including erase mode set information in a test command, and controlling a mode switching circuit by a signal based on the information. CONSTITUTION:The erase mode set information is included in the test command 16 from the testing machine 10 via an interface 12. An erase switching signal 20 is outputted from the control part 30 of a disk device 1 based on the information, and a switching circuit 18 is switched, and the erasure of a disk is performed by outputting selectively the erase information from the testing machine 10. And a reproducing signal from the disk is supplied to the testing machine, then, the normal/defective condition of the disk is decided. Therefore, no circuit to externally supply the switching signal to the switching terminal of the circuit 18 is required, which simplifies the constitution of the testing machine.

Description

[Detailed Description of the Invention] [Summary] Regarding a disk medium inspection method in which a disk device is connected to a testing machine to inspect the disk medium for defects, the present invention aims to simplify the configuration of the testing machine and provides an interface from the testing machine to the disk device. The command includes erase mode switching information, and based on this erase mode switching information, the switching circuit is configured to switch from normal mode to erase mode and perform track erase.

[Industrial Application Field] The present invention relates to a disk medium inspection method that connects a disk device to a testing machine to inspect disk media for defects.

In recent years, there has been a trend toward higher densities in magnetic disk drives and the like, and higher density disk media used in disk drives are also required.

As the density of disk media has increased, the number of man-hours required for each test to test disk media has increased significantly, and the hardware of testing machines has also become more complex. It is desirable to simplify the configuration of the test machine by implementing various test processes using software.

[Prior Art] FIG. 6 is a block diagram showing a conventional example of a disk medium inspection method.

In FIG. 6, 10 is a testing machine, and the testing machine 10 is provided with an interface control section 24, a write data control section 26, and an analog signal measurement section 28. A disk device 14 is connected to the tester 10, and the disk device 14 is provided with a control section 30, a switching circuit 32, a write signal modulation circuit 34, and a read signal demodulation circuit 36. A control terminal 38 is taken out from the switching circuit 32, and the switching circuit 32 can be switched by hardware by setting the control terminal 38 to H level or L level at TTL level, for example, by an external circuit (not shown).

In such a disk medium defect inspection method in which the disk device 14 is connected to the testing device 10, a command is issued from the testing device 10 to erase a predetermined track of the disk medium loaded in the disk device 14, and the erased data is erased. The reproduced signal of the recorded track is sent to the test 110, and medium defects are determined from the reproduced signal level.

That is, during defect inspection, the interface control section 24 of the testing machine 10 issues a command via the interface 12 in the same way as during normal write access by a host device, and the control section 30 of the disk device 14 puts it into a standby state. Subsequently, a switching control signal is applied to the control terminal 38 of the switching circuit 32 by an external circuit (not shown), and the erase write data and erase write gate from the write data control section 26 are selected and output to the write signal modulation circuit 34. Erases one track or all tracks of a disk medium.

When track erasing of the disk medium is completed, a reproduction signal consisting of the analog data and index of the erased track is sent from the read signal demodulation circuit 36 to the analog signal measuring section 28 of the tester 10, and is reproduced by the analog signal measuring section 28. The presence or absence of a medium defect is determined from the signal level.

[Problems to be Solved by the Invention] However, in such conventional disk medium inspection methods, during testing, an external circuit that switches to the erase side is tested using a switching terminal of a switching circuit provided in the disk device. Since it had to be installed on the machine side, there was a problem that the configuration of the test machine became more complicated.

The present invention has been made in view of such conventional problems, and an object of the present invention is to provide a disk medium inspection method in which the configuration of a tester is simplified as much as possible.

[Means for Solving the Problems] First, in the present invention, a test command 16 is issued from the tester 10 to the disk device 14 via the interface 12, and based on the test command 16, the disk device 14 executes the command from the test device. The present invention is directed to a disk medium inspection method in which a track of a disk medium is erased using erase information, a reproduced signal of the erased track is sent to a tester 10, and a medium defect is determined from the level of the reproduced signal.

