JPH09320183A - Common to high-density/normal-density type flexible disk driving control system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To automatically control commonly used high-density/normal-density type FDD. SOLUTION: A logic circuit 100 outputs head select signals HS1, HS0, a speed select signal SS, and a position select signal PS, in response to an identification detecting signal DD from a switch unit 50. A recording/reproducing had amplifier 102 selects one of the magnetic heads, MHF1, MHF0, MHH1, MHH0, in response to the head select signal HS1, HS0. An SPM driver 120 drives and rotates a spindle motor 60, based on speed select signal SS and the FG signal. A digital signal processor 114 selects one of the carriage position signal CP and the servo signal VS, in response to the position selects signal PS, to send a position control signal PC to a VCM driver 118 based on the selected signal. The VCM drive 118 controls the current which is allowed to flow to a voice coil 17 of the voice coil motor in response to the signal PC.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to data for both a large-capacity flexible disk magnetic disk medium that rotates at high speed during recording and reproduction and a normal-capacity flexible disk magnetic disk medium that rotates at low speed during recording and reproduction. The present invention relates to a high density / normal density combined type flexible disk drive for recording / reproducing, and particularly to a control system used for the high density / normal density combined type flexible disk drive.

[0002]

2. Description of the Related Art As is well known, a flexible disk drive is a device for recording / reproducing data on / from a magnetic disk medium of a flexible disk inserted therein. In recent years, the capacity of a flexible disk has been increased, and a storage capacity of 1 M to 2 M bytes (hereinafter,
A memory having a storage capacity of 128 Mbytes (hereinafter referred to as a large capacity) has been developed in comparison with a memory having a normal capacity. Along with this, a flexible disk drive that can record and reproduce data on and from such a magnetic disk medium having a large capacity flexible disk has been developed.

Hereinafter, a flexible disk drive capable of recording and reproducing data only on a magnetic disk medium of a large-capacity flexible disk is referred to as a high-density-dedicated flexible disk drive. A flexible disk drive capable of recording and reproducing data is generally referred to as a density-only flexible disk drive. Furthermore, a flexible disk drive capable of recording and reproducing data on a magnetic disk medium of both large-capacity and normal-capacity flexible disks will be referred to as a high-density / normal-density flexible disk drive. The high-density dedicated flexible disk drive and the high-density / normal density combined-type flexible disk drive will be collectively referred to as the high-density flexible disk drive.

One of the major mechanical differences between the normal-density dedicated type flexible disk drive and the high-density type flexible disk drive is that the carriage holding the magnetic head is inserted into the flexible disk drive. The drive means is configured to move along a predetermined radial direction (radial direction of the magnetic disk medium) with respect to the disk.
That is, while a stepping motor is used as a driving means in a normal-density type flexible disk drive, a linear motor such as a voice coil motor (VCM) is used as a driving means in a high-density type flexible disk drive. I have.

The voice coil motor used as the driving means for the high-density flexible disk drive will be described in detail below. The voice coil motor is disposed behind the carriage and wound around a drive shaft parallel to a predetermined radial direction, and a magnetic circuit for generating a magnetic field crossing a current flowing through the boil coil. Having. With such a configuration, by causing a current to flow through the boil coil in a direction crossing the magnetic field generated by the magnetic circuit, a driving force is generated in the extending direction of the drive shaft based on the interaction between the current and the magnetic field. . With this driving force, the voice coil motor moves the carriage along a predetermined radial direction.

Another major difference between the normal density dedicated type flexible disk drive and the high density type flexible disk drive is the rotation of the spindle motor rotating the magnetic disk of the inserted flexible disk drive. In number. That is, in the normal density dedicated type flexible disk drive, since the flexible disk to be inserted is limited to the normal capacity flexible disk, the spindle motor for the flexible disk drive uses the magnetic disk medium of the inserted flexible disk.
It may be rotated at a low speed of rpm or 360 rpm. On the other hand, in the high density type flexible disk drive, the flexible disk to be inserted may be only the large capacity flexible disk or both the large capacity flexible disk and the normal capacity flexible disk. Therefore, when the inserted flexible disk is a large capacity flexible disk, the spindle motor for a high density type flexible disk drive drives the magnetic disk medium at a rotation speed of 3600 rpm, which is 12 to 10 times that of the normal capacity flexible disk. You have to double the speed.

