JPH06302089A - Magnetic recording and reproducing device - Google Patents

Abstract

PURPOSE:To provide an information recording and reproducing device which can connect to plural host systems in which allowable parameters are different from each other. CONSTITUTION:An information recording and reproducing device is provided with a starting parameter table recorded in a ROM 34, and a switching means 13 selecting externally a desired starting parameter out of this parameter, being connected to a host system, performs writing and reading a signal. Since the starting parameter selected by the switching means 13 is sent out to the host system base on a request of the host system, a parameter adaptable to the host system can be sent out, and the device can be connected to plural host systems in which allowable parameters are different.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an information recording / reproducing apparatus, and more particularly to an information recording / reproducing apparatus for recording / reproducing information on a magnetic disk rotatably held inside the apparatus by using a magnetic head.

[0002]

2. Description of the Related Art A conventional information recording / reproducing apparatus will be described with reference to FIG. As a conventional information recording / reproducing apparatus, for example, a magnetic disk in which a magnetic recording layer is formed on a hard disk surface is rotationally driven, and information is written / read by a head flying over the magnetic disk. What is done is known. In such a hard disk drive, a magnetic disk 8 attached to the rotation drive means 36 and an arm 4 for attaching the magnetic head 2 to the tip and a coil 5 to the other end to move the magnetic head 2 to a desired read / write position. And the coil 5
A drive means 17 for the arm 4 including a pair of yokes 6 and a magnet 7 provided so as to face the coil 5, a drive circuit for controlling them, and a control circuit for controlling reading and writing of signals from the magnetic disk 8 are mounted. And a control board 10.

Next, the format of a magnetic disk used in such a conventional information recording / reproducing apparatus will be described. A plurality of tracks are formed on the magnetic disk for recording information in the radial direction, and each track has a plurality of circumferentially divided recording areas called sectors. Each sector, which is a recording area, is divided into a servo area in which servo information such as a track number is written, a burst area for subsequent tracking, and a data area in which data from the host system is recorded. , A plurality of these are continuously provided on the track.

Next, writing of data from the host system to the information recording / reproducing apparatus thus formatted will be described. The information recording / reproducing apparatus, which has received the write request from the host system, moves the head to a desired track based on the servo information on the magnetic disk, and the burst signals A and B are written in a zigzag pattern in the burst area. Fine tracking to the center position of the desired track in the width direction is performed by comparing the output values of. Then, the information transferred from the host system is converted into a signal by the control circuit and sent to the magnetic head to write to the magnetic disk.

Such an information recording / reproducing apparatus is connected to a host system such as a computer which is a host apparatus, and records / records information such as data in response to a request from the host system.
Although the reproduction is performed, the following methods have been used for starting the information recording / reproducing apparatus from the host system.

When the power of the host system is turned on, the host system sends an ID to the connected information recording / reproducing apparatus.
Send the ENTIFY command. The information recording / reproducing apparatus which has received the IDENTIFY command reads out parameters such as the number of physical cylinders, the number of heads, the number of sectors, etc., which are stored in advance in a storage means such as a ROM in the information recording / reproducing apparatus and sends them to the host system. Next, the host system checks whether the received parameters are suitable for the host system, and if they are, the received parameters, that is, the number of physical cylinders, the number of heads, and the number of sectors are set to the number of logical cylinders. , The information recording / reproducing apparatus operates as the number of logical heads and the number of logical sectors.

[0007]

In a host system to which such an information recording / reproducing apparatus is connected, the maximum capacity of the information recording / reproducing apparatus accessible by the host system is the allowable number of cylinders and the allowable number of heads in the BIOS. , The allowable number of sectors is specified, for example, P manufactured by IBM
In the C-AT type computer, 1024 cylinders, 16 heads and 64 sectors are the maximum allowable values. By the way, in recent years, the information recording / reproducing apparatus has become higher in recording density and thinner, and there is a demand for an information recording / reproducing apparatus having a higher track density and a smaller number of heads (a smaller number of magnetic disks). Along with this, an information recording / reproducing apparatus has been developed in which the number of cylinders exceeds the allowable number of cylinders, such as 2108 cylinders, 4 heads, and 49 sectors. However, in contrast to the type in which the IDENTIFY command is sent when the information recording / reproducing apparatus is activated from the host system, if the information recording / reproducing apparatus exceeding the allowable number of cylinders is connected as described above, it is not suitable for the host system at the time of activation. There was a case where an error occurred because the device was regarded as an information recording / reproducing device.