Regarding such a disk medium inspection method, the present invention includes an erase mode in which erase information from the tester 10 is selectively output to the disk device, and write information generated internally when accessed by a host device is selectively output. A switching circuit 18 for switching between normal mode and normal mode is provided, erase mode setting information is included in the test command 16 issued via the interface 12, and the switching circuit 18 is switched to the erase mode by an erase switching signal 20 based on the erase information setting information. Configure.

Furthermore, the present invention provides a disk device itself that is equipped with such an inspection function.

[Function] In the disk medium inspection method according to the present invention having such a configuration, switching of the switching circuit provided in the disk device to the erase mode during testing is performed by an interface command from the tester to the disk device. This can be done using the included erase mode setting information, and the mechanism of the tester can be simplified to the extent that an external circuit for controlling the switching circuit in hardware is not required.

Of course, switching to erase mode is not only useful during testing.
This can be done arbitrarily by command from the host side.

Embodiment FIG. 2 is a block diagram showing an embodiment of the present invention.

In FIG. 2, reference numeral 10 denotes a testing machine, which includes an interface control section 24, a write data control section 26, and an analog signal measurement section 28. The interface control unit 24 issues a test command 16 to the magnetic disk device 14 via the interface 12 during a test, and in the present invention, in the test command 16, a command is provided on the magnetic disk device 14 side. It includes erase mode setting information for setting the switching circuit 18 to the erase mode. Note that as the erase mode setting signal included in the test command 16, in addition to using dedicated setting information, appropriate control information used for normal access control that is not used during testing may be used.

The write data control unit 26 performs track erase when inspecting a disk medium for defects.
Output. Here erase track write data C
is, for example, data that is all zero. Further, the analog signal measurement section 28 receives a reproduction signal from the erased track after track erasure of the disk medium loaded in the magnetic disk device 14 is completed, and determines whether there is a defect in the medium based on the signal level of the reproduction signal.

The disk device 14 is connected to the test 110 via the interface 12 and signal lines 58 and 60.

The disk device 14 is provided with an interface control section 30-1 and a disk control section 30-2 as control sections.

The interface control unit 30-1 includes an interface controller 40. It is equipped with an MPU 42 and a hard disk controller 44, and receives commands from the interface controller 40 via the interface 12.
The PU 42 decodes the data, and the hard disk controller 44 internally generates a write clock f, write data Q, and a write gate a. On the other hand, the disk controller 30-2 includes a drive controller 46 and an MPU 4.
Based on the command analysis information received via the hard disk controller 44, the MPU 48 performs a head seek using a servo circuit (not shown) via the drive controller 46, and in the present invention, the drive controller 46 When receiving a signal for decoding the erase mode setting information issued by the tester 10 via the tester 10, an erase mode switching signal 20 is generated.

Erase track/write clock b1 erase track/write data C1 from the write data control unit 26 provided in the testing machine 10 and the interface control unit 30
A write clock f, write data Q, and write gate a generated internally by the hard disk controller 44 provided in the hard disk controller 44 provided in the hard disk controller 44 provided in the hard disk drive 1 are input to the switching circuit 18. Further, the switching circuit 18 is supplied with a VFO clock d obtained from a VFO (not shown).

When the erase mode switching signal 20 from the drive controller 46 is at H level, the switching circuit 18 changes to the normal mode in which <NRZ write data e is generated based on the write clock f and write data Q internally generated from the hard disk controller 44. On the other hand, when the erase mode switching signal 20 is switched to the L level based on the erase mode setting signal from the tester 10 side, the switching circuit 18 receives the erase track/write clock b from the write data control section 26. Based on the erase track write data C, the mode is switched to an erase mode in which <NRZ write data e is generated. Note that in both the normal mode and the erase mode, a write gate a generated internally by the hard disk controller 44 and a VFO clock d generated by a VFO (not shown) are commonly applied.