Further, although there is substantially no apparent difference between the large capacity flexible disk and the normal capacity flexible disk, the large capacity flexible disk has a narrower track width (track pitch) than the normal capacity flexible disk. However, it is difficult to position the magnetic head on a desired track as compared with a normal capacity flexible disk. Therefore, a servo signal for position detection is previously written on the magnetic disk medium of the large capacity flexible disk.

Further, the high density / normal density combined type flexible disk drive needs a means for discriminating and detecting whether the flexible disk inserted therein is a large capacity flexible disk or a normal capacity flexible disk.

[0009]

Therefore, another object of the present invention is to provide a high-density / normal-density dual-purpose flexible disk drive with different spindle motor speeds based on the respective specifications, track positioning by carriage positioning, and the like. Can be identified and controlled automatically,
It is to provide a control system for a high density / normal density combined type flexible disk drive.

[0010]

According to the present invention, recording and reproduction of data is performed using a high-density magnetic head for a magnetic disk medium of a large-capacity flexible disk that rotates at high speed during recording and reproduction. High-density recording / reproduction of data using a normal-density magnetic head for a magnetic disk medium of a normal-capacity flexible disk that rotates at a low speed much lower than the high-speed during recording / reproduction
A control system used for a normal density / combined type flexible disk drive, wherein the high density / normal density / combined flexible disk drive is a spindle motor for rotating the magnetic disk medium at one of the high speed and the low speed. A carriage for holding the normal density magnetic head and the high density magnetic head; a linear motor for moving the carriage along a predetermined radial direction; and a carriage position detection signal for detecting the current position of the carriage. And a carriage position detection device for outputting a servo signal for position detection on the magnetic disk medium of the large-capacity flexible disk in advance, and the spindle motor generates an FG signal indicating its rotation speed. Means for controlling the high density /
Identification detection means for identifying and detecting whether the flexible disk inserted in the normal-density dual-purpose flexible disk drive is the large-capacity flexible disk or the normal-capacity flexible disk and outputting an identification detection signal; Selection signal generating means for generating a head selection signal, a speed selection signal, and a position selection signal in response to the high density magnetic head or the high density magnetic head in response to the head selection signal. Head selecting means for selecting one; the speed selecting signal and the FG
A spindle motor driver that rotationally drives the spindle motor based on a signal; and in response to the position selection signal, the carriage position detection signal and the magnetic head for high density from the magnetic disk medium of the large-capacity flexible disk. Position control means for selecting one of the read servo signals and outputting a position control signal based on the selected signal; and a current flowing through the coil of the linear motor in response to the position control signal. A control system for a high-density / normal-density type flexible disk drive, which has a linear motor driver for controlling;

[0011]

Embodiments of the present invention will be described below in detail with reference to the drawings.

Referring to FIG. 2, a high density / normal density combined type flexible disk drive to which the signal system and the control system according to the present invention are applied will be described. High density / normal density combined type flexible disk drive (FD
D) is a large-capacity flexible disk (HFD) described later
It is a device for recording / reproducing data on / from both the magnetic disk medium of No. 1 and the magnetic disk medium of normal capacity flexible disk (FD). Flexible disk is shown in Figure 2.
It is inserted into the high density / normal density combined type flexible disk drive from the direction indicated by the arrow A. The inserted flexible disk is held on the disk table 12 rotatably supported on the surface of the main frame 11 with their central axes aligned with each other. The disk table 12 is provided with a spindle motor (SP) embedded in a recess (to be described later) of the main frame 11.
The magnetic disk medium of the flexible disk is rotated by M) 60. A printed wiring board (not shown) on which a large number of electronic components are mounted is attached to the back surface of the main frame 11.

The high density / normal density combined type flexible disk drive is equipped with a magnetic head (described later) for reading / writing data from / to the magnetic disk medium of the flexible disk. The magnetic head is gimbal 14
It is held by the carriage 15 via. The combination of the magnetic head, gimbal 14, carriage 15, voice coil 17 (described later), FPC (flexible printed circuit), scale, spring holder, and spring is called a carriage assembly. The carriage 15 is arranged on the surface of the main frame 11 so as to be separated from the main frame 11, and allows the magnetic head to move along a predetermined radial direction (direction shown by arrow B in FIG. 2) with respect to the flexible disk. keeping.

The carriage 15 is supported and guided at its lower ends on both sides by a pair of guide bars 16 extending parallel to a predetermined radial direction B.