Further, in such an information recording / reproducing apparatus, when external vibration or shock is applied to the apparatus at the time of writing data from the host system, the position of the magnetic head deviates from a desired track and an off-track error occurs. There was something to do. In such a case, the information recording / reproducing apparatus temporarily interrupts the writing operation, performs error recovery processing to return the magnetic head to the regular writing position, and restarts the writing operation after the magnetic head returns to the regular writing position. . Here, the resumption of the writing operation will be further described. Writing at the time of resumption was started from the sector in which the off-track error was detected. However, it is considered that the actual off-track occurrence of the magnetic head occurs continuously from the sector several sectors before the sector judged as the off-track error. This is mainly due to the time required from the detection of the current position of the magnetic head to the determination of off-track. Obey,
In the conventional information recording / reproducing apparatus, even in a sector several sectors before the sector determined to be an off-track error, the output level becomes small at the time of reading data, which may lead to a read error.

The present invention has been made in view of the above circumstances, and a first object thereof is to provide an information recording / reproducing apparatus which can be connected to a plurality of host systems having different allowable parameters such as the number of cylinders. To provide.

A second object of the present invention is to provide an information recording / reproducing apparatus which realizes writing with high reliability even when an off-track error occurs.

[0011]

As a means for solving the above problems, the first object of the present invention is to select a starting parameter table and desired starting parameters from the parameter table from outside the apparatus. In the information recording / reproducing apparatus which is connected to the host control device and writes / reads signals, the start-up parameter selected by the switching unit is sent to the host device based on a request from the host control device. This is achieved by the first means adapted for delivery.

A second object of the present invention is to provide a head for writing / reading a signal to / from a recording medium having a plurality of divided recording areas formed on a plurality of recording tracks, and a recording medium. In an information recording / reproducing apparatus having means for rotationally driving, means for positioning the head on a recording track, and means for detecting a positional deviation of the head on a target recording track, if the positional deviation is detected at the time of writing information. This is achieved by the second means for rewriting information from the recording area on the downstream side of the rotation of the recording medium from the head position at the time of detecting the positional deviation.

[0013]

According to the above-mentioned first means, since the start-up parameter switching means selects the start-up parameter according to the host system from the outside of the apparatus, the start-up parameter suitable for the host system can be transmitted, and the permissible parameter can be transmitted. It is possible to connect to a plurality of host systems of different types.

According to the above-mentioned second means, even if an off-track error occurs during writing, information can be rewritten not only in the recording area where the positional deviation is detected but also in the recording area where the positional deviation may occur. Since it is performed, highly reliable writing can be performed.

[0015]

Embodiments of the present invention will now be described in detail with reference to the drawings, using a magnetic disk drive device as an example. FIG. 1 is a perspective view showing the whole of a magnetic disk drive which is an information recording / reproducing apparatus embodying the present invention, FIG. 2 is a block diagram of a control circuit of the magnetic disk drive according to the embodiment, and FIG. 5 is a diagram showing a format of a magnetic disk of a magnetic disk drive according to the embodiment, FIG. 4 is a circuit diagram of a start parameter switching means of the magnetic disk drive according to the embodiment, and FIG. 5 is a magnetic disk according to the embodiment. 6 is a flowchart relating to off-track error recovery at the time of writing of the drive device, and Table 1 is a start-up parameter table of the magnetic disk drive device according to the embodiment.

This type of magnetic disk drive includes a chassis 1, a magnetic disk 8 having a hard disk on which a magnetic layer is formed, and a magnetic disk 8 exposed on the upper surface of the chassis 1.
A spindle motor 36 as a rotation drive mechanism for rotatably supporting the disk, a substantially triangular support plate 3 on the tip of which a magnetic head 2 for writing / reading signals facing the magnetic disk is projected, and at one end An arm 4 to which a support plate 3 is attached and a flat coil 5 is adhesively fixed to the other end, a pair of yokes 6 and a magnet 7 facing the coil 5 and fixed to the chassis 1, and a control of a magnetic disk drive device. It is mainly composed of a control board 10 on which a circuit is mounted. The arm 4 is rotatably supported by the chassis 1 about a pivot shaft 9 as a center of rotation, and the VCM 17 including the coil 5, the yoke 6 and the magnet 7 is energized to move the magnetic head 2 in the radial direction of the magnetic disk 8. Drive to. R /
One end of the flexible circuit board 15 mounted with the W amplifier 14 and fixed to the upper surface of the chassis 1 is connected to the arm 4,
The other end is connected to the control board 10. The control board 10 has a connector 11 for transmitting and receiving a signal from a host system (not shown), a connector 12 to which power is supplied from the host system, and a jumper 18 to which a short pin plug 13 is attached. Then, except for the control board 10, the magnetic disk 8, the spindle motor 36,
The components such as the arm 4, the VCM 17, and the flexible circuit board 15 are hermetically housed between the chassis 1 and a lid (not shown), and the control board 10 is fixed to the lower surface of the chassis.