The NRZ write data e from the switching circuit 18 is given to the write signal modulation circuit 34, subjected to predetermined signal modulation, and then written to a disk medium (not shown) by the head 52 via the head interface 50.

Further, a read signal demodulation circuit 36-1 that demodulates the reproduced signal from the head 52 is connected to the head interface 50, and the reproduced analog data from the read signal demodulation circuit 36-1 is transmitted to the analog signal measuring section 110 provided in test 1. 28
given to. Furthermore, a servo demodulation circuit 36-2 is provided, and a servo head 54 is provided for the servo demodulation circuit 36-2.
is connected via the servo interface 56, and outputs the reproduction signal from the servo head 54 to the servo demodulation circuit 36-2.
The index signal demodulated is output to the analog signal measuring section 28 of the tester 10.

Figure 3 shows the switching circuit 1 provided in the disk device 14 of Figure 2.
FIG. 2 is an example configuration diagram showing a specific example of B.

In FIG. 3, the switching circuit 18 is an inverter 62, 64
, AND gate 66.68, 72.74, OR gate 7
0.76 and D-FF78.80. This switching circuit 18 is supplied with a write gate signal a, an externally generated erase track write clock b, an erase track write data C1, and an internally generated write clock f and write data Q. NRZ write data e is output from the D-FF 80 at the final stage.

FIG. 4 is a timing chart showing the operation of the switching circuit 18 shown in FIG.
Test command 1 including erase mode setting information via
6 is issued.

That is, at time t1, the erase mode switching signal 20 is generated based on the erase mode setting information from the test 1110, and falls from the H level to the L level.

Therefore, the output of the inverter 62 in FIG. 3 becomes H level, and the AND gates 66 and 72 become in the allowable state, while the output of the inverter 64 becomes L level, so that the AND gates 66 and 72 are in the allowable state.
Gates 68,74 are placed in an inhibited state. That is, AND
By setting the gates 66 and 72 to the allowable state, the input of erase track write clock b and erase track write data C from the write data control section 26 of the testing machine 10 is enabled, while the internal input of the hard disk controller 44 is enabled. Write clock f and write data q generated in
input is invalidated.

Subsequently, at time t2, the write gate a from the hard disk controller 44 rises to H level, and the D-FF
78. Release the reset state of 80.

Subsequently, from time t3, AND gate 66 and OR gate 7
During the test, the erase track write clock b generated on the 10 side is supplied to the D-FF 78 via 0, and at the subsequent time t4, the erase track write clock b generated on the test machine 10 side is supplied via the AND gate 72 and the OR gate 76. Write data C is applied to the D terminal of D-FF7B. Therefore,
The output Q of the D-FF 78 rises to H level, and the erase track write data C is output to the D-FF 80 at the next stage. The D-FF 80 is driven by the VFO clock d and converts the erase track write data C received from the tester 10 at time t5 into the NRZ write data.
The data is output to the write signal modulation circuit 34 as data e, and the head 52 performs track erasing of the disk medium via the head interface 50.

Similarly, NRZ write data e corresponding to the erase track write data C obtained while the write gate a is maintained at the H level is sequentially generated, and one or more tracks are erased.

Next, the disk medium defect inspection operation in the embodiment shown in FIG. 2 will be explained with reference to the flowchart shown in FIG.