The carriage 15 is driven along a predetermined radial direction B by a voice coil motor (VCM) as described below. More specifically, the voice coil motor is disposed behind the carriage 15, and has a pair of voice coils 17 wound around a drive shaft parallel to a predetermined radial direction B, and intersects a current flowing through the boil coil 17. And a magnetic circuit 20 for generating a magnetic field. In the voice coil motor having such a configuration, a current is caused to flow through the boil coil 17 in a direction crossing the magnetic field generated by the magnetic circuit 20, so that the direction of extension of the drive shaft is determined based on the interaction between the current and the magnetic field. A driving force is generated. With this driving force, the voice coil motor moves the carriage 15 in the predetermined radial direction B.

FIG. 3 shows a carriage position detecting device 30 used in the high density / normal density combined type flexible disk drive shown in FIG. 3, (a) is a plan view, (b) is a left side view, and (c) is a rear view.

The illustrated carriage position detecting device 30 is a scale 3 fixedly provided on the side of the carriage 15 holding the magnetic head 13 facing the main frame 11.
1 and a photo interrupter 32 attached to the main frame 11 so as to be movable in a predetermined radial direction indicated by an arrow B. The scale 31 has a predetermined radial direction B
Slits 311 are cut at predetermined intervals along. The photo interrupter 32 includes a light emitting unit (not shown) and a light receiving unit (not shown) that are arranged to face each other with the scale 31 interposed therebetween. The light emitting portion is composed of one or a plurality of light emitting elements, and the light receiving portion is provided along the predetermined radial direction B by 90 degrees.
It is composed of four light-receiving elements arranged at a phase difference interval of °.

As shown in FIG. 3B, the carriage position detecting device 30 further includes an alignment adjusting mechanism 33 for moving the photo interrupter 32 in a predetermined radial direction B to adjust the alignment of the photo interrupter 32. . The photo interrupter 32 is provided in the opening 11a of the main frame 11, and the opening 11a has a size such that the photo interrupter 32 is moved in a predetermined radial direction B.

Returning to FIG. 2, the spindle motor 60 is mounted in a state in which it is embedded in a recess (not shown) on the surface side of the main frame 11. The spindle motor 60 has a spindle shaft 61 erected substantially perpendicular to the main surface of the main frame 11. The spindle shaft 61 is rotatably supported by the main frame 11 via a ball bearing (not shown). The spindle shaft 61 functions as a rotating shaft of a flexible disk inserted in a high density / normal density combined type flexible disk drive. The disk table 12 is fitted to the upper end of the spindle shaft 61.

FIG. 4 shows a large capacity flexible disk (HF).
D) 40 is a plan view of the back side. As shown in FIG. 4, the large-capacity flexible disk 40 has a magnetic disk medium 41 as a magnetic recording medium and a case 42 that covers the magnetic disk medium 41. A circular opening 42a is opened at the center of the back side of the case 42. A disk hub (disc-shaped metal fitting) 43 holding the magnetic disk medium 41 is loosely inserted into the circular opening 42a. The disk hub 43 has a disk center hole 43 through which the spindle shaft 61 is loosely inserted.
a and a chucking hole (disk-side drive elongated hole) 43b through which a chucking pin (drive roller) described later is loosely formed are provided at a peripheral position deviated from the disk center hole 43a.

Returning to FIG. 2 again, the disk table 12
Is longer than the diameter of the disc hub 43 and shorter than the diameter of the circular opening 42a.

The disk table 12 is provided with a table-side driving elongated hole 12a at a position corresponding to the chucking hole (disk-side driving elongated hole) 43b. The spindle motor 60 has a chucking pin (drive roller) 62 that penetrates into the chucking hole 43b through the table-side driving slot 12a. The chucking pin 62 is vertically rotatable and rotatably mounted on a magnet case 63 mounted on the lower surface of the disk table 12. A substantially rectangular parallelepiped index detecting magnet 64 is fixed to an arbitrary position on the outer surface of the outer peripheral wall of the magnet case 63.

Referring again to FIG. 4, in the case 42 of the large-capacity flexible disk 40, when viewed from the back surface side, the right corner portion at the rear end in the insertion direction (when viewed from the front surface side). A write protection hole (not shown) is formed in the left corner. FIG. 4 shows a state in which the write protection hole is closed by the write protection tab 44. The write protection tab 44 is slidable in the insertion direction. By manually operating the write protection tab 44, the write protection hole can be opened and closed. When the write-protection tab 44 closes the write-protection hole, recording is enabled, and when the write-protection hole is opened, recording is disabled.