A magnetic disk drive unit 3 is mounted on the control board 10.
7, a hard disk control CPU 21 for controlling the interface between the host system 20 and the magnetic disk drive 37, format control, error correction, etc.
A mechanical control CPU 23 for mechanically controlling the magnetic disk drive device 37 is mounted, and these two CPUs are the core of control of the magnetic disk drive device 37. The mechanical control CPU 23 includes a hard disk control CPU 21, a servo timing generator 25, a track register 26, an A / D converter 27,
The spindle motor drivers 35 are connected to each other so that signals can be exchanged in both directions.

The hard disk control CPU 21 is connected to a buffer RAM 22, a data processing circuit 24, and a ROM 34 in which start-up parameters are written so that signals can be transmitted and received bidirectionally, and also via the connector 11. A host system 20, which is a host system, is connected so that signals can be exchanged bidirectionally.

A data processing circuit 24, a pulse detector 31, and a peak detector 33 are connected to the output terminal of the servo timing generator 25, and a spindle motor 36 is bidirectionally signaled to a spindle motor driver 35. It is connected so that it can be exchanged. A D / A converter 28 is connected to the output terminal of the mechanical control CPU 23, an analog correction circuit 32 is connected to the output terminal of the D / A converter 28, and a VCM driver 30 is connected to the output terminal of the analog circuit 32. The output terminal of the VCM driver 30 is connected to the VCM 17 via the flexible circuit board 15.
It is connected to the.

The magnetic head 2 and the R / W amplifier 14 are connected via the flexible circuit board 15 so that signals can be exchanged in both directions. The output terminal of the R / W amplifier 14 is a pulse detector. 31 connected to the pulse detector 3
The output terminal of 1 is the data processing circuit 24, the servo decoder 2
9, the peak detector 33 is connected, and the output terminal of the data processing circuit 24 is connected to the R / W amplifier 14. The output terminal of the servo decoder 29 is connected to the servo timing generator 25 and the track register 26. The output terminal of the peak detector 33 is an A / D
It is connected to the converter 27.

The magnetic surface of the magnetic disk 8 is formed with a plurality of recording tracks 40 in the radial direction. FIG. 3 is a schematic view in which the recording track is linearly opened. The recording track 40 is divided into a plurality of sectors 41 in the circumferential direction,
In these sectors 41, servo sectors 42 used for tracking toward the rotation direction A of the magnetic disk 8 in FIGS. 1 and 3 and data sectors 43 in which data is subsequently written are alternately formed. In the servo area 44 in which servo information such as a track number is written, and the center lines of the recording tracks 40 adjacent to each other are used as boundaries, the A bursts 45, B are formed in a staggered manner.
A burst 46 is provided. Further, in the data sector 43, an ID portion 47 in which position information such as a cylinder number, a head number, and a sector number is written, a data portion 48 in which information from the host system is recorded subsequently, and error correction information in succession thereto. An ECC section 49 in which is written is provided.

An air bearing surface (not shown) is formed on the surface of the magnetic head 2 that faces the magnetic disk 8, and the magnetic disk 8 is formed by the spindle motor 36.
The magnetic head 2 floats above the surface of the magnetic disk 8 while maintaining a minute gap by the airflow generated by the high speed rotation of the magnetic disk passing through the air bearing surface. Then, the magnetic disk drive device 37 exchanges data with the host system 20 in response to a request from the host system 20.

Next, means for switching the starting parameters of the magnetic disk drive device 37 will be described with reference to FIG. 4 and Table 1.

