JPH04105210A - Magnetic tape device - Google Patents

Abstract

PURPOSE:To designate the repeat number of times f cleaning and cleaning time per one time of cleaning arbitrarily by providing a program by which head cleaning with cleaning time setting the repeat number of times as upper limit only when the time is within the maximum rating is performed. CONSTITUTION:A host, when being started up from a key board 3, issues a cleaning (CLEANING) command. A magnetic tape device 5 executes cleaning routine when receiving the command. In other words, the cleaning command in which the repeat number of times of cleaning and the cleaning time per one time of cleaning are set is received, and it is decided whether or not the repeat number of times of and the cleaning time are within the maximum rating, and the head cleaning with the cleaning time per one time is performed setting the repeat number of times as the upper limit only when it is decided that they are within the maximum rating. In such a way, it is possible to designate the repeat number of times of cleaning and the cleaning time per one time on a magnetic head arbitrarily.

Description

[Detailed Description of the Invention] [Summary] Regarding a magnetic tape device that cleans the head using a cleaning tape, the first object is to enable arbitrary designation of the number of cleaning repetitions and the duration of one cleaning. ,
The second purpose is to be able to automatically judge whether the cleaning results are good or bad. The configuration includes a program that determines whether or not each tape is within the maximum rating, and only when it is within the maximum rating, performs head cleaning for the cleaning time each time with the number of repetitions as the upper limit. A cleaning tape is housed in an autochanger, and the automatic changer is configured to have a brochure ram that alternately performs head cleaning using the cleaning tape and determining the quality of cleaning results using the normal tape.

(Industrial Application Field) The present invention relates to a magnetic tape device that cleans a head using a cleaning tape.

When magnetic tape is used as an external storage medium in a computer system, it is not desirable if errors occur in read or write data due to dirt on the magnetic head, so the head must be cleaned periodically.

(Prior Art) It is necessary to use a cleaning tape for a magnetic head while considering the recommended cleaning time within a range that does not exceed the maximum cleaning time and maximum number of repetitions listed in the column of how to use the cleaning tape. Conventionally, the following methods have been adopted.

■The operator manages the time the cleaning tape is in the PLAY state, and when the cleaning time reaches the rated (maximum recommended) time, operates the EJECT button to end the cleaning.

In this method, the number of times of cleaning is also managed by the operator.

■The target value of cleaning time is stored in firmware in the magnetic tape device in advance, and when the actual cleaning time reaches that value, the cleaning tape is automatically ejected.
Do T.

[Problems to be Solved by the Invention] The above-mentioned method (1) has the disadvantage that the cleaning time and the number of repetitions are manually managed, resulting in large errors and that it is easy to use the method incorrectly.

On the other hand, although the cleaning time can be managed accurately in the method (2), it has the disadvantage that the cleaning time cannot be changed depending on the degree of dirt on cleaning tapes or heads with different ratings. Furthermore, the number of repetitions is determined manually and therefore becomes inaccurate.

The first purpose of the present invention is to enable the number of cleaning repetitions and the time for one cleaning to be arbitrarily specified, and the second purpose is to enable automatic determination of the quality of cleaning results. It is said that

(Means for solving the problem) FIG. 1 is a block diagram of the present invention, where l is a host computer,
2 is the display, 3 is the keyboard, 4 is the pass line (
5 is a magnetic tape device as an external storage device, and 6 is a hard disk device shown as an example of another external storage device.

[Operation] When the host 1 is activated from the keyboard 3, it issues a cleaning (CLEAN ING) command as shown in FIG. The command in the figure has a 6-byte structure, and the 0th byte is an operation code. This is also used to specify read/write, etc., but here the second and third bits are 1 for cleaning.

The LUN in the first byte is logical unit number 8, which specifies the magnetic tape device 5. The third byte is the number of cleaning repetitions M1, and the fourth byte is the time T for one cleaning. The values of M and T can be set arbitrarily from the keyboard 3. The cleaning time T can be specified in seconds. The number of repetitions M indicates the maximum number of times this command is input until the magnetic tape can be accessed normally by repeating cleaning. In other words, it is an instruction for the maximum number of times to repeat cleaning.

When the magnetic tape device 5 receives this command, it executes a cleaning routine. This routine cleans the head when the cleaning tape is inserted manually, and automatically ejects the cleaning tape when one cleaning time T has elapsed, and counts the number of times this command is input (I). It's about remembering it.

Therefore, the cleaning time T and the number of repetitions M (that is, the number of times I input the cleaning command) can be automatically managed.

In this first method, it is necessary to manually insert the cleaning tape and to check the read/write operation by inserting a normal tape to determine the quality of the result after one cleaning. The second method uses an autochanger to automate this process.

In this second method, a cleaning tape and a normal tape are pre-loaded into an autochanger, and the cleaning tape is automatically transferred to a tape deck during cleaning and replaced with a normal tape during a check. Therefore, manual work is significantly reduced.