The illustrated large capacity flexible disk 40
Has two types of storage capacity (for example, 128 MB and 25 MB
6 M bytes). A large capacity identification detection hole 45 is formed near the write protection hole.
The large capacity discriminating / detecting hole 45 is for identifying the large capacity flexible disk 40 and the normal capacity flexible disk. Further, a hole 46 for type identification detection is selectively formed near the hole for write protection together with the hole 45 for large capacity identification detection. The type identification detection hole 46 is for identifying the type of the large-capacity flexible disk 40, and the type of the large-capacity flexible disk 40 can be identified by its presence or absence. For example, the recording capacity is 12
In the case of a large capacity flexible disk of 8 Mbytes,
The type identification detection hole 46 is not formed in the case 42, and in the case of a large-capacity flexible disk having a recording capacity of 256 Mbytes, the type identification detection hole 46 may be formed in the case 42. .

Although not shown, as is well known, the large capacity discriminating detection hole 45 and the type discriminating detection hole 46 are not formed in the normal capacity flexible disk (FD).

Returning to FIG. 2, in the high density / normal density combined type flexible disk drive, further, on the printed wiring board (not shown) provided on the back surface of the main frame 11, the left corner of the rear end in the insertion direction. A switch unit 50 is mounted on the section. The switch unit 50 includes a push switch. The switch unit 50 is for detecting the write protection hole, the large capacity identification detection hole 45, and the type identification detection hole 46.

The switch unit 50 will be described in detail.
Has a write control switch 51, a large capacity identification switch 52, and a type identification switch 53. The write control switch 51 is a switch for detecting the open / close state of the write protection hole, and is provided at a position corresponding to the write protection hole. The large capacity identification switch 52 is a switch for identifying and detecting whether the inserted flexible disk is a large capacity flexible disk HFD or a normal capacity flexible disk FD, and is provided at a position corresponding to the large capacity identification detection hole 45. Has been. The type identification switch 53 is
A switch for detecting presence / absence in the type identification detection hole 46, which is provided at a position corresponding to the type identification detection hole 46.

Although not shown, the stator of the spindle motor 60 is provided with a frequency generation pattern (hereinafter abbreviated as FG pattern) for detecting the rotational speed of the stator. This FG pattern is 60 during one revolution of the spindle shaft 61 of the spindle motor 60.
Generate an FG signal with a number of pulses. As we all know,
300 rpm is equal to 5 Hz / rev, 3600 rpm
Is equal to 60 Hz / rev. Therefore, the magnetic disk medium of the normal capacity flexible disk FD is rotated by the spindle motor 60 at a prescribed rotation speed of 300r.
When rotating at pm, the FG pattern is 300 Hz F
Generate a G signal. Similarly, when the magnetic disk medium of the large-capacity flexible disk HFD is rotated by the spindle motor 60 at its specified rotation speed of 3600 rpm, the FG pattern generates an FG signal of 3600 Hz.

A control system for a high density / normal density combined type flexible disk drive according to the first embodiment of the present invention will be described with reference to FIG. As shown in FIG. 1, as the magnetic head 13, a normal density upper magnetic head MH _F1 , a high density upper magnetic head MH _H1 , a normal density lower magnetic head MH _F0, and a high density lower magnetic head. Head M
H _H0 and.

[0030] When the normal data is recorded and reproduced with respect to the magnetic disk medium capacity FD FD, usually from capacity FD controller FDC is supplied low-density write data WD _F, to the normal-capacity flexible disk controller FDC density readout data RD _F is delivered. In contrast, when data is recorded and reproduced with respect to the large-capacity flexible disk HFD of the magnetic disk medium, a high-density write data WD _H from the host device is supplied, the read data RD _H is a high density to the higher-level device Sent out.

The illustrated high-density / normal-density combined type flexible disk drive control system 100 includes a switch unit 50 (FIG. 2) and a recording / reproducing head amplifier 102.
And a normal capacity flexible disk reproducing circuit 104,
A large-capacity flexible disk recording / reproducing circuit 106,
Normal capacity flexible disk interface (FDI
/ F) 108, logic circuit 110, large capacity flexible disk controller and interface (HDC)
I / F) 112 and digital signal processor (D
SP) 114, operational amplifier 116, voice coil motor driver (VCM driver) 118, and spindle motor driver (SPM driver) 120.
Logic circuit 110 includes a data selector 110a. The digital signal processor 114 is an A / D converter 114
a and a D / A converter 114b.