[0024]

[Table 1]

The hard disk control CPU 21 is connected to the ROM 34 which stores start-up parameters. The ROM 34 will be further described.
34, the number of cylinders, the number of heads, and the number of sectors are stored in advance as a table of startup parameters at the time of shipment or by the user.
Then, the jumper 1 arranged at one end of the control board 10
8 is a pair of connection pins 18a, 18b and 18 respectively.
It is composed of c and 18d. The short pin plug 13 includes a resin case 13 and a conductive connecting piece, and the connecting piece is housed and held in a hole formed in the case. And one connection pin 1 of the jumper 18
8a and 18c are connected to a power source through resistors, and the connection pins 18a and 18c are identification terminals 50,
It is connected to the hard disk control CPU 21 of the control board 10 by 51. The other connection pins 18b and 18d are grounded via resistors. The connection pins 18a-18b of the jumper 18 and the connection pins 18c-18d of the jumper 18 can be switched to be short-circuited or open by mounting the short-pin plug 13 at the time of shipment or by the user.

Next, the magnetic disk drive device 37 of the present invention.
The startup from the host system 20 will be described. When the power of the host system 20 is turned on, the host system 20 sends I to the connected magnetic disk drive 37.
Send the DENTIFY command. Where IDEN
The TIFY command is a command used in a computer that complies with the AT standard. IDENTIFY
Upon receiving the command, the hard disk control CPU 21 of the magnetic disk drive drives the identification terminal 50,
According to the output of 51, the corresponding starting parameter is read from the parameter table of the ROM 34 and transferred to the host system. For example, the shorting plug 13 is connected between the connecting pins 18a-18b and short-circuited, and 18c-18
If the shorting plug 13 is not connected between d and is in an open state, the output of the identification terminal 50 becomes low level and the output of the identification terminal 51 becomes high level, which are sent to the hard disk control CPU 21. As a result, the hard disk control CPU 21 causes the RCM3
The corresponding parameters, that is, the number of cylinders 615, the number of heads 8 and the number of sectors 17 are read from the parameter table of No. 4 and transferred to the host system.

Next, the host system 20 confirms whether or not the received parameters are suitable for the host system 20, and the transferred parameters are selected in advance from the parameter table so as to be compatible with the host system 20. Since it does exist, it will not cause an error due to being incompatible with the host system. Then, the magnetic disk drive operates with the parameters received by the host system 20 as the number of logical cylinders, the number of logical heads, and the number of logical sectors, respectively.

Here, in the embodiment, the number of cylinders, the number of heads,
Each of the number of sectors is stored in the parameter table, but one or two of the above parameters such as only the number of cylinders or only the number of cylinders and the number of heads are used in combination within the range compatible with the host system. You may do it. Further, the description has been made by using the combination of the two sets of short plugs and the connecting pins as the switching means, but the number of the switching means may be increased or decreased according to the number of parameters, or the switching may be performed by using other selection means such as a slide switch. You may

Next, the read operation of the magnetic disk drive device 37 according to the present invention will be described. The magnetic disk drive 37 activated by the host system 20
Rotate the spindle motor 36 to drive the magnetic disk 8
Rotate at high speed. An air bearing surface (not shown) is formed on the surface of the magnetic head 2 facing the magnetic disk 8, and the airflow generated by the high speed rotation of the magnetic disk 8 passes through the air bearing surface. The magnetic head 2 flies over the surface of the magnetic disk 8 while maintaining a minute gap.

When a seek command is issued from the host system 20, the seek command is input to the mechanical control CPU 23 via the hard disk control CPU 21, and the seek signal from the mechanical control CPU 23 is sent to the D / A converter 28 and the analog correction circuit 32. Through V
Input to the CM driver 30, and the VCM driver 30 outputs V
Supply sufficient current to the CM 17 to seek to the target track. In this way, the arm 4 having the VCM 17 mounted thereon rotates in the radial direction of the magnetic disk 8 to transfer the magnetic head 2 to the target track. The R / W gap (not shown) of the magnetic head 2 detects a magnetic change in the magnetization pattern of the recording track 40 on the magnetic disk 8, and a read voltage is generated by a coil (not shown) in the magnetic head 2.

This read voltage is amplified by the R / W amplifier 14 and then sent to the pulse detector 31 to be converted into a pulse signal. This pulse signal is sent to the servo decoder 2
9, the servo information such as the track number is read from the pulse signal. The track number read here is stored in the track register 26 and can be always referred to by the mechanical control CPU 23.

Further subsequent A and B bursts are read out,
It is sent to the peak detector 33. Upon receiving the detection command signal from the servo timing generator 25, the peak detector 33 holds the read voltage of the A and B bursts at that moment, and A
Send to the / D converter 27. Then, the A / D converter converts the held read voltage into a digital value, and the mechanical control CPU 23 reads the digital value of the A / D converter 27 and compares the magnitudes of the digital values to detect the magnetic head. The off-track amount, which is the amount of deviation from the track center, can be calculated, and fine tracking is performed based on this off-track amount to complete positioning on the desired recording track.