First, as shown in step S1 in FIG. 5, the tester 10 issues an erase track command to the interface 12 of the interface control section 24. The erase track command issued to the interface 12 is received by the interface control section 30-1 of the disk device 14, and as shown in step S2, the interface control section 30-1 sends the erase track command to the disk control section 30-2.
issue an internal request, i.e., an internal REQ, to
In the next step S3, command data for generating the erase mode switching signal 20, that is, internal command data is generated. Next, the disk control section 30-2
The internal acknowledgment shown in step S4 to the interface control unit 30-1, that is, the internal ACK
After performing this, in step S5 the drive controller 4
Erase track mode is set to 6, and switching circuit 1
8, an erase mode switching signal 20 is output. Subsequently, in step S6, the interface control unit 30
The hard disk controller 44 on the −1 side gives an on signal for the write gate a to the switching circuit 18, and the fourth
As shown in the timing chart in the figure, the switching circuit 18 generates NRZ write data e based on the erase track write clock b and erase track write data C from the write data control unit 26 of the tester 10. Erasing is performed at a track position that has been subjected to seek control by the disk control unit 30-2.

In the embodiment shown in FIG. 2, the erase track/write clock b and the erase track/write signal are sent to the switching circuit 18 on the disk device 14 side from the write data control unit 26 provided in the tester 10 via the signal line 58. Although the track erase is performed by giving data C, in another embodiment, the hard disk controller 44 erases based on a test command from the interface control unit 24 without receiving erase information from the write data control unit 26. The track write clock b and the erase track write data C may be generated and applied to the switching circuit 18.

Furthermore, although the above embodiments are used only during testing, if the disk device has such an inspection function, it may be possible to switch to the erase mode by receiving a command from the host at times other than testing.

[Effects of the Invention] As described above, according to the present invention, the switching circuit on the disk drive side can be switched to the erase mode by software using an interface command from the test device, so that an external switch for switching to the erase mode can be used. There is no need to provide a circuit on the test line side, and the configuration of a tester for erasing the medium when inspecting the medium for defects can be greatly simplified. The same holds true when the host issues a command to switch to erase mode.

[Brief explanation of the drawing]

Fig. 1 is an explanatory diagram of the principle of the present invention; Fig. 2 is a block diagram of an embodiment of the present invention; Fig. 3 is a block diagram of an embodiment of the switching circuit of the present invention; Fig. 4 is a timing chart of the switching circuit of the present invention. FIG. 5 is an operational flow diagram of the present invention; FIG. 6 is a configuration diagram of a conventional system. In the figure, 10: Test machine 12: Interface 14: Disk device 16: Test command 18: Switching circuit 20: Erase switching signal (erase mode switching signal) 24: Interface control unit 26: Write data control unit 28: Analog signal measurement Section 30: Control section 30-1: Interface control section 30-2:
Disk control unit 34: Write signal modulation circuit 36. 36-1: Read signal demodulation circuit 36-2: Servo demodulation circuit 40: Interface controller 42. 48: MPU 44: Hard disk controller 46: Drive controller 50: Head interface 52: Head 54 : Servo head 56: Servo interface 58.60: Signal line 62.64: Inverter 6.68, 72, 74: A N D gate 70.7
6: OR gate 78.80: D-FF

Claims (2)

[Claims] (1) A test command (16) is issued from the tester (10) to the disk device (14) via the interface (12), and based on the test command (16), the disk device (
In step 14), the erase information from the tester (10) is used to erase the tracks on the disk medium, and the reproduced signal of the erased track is sent to the tester (10) to determine the quality of the medium based on the level of the reproduced signal. In the disk medium inspection method for determining the erase mode, an erase mode in which erase information from the tester (10) is selectively outputted to the disk device (14), and erase information generated internally based on access from a host device are provided. A switching circuit (18) is provided for switching between a normal mode in which write information is selectively output, and erase mode setting information is included in the test command (12) issued via the interface (12), and erase mode is performed based on the erase mode setting information. Switching signal (20)
A disk medium inspection method characterized in that the switching circuit (18) is switched to an erase mode. (2) a switching circuit (18) capable of switching between an erase mode for selectively outputting erase information for erasing tracks on a disk medium and a normal mode for selectively outputting write information for writing on tracks on a disk medium; from a received command; A disk device comprising: a control section (30) that outputs a switching signal (20) to the switching circuit (18) to switch to the erase mode when erasing mode switching information is decoded.