The recording / reproducing head amplifier 102 is provided on the carriage 15 (FIG. 2) which holds the normal density magnetic heads MH _F1 and MH _F0 and the high density magnetic heads MH _H1 and MH _H0 . The recording / reproducing head amplifier 102 reads the data read by the normal-density magnetic heads MH _F1 and MH _F0 and the high-density magnetic heads MH _H1 and MH _H0 , respectively. In addition to amplifying the amplified data, the normal density magnetic heads MH _F1 and MH _F0 and the high density magnetic heads MH _H1 and MH
Supply amplified data to _H0 .

Normal capacity flexible disk reproducing circuit 1
04 and the large-capacity flexible disk recording / reproducing circuit 106 are provided on a wiring board (not shown) different from the carriage 15. The normal capacity flexible disk reproducing circuit 104 uses the normal density read amplified data for the MFM.
Play according to the modulation and demodulation method. The large-capacity flexible disk recording / reproducing circuit 106 reproduces the high-density read amplified data according to the 1-7 RLL modulation / demodulation method, and at the same time, the high-density flexible disk controller and the high-density write data WD _H from the interface 112 is 1-7.
Data selector 11 is modulated according to the RLL modulation / demodulation method.
Send to 0a.

Normal capacity flexible disk reproducing circuit 1
The data reproduced in 04 is sent to the normal capacity flexible disk controller 200 via the normal capacity flexible disk interface 108. Meanwhile, the low-density write data WD _F from capacity FD controller 200 data selector 110
It is sent to the recording / reproducing head amplifier 102 via a.

The data reproduced by the large-capacity flexible disk recording / reproducing circuit 106 is sent to the host device as high-density read data RD _H via the large-capacity flexible disk controller and interface 112. On the other hand, high-density write data WD _H from the host device
Is sent to the large-capacity flexible disk recording / reproducing circuit 106 via the large-capacity flexible disk controller / interface 112, modulated by the large-capacity flexible disk recording / reproducing circuit 106 in accordance with the 1-7RLL modulation / demodulation method, and then the data selector 110a. To the recording / reproducing head amplifier 102 via the.

Logic circuit 100 (data selector 110
a) is an identification detection signal DD for identifying and detecting whether the flexible disk inserted in the high density / normal density combined type flexible disk drive from the switch unit 50 is the large capacity flexible disk HFD or the normal capacity flexible disk FD. receive. When the identification detection signal DD indicates that the normal capacity flexible disk FD has been identified and detected, the data selector 110a selects the normal density write data WD _F from the normal capacity flexible disk controller 200, and the recording / reproducing head. It is sent to the amplifier 102. On the other hand, when the identification detection signal DD indicates that the large-capacity flexible disk HFD is identified and detected, the data selector 110a selects the modulated data from the large-capacity flexible disk recording / reproducing circuit 106 to record / reproduce. It is sent to the head amplifier 102.

The logic circuit 100 sends the head select signals HS1 and HS0 to the recording / reproducing head amplifier 102 in response to the identification detection signal DD. The recording / reproducing head amplifier 102 selects one of the magnetic heads MH _F1 , MH _F0 , MH _H1 , and MH _H0 in response to the head select signals HS1 and HS0. Further, the logic circuit 100 sends the speed selection signal SS to the SPM driver 120 in response to the identification detection signal DD. The SPM driver 120 determines the spindle motor 6 based on the speed selection signal SS and the FG signal.
0 is rotationally driven.

When the inserted flexible disk is a normal capacity flexible disk FD, the carriage position detection signal CP detected by the carriage position detection device 30 is sent to the A / D converter 114a of the digital signal processor 114 via the operational amplifier 116. Supplied. on the other hand,
If the inserted flexible disk is a large capacity flexible disk HFD, a large capacity flexible disk H
The servo signal SV written on the FD magnetic disk medium is read by the high-density magnetic head MH _H1 or MH _H0 , and a digital signal is sent via the recording / reproducing head amplifier 102 and the large-capacity flexible disk recording / reproducing circuit 106. A / D converter 114a of processor 114
Is supplied to. The logic circuit 110 sends the position selection signal PS to the digital signal processor 114 in response to the identification detection signal DD. The digital signal processor 114 selects one of the carriage position detection signal and the servo signal in response to the position selection signal PS,
The position control signal PC is sent to the VCM driver 118 based on the selected signal. The VCM driver 118 responds to the position control signal PC to control the current flowing through the voice coil 17 of the voice coil motor.

As described above, in the present embodiment, the high density / normal density combined type flexible disk drive can be automatically controlled in response to the identification detection signal DD from the switch unit 50.