The read voltage read from the desired recording track is sent from the pulse detector 31 to the data processing circuit 24, converted into an NRZ signal and sent to the hard disk control CPU 21. The hard disk control CPU 21 converts this NRZ signal into digital signal data and sends it to the host system 20 to complete the read operation.

Next, the write operation of the magnetic disk drive device 37 according to the present invention will be described. When there is a data write request from the host system 20, the digital signal data is sent to the hard disk control CPU 21 of the magnetic disk drive device 37, and the data is once sent to the buffer RAM 22 and held therein. On the other hand, the hard disk control CPU 21 is the mechanical control CPU 2
A track number and a head number, which are target writing positions, are designated in 3. Then, the mechanical control CPU 23 refers to the current position of the magnetic head, calculates the seek amount to the target position, and then inputs the seek signal to the VCM driver 30 via the D / A converter 28 and the analog correction circuit 32.
Then, the VCM driver 30 supplies a sufficient current to the VCM 17 to seek to the target track, and the arm 4 carrying the VCM 17 rotates in the radial direction of the magnetic disk 8 to transfer the magnetic head 2 to the target track. When the seek to the target position of the magnetic head 2 is completed in this way, the mechanical control CPU 23 sends a signal of seek completion to the hard disk control CPU 21.

Next, the hard disk control CPU
21 reads the data from the buffer RAM 22 and outputs NR
It is converted into a Z signal and sent to the data processing circuit 24. The data processing circuit 24 encodes the NRZ signal such as 1,7RLL, and writes it on the recording track 40 of the magnetic disk 8 through the R / W amplifier 14 and the R / W gap (not shown) of the magnetic head 2. Get caught. Here, the hard disk control CPU 21 knows from the write request from the host system 20, which sector is the head and how many consecutive sectors the data is to be written, and remains when the writing of the data to one sector is completed. The number of written sectors is reduced by one, and when the number of remaining write sectors reaches zero, it is determined that writing has been completed, and a signal indicating that it is in the instruction waiting state is transmitted to the host system 20.

Next, the write operation when an off-track error occurs in the magnetic disk drive device 37 according to the present invention will be described with reference to the flowchart of FIG. Similar to the read operation described above, a write request is received from the host system 20, the head moves to the write target position in step S1, and the mechanical control CPU 23 in step S2 reads A / B which is the read voltage magnitude of the A and B bursts. By comparing the digital values of the D converter 27, the off-track amount with respect to the center position of the target recording track 40 is calculated, and it is confirmed whether or not the off-track has occurred for each sector. And the above A /
When the comparison result of the digital values of the D converter 27 exceeds the allowable value, in step S3, the mechanical control CP
U23 determines that the off-track has occurred, and the step S
At 4, the error signal is sent to the hard disk control CPU 21.

Next, in step S5, the hard disk control CPU 21 which has received the error occurrence signal
Interrupts the writing operation in step S6. Then, although the error recovery work from step S7 is started, first, the number (n) of the sector in which the error has occurred is calculated from the relationship between the head sector number for writing the data and the number of write waiting sectors. Then, the sector number (n) in which the error has occurred and the data assigned to be written in the sector number (n-1) immediately before the sector number are read from the buffer RAM 22. Next, in step S8, the hard disk control CPU 21 waits until the magnetic disk 8 rotates to a writable position in the sector number (n-1) immediately before the sector number (n) in which the error is determined to occur, In S9, when the writable position is reached, the WRITE gate is opened and the sector number (n) in which it is determined that an error has occurred
Then, the data is rewritten to each sector of the sector number (n-1) immediately before and the error recovery work is completed.

In the above embodiment, the data is rewritten from the sector immediately before the off-track error occurrence sector. However, the mechanical control CPU 23 determines that the off-track error has occurred, and the hard disk control CPU 21 determines that the error has occurred. The number of sectors to be written is compared with the required time until the hard disk control CPU 21 receives the error occurrence signal until the signal is sent, and the required time until the writing operation is suspended is added. Alternatively, the rewriting may be performed from the sector having the sector number before the error occurrence sector number by the number of the sectors. Further, in the above-described embodiment, the case where the magnetic disk drive device is controlled by two CPUs has been described, but one CPU may perform all the control.

