JPS59231787A - Addressing system of magnetic tape - Google Patents

Abstract

PURPOSE:To increase the degree of freedom for code setting without compressing the record area of information by separating the track for record of address code from the information track. CONSTITUTION:The going information track is referred to as IT1 and the address track opposite to the track IT1 is defined as AT1. In the same way, the coming-back informtion track and the going-back address track are defined as AT1. In the same way, the coming-back information track and the going-back address track are defined as IT2 and AT2, respectively. Only information is recorded to tracks IT1 and IT2; while address codes needed for program searching are recorded to tracks AT1 and AT2. Therefore the record area of information is never compressed. At the same time, it is also possible to record data, etc. continuously and to select and read out a part of data. This also increase the degree of freedom for code setting.

Description

TECHNICAL FIELD OF THE INVENTION The present invention relates to a magnetic tape addressing system for storing information requiring cueing.

Conventional technology and problems Storage media include magnetic tape, magnetic disks, magnetic bubble memory, and IC memory, but since the amount of information such as announcement voices is extremely large, TC memory lacks storage capacity, and disk .

Bubble memory has the drawback of being too expensive. Therefore, magnetic tape is often used because it is relatively easy to use and is inexpensive.

Conventionally, in order to store multiple blocks of information (data) on a magnetic tape and select one of them to continue reading, that is, to cue, a unique code indicating the storage location is placed at the beginning of the information, as shown in Figure 3. It is common to arrange an address code (label) and read the address code (thereby knowing the starting position of the information block). However, if the address code is placed on the same track as the information in this way, a blank area (shaded area) is required to distinguish the two, which causes a reduction in the amount of information (data) that can be stored. Third
In the example shown in the figure, two tracks, forward and backward, are set on one magnetic tape, and an address code and information are recorded on each track.

Purpose of the Invention The present invention aims to increase the amount of recordable information by doubling the number of tracks and setting the information track and address track separately, and also to provide more freedom in setting the address code. It is something to do.

Structure of the Invention In the magnetic tape addressing system of the present invention, two tracks are set for one feeding direction of the magnetic tape, one track is dedicated to recording information, and the other trunk is used for recording information necessary for cueing the information. The feature is that an address code is recorded at a position, which will be explained in detail below with reference to the illustrated embodiment.

Embodiment of the Invention FIG. 1 is an explanatory diagram of a magnetic tape showing an embodiment of the invention, and shows an example in which the magnetic tape is divided into two tracks for each round trip (four tracks in total). I T + is the information truck for the outbound trip, and A
T+ is the address trunk paired with this. Similarly, I T 2 is an information track for the return trip, and Ar1 is an address track for the return trip. In the present invention, the information track ITl
', only information is recorded in IT2, and the address code necessary for cueing is the paired address trunk AT +, A
Record in r1.

That is, in the general recording method shown in +a), the information track I
Information Il+ 121 I3 . . . is continuously recorded on T+, and address codes Al, 'A2 . A3・
Record... Since the address code At corresponding to the information It precedes the information Il, the previous information 11
It is recorded alongside -1. However, address code Ai
The rear end of is the beginning of information It (boundary with information I i -1)
Consideration is necessary, such as matching the

The length of the address code Ai is the maximum of the previous information 11-
It can be extended to a length of 1, but if it is not necessary, leave a blank part BL. However, unlike in FIG. 3, this blank portion BL does not reduce the amount of recordable information.

Figure 1 (bl is a specific example of the recording method. In this example, the time O:00, o:o indicated by the timer as address code A)
s, onlo, etc. are recorded, and as information @l, for example, continuous measurement data is recorded. In this way, each part of the measurement data over time can be read out by searching for the time.

FIG. 2 is a block diagram of a device implementing the method described above.
1 is a 4-track magnetic tape, 2 is a recording/playback head for an information trunk, 3 is a recording/playback head for an address trunk, 4 is an information source, 5 is an information recording/playback section, 6 is an information output section, and 7 is a recording/playback head for an address trunk. An address code recording/reproducing section, 8 is a code discrimination circuit, 9 is a tape drive control circuit, 1o is a clock source for address codes, and 11 is an address unit control circuit for differentiating address contents.

During recording, information input Iin such as audio from the information source 4 is transferred to the information track IT+ (
clock source 10 recorded in the address unit control circuit 11 and simultaneously controlled by the address unit control circuit 11.
The head 3 records the output on the address track AT+ (or Ar1) as the address code input Ain.

Address code output A during playback. While the contents of the UT are discriminated by a code discrimination circuit 8, the tape 1 is fast-forwarded until the code given from the outside is found. When the code is detected, information is output until the next code is detected.

Plays the UT and stops when the next code is detected. The tape drive control circuit 9 controls fast forwarding, reproduction, stopping, etc. of this tape.

Effects of the Invention As described above, according to the present invention, since the track for recording the address code is separated from the information track, the information recording area is compressed by the address code itself and the blank space indicating the boundary with the information block. There will be no more trouble. It also becomes possible to record data continuously and then selectively read out only a portion of it. Further, since the length of the address code can be extended up to the length of the previous information block, there is an advantage that the degree of freedom in setting the code is increased (for example, the address can be set to an address that is easy for humans to memorize).

[Brief explanation of the drawing]

FIG. 1 is an explanatory diagram of a magnetic tape showing an embodiment of the present invention, FIG. 2 is a schematic block diagram of an apparatus implementing the method of the present invention, and FIG. 3 is an explanatory diagram of a magnetic tape showing a conventional addressing method. . In the figure, ITI and IT2 are information tracks and AT+. Ar1 is address trunk, I, Il, 12...
. is information, and A, AI, A2, . . . are address codes. Applicant Fujitsu Ltd. Representative Patent Attorney Minoru Aoyagi Figure 1 Figure 3

Claims (1)

[Claims] Two tracks are set for one feeding direction of the magnetic tape,
A magnetic tape addressing system characterized in that one track is dedicated to recording information, and the other track records an address code at a position necessary for locating the beginning of the information.