JPS62119776A - Reading controller for magnetic disk recording and reproducing device - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION "Field of Industrial Application" The present invention relates to a read control device for a magnetic disk recording/reproducing device.

"Prior Art" Conventionally, the positioning of the magnetic head of a magnetic disk recording/reproducing VcFl is performed by oven loop control.
Since a highly accurate magnetic disk feeding mechanism was required to read the recorded contents, lowering the price of magnetic disk recording and reproducing apparatuses was hindered.

"Problems to be Solved by the Invention" The present invention was made to solve the above problems, and provides a reading device that can read the recorded contents of a magnetic disk even with a magnetic head feeding mechanism with low precision. The purpose is to provide.

According to the present invention, the magnetic head is placed at a position where the pulse motor is rotated by the number of steps corresponding to the track position where the desired signal to be reproduced should be recorded. At the same time as sending the data, there is also a detection means for determining whether or not a predetermined number of sectors of data can be read at that track position, and a detection means that determines whether or not the data of a predetermined number of sectors can be read at that track position. read control of a magnetic disk recording/reproducing apparatus, comprising a moving means for sequentially moving a magnetic head in the positive and negative directions within a predetermined number of steps to perform reading again! f: position is provided.

"Operation" According to the above configuration, a predetermined number of sectors of data is read by using a magnetic head feeding mechanism that is equipped with the detection means and movement means and is capable of dividing the distance between tracks into several predetermined steps. The magnetic head can be sent to a position where it can be used.

"Example" Next, an embodiment of the present invention will be described with reference to the drawings.

@ As shown in Figures 1 and 2, in the magnetic disk recording/reproducing device [10], a feed screw 2 made of synthetic resin is attached to the sleeve of the step motor 1. The rotational movement is carried out by the feed base 4 via the feed spring 3.
The single-eared magnetic head 5 mounted on the feed base 4 is positioned by the step motor 1.

As shown in FIG. 3, for one track gap on the magnetic disk 20, a loss pulse (2
It is important that the step motor 1 and the feed screw 2 are designed so that the amount of movement of the magnetic head 5 (more than a pulse) corresponds to the amount of movement of the magnetic head 5. In this embodiment, the step motor 1 and the feed screw 2 are designed so that the rotation of the step motor 1 for four pulses corresponds to the amount of movement of the magnetic head 5 for one track gap.

As shown in FIG. 2, the magnetic disk recording/reproducing device fl
! 10 includes, in addition to the step motor 1 and magnetic head 5 described above, a magnetic disk drive circuit 11, a magnetic disk rotation motor 12. and a magnetic disk control circuit 13. And magnetic disk drive circuit 1
1 is a step motor 1 and a magnetic disk rotation motor 12 based on a command signal from a magnetic disk control circuit 13.
The magnetic head 5 starts, stops, and switches the rotational direction, and also causes the magnetic head 5 to perform operations such as recording, reproducing, and erasing. The magnetic disk control circuit 13 is connected to a computer 30 such as a personal computer. The magnetic disk control circuit 13 also includes an area (not shown) for storing a control program for controlling the operation of the magnetic disk recording/reproducing device 10, and areas 15, 18, 19, and 14a for storing various data. A memory 14 having a memory is connected thereto. The control program stored in the memory 14 is read into the computer 30 connected to the magnetic disk control circuit 13, and the computer 30 executes the control program.
Predetermined command information is transmitted from the computer 30 to the magnetic disk control circuit 13 , and the magnetic disk control circuit 13 controls the magnetic disk drive circuit 11 based on the command information from the computer 30 to drive the magnetic disk 20 through the magnetic head 5 . The magnetic disk recording and reproducing apparatus 10 is operated to record and reproduce information on the magnetic disk 20 and erase unnecessary information recorded on the magnetic disk 20. In this embodiment, a computer 30 having other functions such as a personal computer connected to the magnetic disk recording/reproducing apparatus 10 reads a control program for controlling the magnetic disk recording/reproducing apparatus 10 and directly controls the magnetic disk. Commands are issued to the circuit 13, and a computer is provided on the magnetic disk recording/reproducing device 10 side, and a personal computer or the like connected to the combinator is used as a host computer, and magnetic disk recording/reproduction is performed according to instructions from the host computer. Of course, the computer on the device 10 side may be configured to operate according to a control program stored in the memory 14.

The magnetic disk 20 has a large number of concentrically arranged tracks 21, 22, 23, 24 as shown in FIG.
．． 25... are provided, of which tracks 21, 23, 25... are write tracks, and tracks 22, 24... are erase tracks. Each write track 21, 23, 25, . . . is divided into a number of sectors 40 for recording information. In this embodiment, one track is divided into nine sectors. Erasing tracks 22, 24... are writing tracks 21, 23, 25
This is a separation band to prevent information from being mixed up. Inside the sector 40, as shown in FIG. 4, there are an ID field 41 in which information indicating the start and address of the sector is recorded, and a data field 42 in which data is recorded. and data field 42
In addition to an area where general data is written, there is also an area where a cyclic code (CRC) is written. CRC is a type of error correction code, and the length and content of data are written in a predetermined number of bytes in the CRC area. These ID field 41 and data field 42
A gap 43 is placed before and after the data to protect data from rotational fluctuations, mechanical dimensional errors, or erase date delay timing errors.

With this embodiment, even a magnetic head feeding mechanism with low precision can be used regardless of the error between the track position indicated by the dotted line 23C in FIG. 3 and the position of the magnetic head 5 fed by the step motor 1. , the ability to read information recorded on a desired track of the magnetic disk 20 will be explained as the following operation. The computer 30 reads a control program based on the chart 70 shown in FIG. 5 from the memory 14 and transmits a command signal to the magnetic disk control circuit 13.