Further, the magnetic disk device 3 according to the present invention.
7 has an ECC correction function for correcting data when an error occurs during data reading in order to improve reliability. Depending on the host system, such an EC may be used when the magnetic disk drive is started.
There is one that diagnoses the C correction function. To further explain this diagnostic test, RE from the host system
Based on the AD LONG command, the data read from the magnetic disk and the ECC information are sent to the host system. Next, the read data is rewritten by the host system so that an error intentionally occurs, and then the rewritten data and the read ECC information are rewritten on the magnetic disk. Then, data is read again from the magnetic disk by a READ command from the host system, and diagnosis is made based on whether or not an error has occurred.

Here, in the magnetic disk device 37 according to the present invention, READ LON from the host system is used.
When receiving the G command, data and EC are sent from the magnetic disk.
The C information is read at least twice each, and it is confirmed that there is no reading error by comparing the results of the first and second times, and then the read data and ECC information are sent to the host system. That is, since the diagnostic test is performed after confirming that there is no error in the data as the diagnostic test sample and the ECC information, the diagnostic test of the ECC correction function can be performed more accurately.

[0041]

As described above, according to the first means, the starting parameter table and the switching means for selecting a desired starting parameter from the outside of the apparatus are provided and the starting parameter table is connected to the host controller. In the information recording / reproducing apparatus for writing / reading the signal in response to the request from the host controller, the start-up parameter selected by the switching means is sent to the host device, which is suitable for the host system. It is possible to send parameters, and it is possible to connect to a plurality of host systems having different allowable parameters.

According to the second means, a head for writing / reading a signal to / from a recording medium in which a plurality of divided recording areas are formed on a plurality of recording tracks,
In an information recording / reproducing apparatus having means for rotationally driving a recording medium, means for positioning the head on a recording track, and means for detecting a positional deviation of the head on a target recording track, the positional deviation at the time of writing information. When the position error is detected, the information is rewritten from the recording area on the downstream side of the rotation of the recording medium from the position of the head at the time of detecting the position error, so the position error is detected even if an off-track error occurs at the time of writing. Since information is rewritten not only in the recording area but also in the recording area in which there is a risk of misregistration, it is possible to perform highly reliable writing.

[Brief description of drawings]

FIG. 1 is an explanatory diagram showing an entire magnetic disk drive device according to an embodiment of the present invention.

FIG. 2 is an explanatory diagram showing a control circuit block of a magnetic disk drive device according to an embodiment of the present invention.

FIG. 3 is an explanatory diagram showing a format of a magnetic disk of a magnetic disk drive device according to an embodiment of the present invention.

FIG. 4 is an explanatory diagram showing a startup parameter switching circuit of the magnetic disk drive according to the embodiment of the present invention.

FIG. 5 is an explanatory diagram showing off-track error recovery during writing in the magnetic disk drive according to the embodiment of the present invention.

FIG. 6 is an explanatory diagram showing an entire magnetic disk drive device as a conventional information recording / reproducing device.

[Explanation of symbols]

 13 short pin plug 18 jumper 20 host system 21 hard disk control CPU 23 mechanical control CPU 34 ROM 37 magnetic disk drive 50, 51 identification terminal

Front page continued (72) Inventor Koji Aida 1-7 Yukiya Otsukacho, Ota-ku, Tokyo Alps Electric Co., Ltd. (72) Inventor Masaaki Sato 1-7 Yukiya Otsuka-cho, Ota-ku, Tokyo Alps Electric Co., Ltd.

Claims (3)

[Claims] 1. An information recording / reproducing apparatus which comprises a start-up parameter table and a switching means for selecting a desired start-up parameter from the outside of the apparatus from the outside of the apparatus, and which is connected to a higher-order control apparatus to write / read signals. An information recording / reproducing apparatus, wherein the start-up parameter selected by the switching means is sent to the host device based on a request from the host controller. 2. The information recording / reproducing apparatus according to claim 1, wherein the parameter table has at least one of the number of logical cylinders, the number of logical heads, and the number of logical sectors. 3. A head for writing / reading a signal to / from a recording medium having a plurality of divided recording areas formed on a plurality of recording tracks, a means for rotationally driving the recording medium, and recording the head. In an information recording / reproducing apparatus having means for positioning on a track and means for detecting a positional deviation of the head on a target recording track, if the positional deviation is detected at the time of writing information, recording is performed from the head position at the time of detecting the positional deviation. An information recording / reproducing apparatus, wherein information is rewritten from a recording area on the downstream side of rotation of a medium.