[0040]

As is apparent from the above description, according to the present invention, it is determined whether the flexible disk inserted in the high density / normal density combined type flexible disk drive is a large capacity flexible disk or a normal capacity flexible disk. Identification detection means for performing identification detection and outputting an identification detection signal; selection signal generation means for generating a head selection signal, a speed selection signal, and a position selection signal in response to the identification detection signal; and in response to the head selection signal A head selecting means for selecting one of the high density magnetic head and the high density magnetic head; based on the speed selection signal and the FG signal,
A spindle motor driver for rotationally driving a spindle motor that rotates a magnetic disk medium of a flexible disk; a carriage position detection signal from a carriage position detection device in response to a position selection signal, and a high-density magnetic head Position control means for selecting one of the servo signals read from the magnetic disk medium and outputting a position control signal based on the selected signal; and a current flowing through the coil of the linear motor in response to the position control signal. And a linear motor driver for controlling the., The high density / normal density combined type flexible disk drive can be automatically controlled.

[Brief description of drawings]

FIG. 1 is a block diagram showing a control system for a high density / normal density combined type flexible disk drive according to an embodiment of the present invention.

FIG. 2 is a plan view showing a high density / normal density combined type flexible disk drive to which the high density / normal density combined type flexible disk drive control system shown in FIG. 1 is applied.

3A and 3B are views showing a carriage position detecting device used in the high density / normal density combined type flexible disk drive shown in FIG. 2, in which FIG. 3A is a plan view, FIG. 3B is a left side view, and FIG. Is a rear view.

4 is a plan view of a large-capacity flexible disk accessed by the high-density / normal-density dual-purpose flexible disk drive shown in FIG. 2, as viewed from the back side.

[Explanation of reference numerals] 13 magnetic head 17 voice coil of voice coil motor (VCM) 30 carriage position detection device 31 scale 32 photo interrupter 50 switch unit 60 spindle motor 100 high-density / normal-density combined use type flexible disk drive signal system 102 recording / Playback head amplifier 104 Normal capacity flexible disk playback circuit 106 Large capacity flexible disk recording / playback circuit 108 Normal capacity flexible disk interface (FD I / F) 110 Logic circuit 110a Data selector 112 Large capacity flexible disk controller and interface (HDC I / F) F) 114 digital signal processor (DSP) 114a A / D converter 114b D / A converter 116 operational amplifier 118 Scan coil motor driver (VCM driver) 120 spindle motor driver (SPM driver) 200 capacity FD controller (FDC) FD capacity FD HFD large-capacity FD

Front page continued (72) Inventor Takafumi Seto 1601 Sakai, Atsugi, Kanagawa Mitsumi Electric Co., Ltd. Atsugi Plant

Claims (1)

[Claims] 1. A high density magnetic head is used to record and reproduce data on a magnetic disk medium of a large-capacity flexible disk that rotates at a high speed during recording and reproduction, and at the time of recording and reproduction, it is much higher than the high speed. It is a control system used for a high-density / normal-density flexible disk drive that records / reproduces data using a normal-density magnetic head even for a magnetic disk medium of a normal-capacity flexible disk that rotates at a low low speed. The high density / normal density combined type flexible disk drive is
A spindle motor that rotates the magnetic disk medium at one of the high speed and the low speed, a carriage that holds the normal density magnetic head and the high density magnetic head, and the carriage in a predetermined radial direction. A linear motor that moves along with a carriage position detecting device that detects the current position of the carriage and outputs a carriage position detection signal, and a servo signal for position detection on the magnetic disk medium of the large capacity flexible disk. Is written in advance, the spindle motor includes means for generating an FG signal indicating the rotation speed of the spindle motor, and the control system is configured such that the flexible disk inserted in the high density / normal density combined type flexible disk drive has the large size. Capacity flexible disk or normal capacity flexible disk And a selection signal generating means for generating a head selection signal, a speed selection signal, and a position selection signal in response to the identification detection signal; Head selecting means for selecting one of the high density magnetic head and the high density magnetic head in response to a selection signal;
A spindle motor driver that rotationally drives the spindle motor based on the speed selection signal and the FG signal; and a large capacity by the carriage position detection signal and the high-density magnetic head in response to the position selection signal. Position control means for selecting one of the servo signals read from the magnetic disk medium of the flexible disk and outputting a position control signal based on the selected signal; and the linear controller in response to the position control signal. A control system for a high density / normal density type flexible disk drive, comprising: a linear motor driver that controls a current flowing through a coil of a motor.