[Embodiment] FIG. 3 is a flowchart of a first embodiment of the present invention, showing a cleaning routine for five examples of magnetic tape devices. This routine performs CLEAN in the first step Sl.
The ING command is input, and in the next step S2, the number of repetitions M specified by the command is compared with the maximum rating stored in the device itself.

Then, since it is normal when M≦maximum rating, the cleaning time T is compared with the maximum rating in step S3. This is also normal if T≦maximum rating, so in step S4 the number of inputs of the CLEANING command I (initial value 0) is incremented, and the process moves to steps 35 and below. In this step S5, M and I are compared, and if M≧1, it is within the number of repetitions, so the insertion of the cleaning tape is waited for in step S6. If the cleaning tape is inserted here, the process waits for the PLAY state in step S7, and then waits for the end of the cleaning time T in step S8. If it is determined that T has ended here, one cleaning has been completed, so step S9. Eject the cleaning tape automatically using SIO. Then step 31
In step S1, a GOOD status is returned to the host to indicate cleaning completion, and in step S12, a GOOD status is returned to the host.
After returning D COMPLETE (command execution completed), in step 313, Bus Free (bus free)
Move to phase.

Host 1 that received COMMAND COMPLETE
Since the CLEANING command is issued again, the magnetic tape device 5 starts processing from step Sl again. If this process is repeated, M<1 will eventually be reached in step S5, so in this case, the process branches to step S14, decrements ■, and further, in step S15, CHECK C0
Returns the NDITION status. This status indicates that there is an error, which is determined by M> in step S2.
It is also returned when the maximum rating is reached and when T>maximum rating in step S3.

Note that when the cleaning time T is specified as 0, the EJECT operation is performed immediately without cleaning. Also,
This command is valid only when the cleaning tape is not on the logical unit, so if it is on the logical unit, CHECK C0NDIT is sent when this command is received.
Returns ION status.

FIG. 4 is a flow chart of a second embodiment of the present invention.

In this example, there is a cleaning table T inside the magazine as shown in Figure 5.
The present invention is directed to a magnetic tape device 5 in which a tape deck 52 is combined with an autochanger 51 accommodating a tape P and a normal tape TP'.

Steps S1 to S3 in Fig. 4, 311 to S13゜S15
is the same as in FIG. 3, and steps 320 to S29 are the fourth step.
This is a process specific to diagrams. That is, in this example, the CLEA in FIG.
Instead of incrementing the number of NrNG command inputs I, the number of repetitions M is decremented from the initial value M in step S29, and whether or not it has become 0 is determined in step S2.
Determine with 0. If it is not 0, a cleaning tape is inserted in step 321, and the end of the cleaning time T is waited for in the next step S22. When T ends, step S2
In step 324, the cleaning tape is ejected into the magazine of the autochanger 51, and instead, in step 324, a tape for medium access is inserted from the magazine. Then, data is written on this tape in step S25, and if it is determined in step 326 that writing has been performed normally, the written data is read out in step S27. If it is determined in step 32B that reading has been performed normally, the head has been sufficiently cleaned, so step S
At 11, the Good status is returned. However, if it is determined in step 328 that there is an error, M is decremented in step S29 and cleaning is performed again. If a data error is detected even after repeating this cleaning M times, the process branches from step S20 to step 315 and ends.

This second method not only does not require manual tape replacement, but also the host side only needs to issue a cleaning command (no need to issue a REET/WRITE command), which has the advantage of reducing the burden on both parties. .

〔Effect of the invention〕

As described above, according to the present invention, it is possible to arbitrarily specify the number of repetitions of cleaning for the magnetic head and the time for one cleaning, and the quality of cleaning results can be automatically judged by using an autochanger. There is an advantage that it can be done.

[Brief explanation of the drawing]

Fig. 1 is a configuration diagram of the present invention, Fig. 2 is an explanatory diagram of cleaning commands, Fig. 3 is a flowchart of the first embodiment of the invention, and Figs. 4 and 5 are diagrams of the second embodiment of the invention. FIG. 2 is a flowchart and a configuration diagram. There is a cleaning tape. TP' is an ordinary tape Applicant: Fujitsu Ten Co., Ltd. Representative Patent Attorney Aoyagi During twisting, 1 is the host computer, 3 is the keyboard, 4 is the pass line,
5 is a magnetic tape device, 51 is an autochanger, 52 is a tape deck, and TP auto-changer/jv51 is a block diagram of the present invention.FIG. 1 is a block diagram of a second embodiment of the present invention.Explanatory diagram of the CLEANING command.FIG.

Claims (1)

[Claims] 1. Receives a cleaning command in which the number of cleaning repetitions (M) and one cleaning time (T) are arbitrarily set, and whether the number of repetitions and cleaning time are both within the maximum rating. A magnetic tape device comprising a program that determines whether or not the head cleaning is performed, and performs head cleaning for the cleaning time each time with the number of repetitions as the upper limit only when the number of times is within a maximum rating. 2. Regular tape (TP') and cleaning tape (T
2. The magnetic tape device according to claim 1, further comprising a program for alternately performing head cleaning using the cleaning tape and determining the quality of cleaning results using the normal tape.