When the step motor 1 sends the magnetic head 5 to a predetermined pulse position and a reading operation is performed, the position of the magnetic head 5 deviates from the normal track position due to errors in the installation of the feeder 2 and the step motor 1. However, in this embodiment, as shown in FIG. 6, the step motor 1 reads a predetermined number of sectors on a desired track within a predetermined range of four pulses. The magnetic head 5 is moved (stepped) in the positive and negative directions and the reading operation is performed again until the data of 40 CRCs are read.

(Operation) When the computer 30 is activated, the reseek counter 18, which determines how many times the magnetic head 5 is to be sent to a desired track position, is set to 2 in step 50 in the program shown in FIG. The value of this reseek counter 18 is decremented by 1 each time the magnetic head 5 is moved to a desired track position. In step 52,
The magnetic head 5 is sent by the step motor 1 to a pulse position corresponding to a desired track position, for example to the scan No. 0 position SO as shown in FIG.

In step 53, the retry counter 19 is entered with the number of repeated retries=5.

In step 54, the magnetic disk 20, which is the countermeasure medium, is inserted into the magnetic disk recording/reproducing device r! It is checked whether or not the magnetic disk 20 is inserted into the LIO, and if the magnetic disk 20 is inserted, the process advances to step 55. In step 55, so-called reading is performed to read the sector at the pulse position of scan No.=0.

Next, in step 57, it is determined whether the data read in step 55 was correctly read along with the CRC, and if the result is negative, the retry counter is decremented by 1 in step 58, and the process proceeds to step 59. , and when the determination result in step 57 is positive, the reading operation is terminated.

Next, in step 59, retry counter 1
It is determined whether or not 9 is zero. In the case of the example, since the try counter is 4, the process returns to step 54, and steps 54 to 58 are repeated, and if the judgment in step 59 becomes positive after 5 tries, the process proceeds to step 60. The scan number is incremented by 1.

Then, in step 61, it is determined whether the scan number is 5 or more, and in some cases, the scan number is 1.
Therefore, the judgment result is negative, so step 62
Proceed to. In step 62, scan No.
In response to =1, the magnetic head 5 is side-stepped by one pulse to the position S1 in FIG. Then, the process returns to step 53, and steps 54 to 59 are repeated with the retry counter set to 5, and step 60
Since the scan number is increased to 2 in step 61, the process returns to step 62 via step 61. This time, in step 62, tI/S3 according to scan No.=2.
The magnetic head 5 is transferred to the position S1 in the figure. In this way, by repeating steps 53 and 62, when the magnetic head 5 is moved to the pulse position of Sl in FIG. It is read by the head 5. Then, the judgment result in step 57 is NO.
Since an error occurs, the read data is transmitted to the computer 30, and at the same time, the magnetic head 5 is returned to the center position in step 63, and the process ends.

Note that when it is determined in step 61 that the scan number has become 5 or more during the repeated execution of steps 53 to 62, the reseek counter is counted down in step 64a, and the next step 6 is performed.
The judgment result is determined in step 4, and if the result is negative, the process proceeds to step 65, where the magnetic head 5 is restored, that is, the outermost track O
, and in step 51, seek is performed again,
The magnetic head 5 is aligned to pulse positions corresponding to the same track. Meanwhile, two seeks are performed and step 64
If the determination result in step 63 is positive, it is determined that the magnetic disk recording/reproducing device 10 is a defective product, and the process proceeds to step 63.
An error is displayed in a. Note that if it is determined in step 54 that there is no magnetic disk 20 as a medium, an error is displayed in step 63a.
It will be the end.

"Effects" As described above, the reading control device of the present invention has the above configuration and can read magnetic disks even with a magnetic head feeding mechanism with low precision, which reduces the cost of magnetic disk recording and reproducing devices. This has the excellent effect of achieving

[Brief explanation of drawings]

FIG. 1 is a perspective view showing the structure of a magnetic head feeding mechanism in an embodiment of the present invention, FIG. 2 is a block diagram showing a magnetic disk recording/reproducing device, FIG. 3 is a plan view showing a magnetic disk, and FIG. is an explanatory diagram showing the recorded contents in each sector,
The figure is a 70-chart showing the operating state, and FIG. 6 is a chart showing the relationship between scan numbers and step positions. 1...Step motor, 2...Feed screw, 3, 4...
...Feed spring and feed base forming a carriage, 5...Magnetic head, 10...Magnetic disk recording/reproduction f! Lr11
．． 20... Magnetic disk, 21, 22, 23, 24.
25...Truck, 30...Computer, 40.
··sector. First work by patent attorney Isamu Goto! Figure 3 Figure 4

Claims (1)

[Claims] 1. A carriage for transporting a magnetic head in the radial direction of a magnetic disk on which signals are recorded for each sector divided into a predetermined number on one track, and a feed threadedly coupled to the carriage. A magnetic disk recording/reproducing device comprising a screw and a step motor connected to the feed screw, and configured to be positioned on each track by rotating the step motor by a predetermined number of steps per track gap. In this step, the magnetic head is sent to a position where the pulse motor is rotated by the number of steps corresponding to the track position where the desired signal to be reproduced is to be recorded, and data in a predetermined number of sectors is read at that track position. a detection means for detecting whether or not the data can be read; and when the detection means detects that a predetermined number of sectors of data cannot be read, the magnetic head is rotated in the forward and backward directions within the range of the predetermined number of steps; 1. A read control device for a magnetic disk recording/reproducing device, comprising a moving means for sequentially moving in a negative direction to perform reading again.