JPS61158081A - Cartridge type magnetic tape device - Google Patents

Abstract

PURPOSE:To attain the use of a magnetic tape with different length by adopting the constitution that an identification mark representing a length of magnetic tape is recorded in a prescribed position of the magnetic tape and the identifica tion mark is read at the initial operation. CONSTITUTION:A caption BS indicates a burst (identification mark). The burst exists at a prescribed position, e.g., on the 1st track apart from a BPT by a prescribed interval and information relating to the length of magnetic tape is written magnetically in the burst. When the content of the burst is, e.g., '00', it indicates that the magnetic tape has a length of Lm. When the content of the burst is '10', it depicts that the magnetic tape has a length of 2Lm. A magnetic tape controller reads the content of the burst BS at the initial operation to identify the length of magnetic tape.

Description

Detailed Description of the Invention [Field of Industrial Application] The present invention provides a burst (identification mark) indicating the tape length in a specific area of a magnetic tape, and automatically reads this during the initial operation. The length of the magnetic tape is recognized, the magnetic tape is divided into the beginning part, the middle part, and the end part, and if BOT is not detected at the beginning part of the tape or a hole is detected in the middle part of the tape, EO is performed at the end part of the tape.
This invention relates to a cartridge type magnetic tape device that recognizes that an error has occurred when T is not detected.

[Conventional technology and problems]

FIG. 2 is a diagram showing an outline of a magnetic tape. In Figure 2, TP is a magnetic tape, BOT is a tape start mark,
EOT indicates the end of tape mark. B.O.
T and EOT are the holes in the diameter section and define the range of use of the tape.

The cartridge type magnetic tape device uses the serpentine method. FIG. 3 is a diagram for explaining the serpentine system. In FIG. 3, DT indicates a data track. The magnetic tape is of three tracks. In a serpentine cartridge type magnetic tape device, when reading or writing, for example, the first data track DT is read/written while driving the tape so that the magnetic head moves rightward, and the EOT is read/written. When BOT is reached, the magnetic tape drive direction is switched, and while the tape is driven so that the magnetic head moves to the left, the second data track DT is read/written.When BOT is reached, the magnetic tape drive direction is changed. Then, the third data track DT is read/written while driving the tape so that the magnetic head moves rightward.

Thereafter, similar operations are repeated.

By the way, as shown in FIG. 4, a magnetic tape has a predetermined range from the beginning of the tape as a start end, a predetermined part from the end of the tape as an end part, and the remaining part as an intermediate part, and a BO is placed at the start end.
A cartridge-type magnetic tape device is known that recognizes that there is a fault in the tape when T is not detected, EOT is not detected at the end portion, or a hole is detected in the intermediate portion. In addition, in FIG. 4, the hatched portion indicates the intermediate portion. However, this type of conventional cartridge type magnetic tape device has the disadvantage that it can only use fixed length magnetic tape and cannot use magnetic tapes of different lengths as shown in FIG.

[Purpose of the invention]

The present invention is based on the above consideration, and the present invention is based on a cartridge type magnetic tape that divides a magnetic tape into a beginning part, an intermediate part, and an end part, and detects a failure based on whether or not a predetermined event is detected for each part. The purpose of this invention is to enable a control device to easily recognize the length of a magnetic tape in a tape device.

[Means to achieve the purpose]

For this reason, the cartridge-type magnetic tape device of the present invention uses a serpentine-type cartridge-type magnetic tape device that divides the magnetic tape into a beginning part, a middle part, and a tail part, and performs error processing when a hole is detected in the middle part. The tape device is characterized in that an identification mark indicating the length of the magnetic tape is recorded at a predetermined position on the magnetic tape, and the identification mark is read at the time of initial operation.

[Embodiments of the invention]

Hereinafter, the present invention will be explained with reference to the drawings. FIG. 1 is a diagram illustrating one embodiment of the present invention. In Figure 1,
BS indicates a burst (identifier va). The burst starts at a predetermined location, e.g., at a certain distance from the BOT.
It exists on the track, and information regarding the length of the magnetic tape is magnetically written therein. For example, if the burst content is [00J, it indicates a magnetic tape with a length of Lm, and if the burst content is "10", it indicates a magnetic tape with a length of 2Lm. The magnetic tape control device reads the contents of the burst BS during initial operation, recognizes the magnetic tape length, and selects a predetermined portion from the beginning of the tape as the start end, a predetermined portion from the end of the tape as the end portion, and the rest as the intermediate portion. Define. Then, the magnetic tape control device reports to the host computer that there is a failure if a BOT is not detected at the start end, performs the same process when a hole is detected at the middle end, and detects an EOT at the end end. Similar processing is performed even if it is not done.

〔Effect of the invention〕

As is clear from the above description, the present invention provides a cartridge-type magnetic tape that divides a magnetic tape into a beginning part, an intermediate part, and an end part, and detects a failure based on whether or not a predetermined event is detected for each part. In a tape device, a remarkable effect can be achieved in that magnetic tapes of different lengths can be used.

[Brief explanation of the drawing]

Figure 1 is a diagram explaining one embodiment of the present invention, Figure 2 is a diagram showing an overview of a magnetic tape, Figure 3 is a diagram explaining the serpentine system, and Figure 4 is a diagram showing magnetic tapes of different lengths. FIG. TP...magnetic tape, DT...data track,
BS...burst, BOT...tape start mark,
EOT... Tape end mark.

Claims (1)

[Claims] Divide the magnetic tape into a beginning part, a middle part, and an end part,
In a serpentine cartridge type magnetic tape device that performs error processing when a hole is detected in the intermediate portion, an identification mark indicating the magnetic tape length is recorded at a predetermined position on the magnetic tape, and the above identification mark is recorded at a predetermined position on the magnetic tape. A cartridge-type magnetic tape device configured to read an indicator.