JPS6032242B2 - file device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a file device in which a magnetic disk surface is divided into a plurality of sectors, and the capacity of the sectors is variably controlled by a servo surface to write and file recorded information.

Conventionally, file devices for recorded information consisting of a plurality of magnetic disk surfaces and a servo surface for controlling the disks use a variable file method in which the length of several records within one track, that is, the length including addresses and data, is variable; It is classified into a sector file system in which the track is divided into several fixed lengths.

This sector file system has the following advantages over the variable file system. That is, in the sector file method, a file device searches for m processing target sectors, and since the data length is constant, the control device can be small-sized. (1) Since reading and writing in one sector is one unit, it is not necessary to write most of one track each time the format is written, unlike in the variable file method, and the time dedicated to the file can be reduced. [3-Due to defects on the magnetic disk surface, the inconvenience does not affect the entire track, but only one sector. As mentioned above,
This is more advantageous than the variable file method as a file method that handles a large amount of data in the same format. However, since the data length is fixed, there may be many overflows depending on the file contents, or the usage efficiency within one sector may be low, and there is an essential drawback that it cannot efficiently handle cases where the record lengths are significantly different. SUMMARY OF THE INVENTION An object of the present invention is to provide a file device that can cope with the case where the record length varies greatly depending on the file contents. In order to achieve the above object, the file device of the present invention is a file device that divides a magnetic disk surface into a plurality of sectors and controls them with a servo surface to write and output recorded information. The present invention is characterized by comprising means for writing a sector signal so that the sector capacity corresponds to the file capacity to be written.

The present invention will be described in detail below with reference to examples.

The figure is an explanatory diagram showing the configuration of an embodiment of the present invention.

In the figure, a servo surface 1 uses one surface of a plurality of magnetic disks provided on the same side of the file device, and a servo head 2 that can move in the radial direction is provided facing the servo surface, and a servo head 2 is provided via a preamplifier 3 to control the servo. It is possible to commonly control a plurality of concentrically rotating magnetic disks by detecting servo information pre-recorded on the surface. In this case, the servo signal is recorded based on the index 12o of one point on the circumference. Conventionally, sectors are divided by signals recorded on the servo surface, and the servo head 2 only detects the signals and cannot change them. In the present invention, for example, a writing head 13 for exclusive use of sector signals is provided facing the circumferential edge 11 of the servo surface 1 in the same direction as the servo head 2, and a write control signal is sent from the CPU 20 to the controller 21 via the preamplifier 14. is given and a sector signal is written. The sector signal has index 12o as the basic position, and sector division positions 12, 122, 123, etc. are equally spaced from there.
12n. The sector signal requires about 7 to 8 bits for signal detection and sector number discrimination. The sector capacity is variably set in advance by a program according to the file contents. That is, as shown in the figure, a sector signal write command is given from the CPU 20 to the control device 21, and the control device 21 receives and synthesizes the control signals of the sector signal generators 3 and servo signals in response to the sector signals. supply. It synchronizes with the servo signal using the servo synchronization circuit 31 inside the sector signal generator.
Index 12 detected in servo head 2 by counter and decoder 32. The sector signal generator 33 counts count values 0 to n indicating a constant sector interval from
12. A sector signal is generated by inputting the sector signal into a preamplifier 14, and then a sector signal dedicated head 13 performs a sector-by-sector alignment 12. ，
Write to 122, 123..., 12n. For example, if a track has 40,000 bytes per lap and is divided into 8 sectors, each sector has 500 bytes, but 10
A sector has 400 ruits, and 16 sectors has 250 ruits, so it can efficiently handle various data contents. As explained above, according to the present invention, in the sector file system, a write head dedicated to the index sector signal is provided on the servo surface to enable writing, and the capacity of one sector is made variable, thereby changing the file contents. Since the sector capacity can be programmed according to the sector capacity, it is possible to avoid the disadvantages of data length overflowing from one sector or conversely short data length resulting in usage efficiency of 4.0%. You can choose.

[Brief explanation of the drawing]

The figure is an explanatory diagram showing the configuration of an embodiment of the present invention, and in the figure,
1 is the servo surface, 2 is the servo head, 3 is the preamplifier, 1
1 is the edge along the circumference, 12o is the index position, 12,
~12n is a sector division position, 13 is a sector signal dedicated head, 14 is a preamplifier, Futagawa CPU, 21 is a control device, 30 is a sector signal generator, 31 is a servo synchronization circuit,
32 is a counter and decoder, and 33 is a sector signal generator.

Claims (1)

[Claims] 1. A file device that writes and reads recorded information by dividing a magnetic disk surface into a plurality of sectors and controlling them with a servo surface, which has a sector capacity corresponding to the file capacity to be written on the servo surface. 1. A file device comprising means for writing a sector signal to a file.