KR100265123B1 - Method for improving hard disc drive through head mapping - Google Patents

Abstract

PURPOSE: A reliability improving method of an HDD(Hard Disk Drive) is provided to enhance reliability of a drive by recording system information on a disk having high head characteristics. CONSTITUTION: Head assembling performance of each drive is tested to select a head having the highest performance. The selected head number(X) is recorded on a maintenance cylinder of a disk or on a flash memory of a microcontroller. The microcontroller reads the X out of the maintenance cylinder or a flash memory in a booting process. Then, the microcontroller sets the X as logical head number zero and numbers the logical head by adding the X to the logical head number zero. If the selected head number is 2, an added value of the X to the logical head number becomes a logical head number. Therefore, reliability of a drive is improved through the head mapping without greatly changing programs for recording system information.

Description

How to Improve Hard Disk Drive Reliability by Head Mapping

The present invention relates to a hard disk drive, and more particularly, to a method of improving reliability of a hard disk drive through head mapping.

In addition to user data, data information about parameters necessary for the drive itself is recorded on a disk of a hard disk drive that is used as an auxiliary storage device of a computer system. Define) is read and used at drive boot time. If a part of the data recorded in the user data area is damaged when the hard disk drive is used, only a part of the recorded data is lost. However, if the system information is damaged, the drive cannot be operated. Therefore, preservation and management of system information requires special attention to secure drive reliability.

A typical hard disk drive manufacturer records the system information on the disk surface corresponding to the head 0 normally. However, the performance of the head varies depending on the mechanical assembly state, the inherent characteristics of the head or the coupling relationship with the disk, so that head 0 is not the most reliable. Therefore, in the conventional hard disk drive, there is a problem that the drive reliability can be reduced by uniformly recording system information on the disk surface corresponding to the head 0 without considering the head characteristics.

Accordingly, an object of the present invention is to provide a method for improving system reliability by recording system information on a disk surface having excellent head characteristics.

In order to achieve the above object, the present invention relates to a method of improving reliability of a hard disk drive having a flash memory and a plurality of heads, the method of testing the characteristics of each head for the operation of the drive on a head disk surface having the highest performance. The data information is recorded and used during booting.

1 is a block diagram of a typical hard disk drive.

2 is a flowchart of a headmapping process according to an embodiment of the present invention.

3 is an exemplary head correspondence diagram for explaining a correspondence relationship between a logical head number and a physical head number through head mapping according to an embodiment of the present invention.

Hereinafter, exemplary operations of the present invention will be described in detail with reference to the accompanying drawings.

1 is a general block diagram of a hard disk drive, showing an example of a hard disk drive having two disks 2 and four heads 4 corresponding thereto. Referring to FIG. 1, the disks 2 are typically mounted in one spindle motor 26 in a stack form, each disk surface corresponding to one head 4. The head 4 is located on the surface of the disk 2 and is mounted on a vertically extending arm 6 of an arm assembly of a rotary voice motor (VCM) 20. The preamplifier 8 preamplifies the signal picked up by one of the heads 4 during data read and applies the analog read signal to the read / write channel circuit 10, At the time of data writing, encoded write data applied from the read / write channel circuit 10 is driven to drive the corresponding one of the heads 4 onto the disc 2. At this time, the preamplifier 8 selects one of the heads 4 under the control of the disk data controller (DDC) 28. The read / write channel circuit 10 detects and decodes a data pulse from a read signal applied from the preamplifier 8 to generate read data RDATA, and decodes the write data WDATA applied from the DDC 28 to decode the preamplifier 8. ) Is applied. The read / write channel circuit 10 also demodulates the head position information which is a part of the servo information recorded on the disk to generate a position error signal (PES). The PES generated from the read / write channel circuit 10 is applied to an analog-to-digital converter 12, and the A / D converter 12 sets the PES to a digital step value corresponding to its level. To the microcontroller 14. The DDC 28 is controlled by the microcontroller 14 and writes data received from the host computer onto the disc 2 via the read / write channel circuit 10 and the preamplifier 8 or onto the disc 2. The data is read from the host computer and sent to the host computer. The DDC 28 also interfaces the communication between the host computer and the microcontroller 14. The microcontroller 14 controls the DDC 28 in response to read or write commands received from the host computer and controls track search and tracking. At this time, the microcontroller 14 controls the track tracking as described above using the PES value applied from the A / D converter 12. The microcontroller 14 includes a ROM having a drive control program of a hard disk and a flash memory for recording system information according to an embodiment of the present invention. The digital-to-analog converter 16 converts a control value for position control of the heads 4 generated from the microcontroller 14 into an analog signal and outputs the analog signal. The VCM driver 18 generates a driving current I (t) for driving the actuator by the signal applied from the D / A converter 16 and applies it to the VCM 20. The VCM 20 moves the head 4 horizontally on the disk 2 in response to the direction and level of the drive current input from the VCM driver 18. The motor controller 22 controls the spindle motor driver 24 according to the control value generated from the microcontroller 14. The spindle motor driver 24 rotates the disks 2 by driving the spindle motor 26 under the control of the motor controller 22.

2 is a diagram illustrating a head mapping process flow chart according to an embodiment of the present invention, in which the system information is recorded at the time of booting after recording the system information on the head / disk surface having the best performance by measuring the head / disk performance during the production process. The flowchart shows the process from reading and using.

3 is an exemplary head corresponding diagram for explaining a correspondence relationship between a logical head number and a physical head number through head mapping according to an embodiment of the present invention. Hereinafter, a head mapping process according to an embodiment of the present invention will be described with reference to FIGS. 1 and 3.

First, the hard disk drive manufacturer selects the best performing head in 50 steps by testing the performance of the heads in each drive. In this case, an error rate measuring method or a performance evaluation function supported by the read / write channel circuit may be used as the test method. Thereafter, in step 52, the head number selected in step 50 is recorded on the maintenance area on the disc 2 or on the flash memory provided in the microcontroller 14. In the following description, the selected head number is defined as X. Thereafter, the microcontroller 14 of each drive that has undergone a production process reads the head number X recorded in the maintenance area or the flash memory in step 54 at boot time, and then proceeds to step 56. In step 56, the microcontroller 14 sets the read head number to a logical head number zero, adds the read head number X to a logical head number zero, and then reads the read head number zero. The added head number (X) is added to number the logical heads. That is, if the head number selected in the head test as shown in FIG. 3 is "2", the value obtained by adding the selected head number to the logical head number becomes the logical head number. Therefore, the reliability of the drive can be improved by using the above-described head mapping method without large changes in the conventional program for recording system information on the head 0.

As described above, the present invention has the advantage of improving the reliability of the drive by testing the head characteristics provided in each drive and recording system information on the display surface corresponding to the head having the highest performance.

Claims (4)

A method of improving the reliability of a hard disk drive having a flash memory and a plurality of heads, the method comprising: testing the performance of the heads of the hard disk drive, identifying the head having the best performance as a result of the test; And recording the data information on the operation of the drive on the disk surface of the identified head so that it can be used during booting. The method of claim 1, wherein the head information having the highest performance after completion of the test is written to the flash memory and read at the time of booting of the drive to be used as a logical head number zero. 3. The method of claim 2, wherein the head information is tested during the production process of the drive and recorded on the flash memory. 3. The method of claim 2, wherein the head information is recorded in a maintenance area on the disk.