JPS5954016A - Rewriting system of recorded mark - Google Patents

Abstract

PURPOSE:To improve the success factor of rewriting, by rewriting a recording mark on a magnetic tape with a shift from a marker BOT showing the initiation of the tape. CONSTITUTION:If the writing fails for both recording density mark ID and gain control mark ARA, a magnetic tape MT is rewound. At the same time, the skip discrimination data SKP of a low frequency is written to all tracks with a high current and a prescribed length. Then the marks ID and ARA are written again from the position where an IBG longer than a fixed length is written. If it is impossible to write normally the marks ID and ARA even with above-mentioned rewriting, the tape MT is rewound again. Then the data SKP is writte in double length to perform the similar processing. As a result, the success factor is improved for rewriting.

Description

DETAILED DESCRIPTION OF THE INVENTION TECHNICAL FIELD OF THE INVENTION The present invention relates to a rewriting method when writing a recording mark to a magnetic tape fails.

Conventional technology and problems Magnetic tapes that record digital data have an ID indicating the recording density and an AR marker for automatic gain adjustment of the reading amplifier.
A (Automatic Recognition
Amplifier) burst, etc. are written. These marks are collectively called recording marks and are written at the beginning of the magnetic tape, but their position is at the beginning of the tape where the silver paper (marker) BOT indicating the beginning of the tape is pasted on the back side by a machine or manually. The magnetic surface is likely to be stained or damaged due to the pasting operation, and as a result, recording marks may not be written normally. The recording mark is an ID that is read-after-written and written to one channel out of multiple channels.

Subsequently, the ARA burst written to all channels is read as scheduled and the write is confirmed to be normal, but if a dropout occurs, it is a write error.
In this case, the retry is performed by software or by hardware, that is, by the magnetic tape control device.

However, if the tape is scratched, it will not be possible to write normally even if you retry, and even if you repeatedly read and write, the result will be an error. Therefore, the retry is aborted after an appropriate number of times, and a tape replacement is instructed. When this happens, conventional methods have to rely on manual operations such as cutting a part of the magnetic tape and reattaching the BOT marker, or disposing of the tape.

Naori OT markers are attached to reel-to-reel magnetic tape, and cassette tapes have a connecting boundary between the transparent tape part and the magnetic part at the beginning of the tape, and this becomes the BOT marker, so there is no need to attach BOT II paper. .

Therefore, if the cassette tape has an abnormality at the boundary, it is not possible to make it usable by reattaching the BOT.

Purpose of the Invention The present invention provides that, when a recording marker cannot be written normally in a BOT marker part, a dummy signal (identification data) indicating a skip is written in the part, and then a position This is an attempt to write a record marker by shifting the .

In this way, there is no need for manual processing such as reapplying the BOT marker, and it can also be effectively used for cassette tapes and the like.

Structure of the Invention The present invention provides automatic rewinding when writing a recording marker on a magnetic tape fails in a recording marker rewriting method on a magnetic tape medium in a system equipped with a magnetic tape control device and a magnetic tape device. Then, predetermined skip identification data is written over the area where the writing failed, and an IBG of a certain length is written.
The recording marker is characterized in that the recording marker is written again after it is created, and this will be explained in detail below with reference to the illustrated embodiment.

Embodiment of the Invention FIG. 1 is a block diagram showing an embodiment of the invention, FIG. 2 is an explanatory diagram of rewriting operation, and FIG. 3 is a rewriting processing flow. First, an overview of the operation will be explained with reference to FIG. This figure is an explanatory diagram of the leading part of the magnetic tape MT, where BD is the boundary between the transparent surface and the magnetic surface, and BOT is the aforementioned marker affixed to the back side of the tape magnetic surface. It will be done. R is a playback head, W is a recording head, and these heads are at the positions shown when the tape is stopped by BOT or BD core detection by a photoelectric sensor. Figure (a) shows the recording density indicator ID and AR in the first writing.
A mark 1liI! (for one trunk) could not be written normally. This can be immediately determined by reading out the signal written by the recording head W with the reproducing head R. The x mark in the figure indicates an area where no signal is detected. In the present invention, the recording mark ID
, if the writing of ARA fails, the magnetic tape MT is rewound and the low frequency skip identification data SKP is written as shown in (b).
is written to all tracks with high current for a specified length (all tracks ON).
writing). And I BG (Intern) above a certain level
Record mark TD again from the position where Al Block Gap) was written.

Write ARA. By this rewriting, the indicator ID, A
If the RA cannot be written normally, the magnetic tape MT is rewound again, the skip identification data SKP is written to twice the length, and the same process is performed. If the marker ID and ARA can be written normally eventually, or if an area where the marker ID and ARA can be written normally cannot be found even after writing the skip identification data SKP and IBG N times (for example, 10 times), process. end.

FIG. 3 shows the flow of this write process, which is performed by the MTC control section 1 of FIG. 1. To start writing, check whether the load point is located (where the BOT is) and select YES.
If so, give a running instruction and write II) to the specified length. If the writing of this ID indicator is detected as abnormal by the MTC control unit 1, an instruction to stop the tape drive is given to the magnetic tape device drive circuit 16, a check is made to see if the tape drive has stopped more than a specified number of times, and NO is detected.
If so, a rewind instruction is given to the magnetic tape control information circuit 5. Then, the magnetic tape device 18 rewinds 1, oa.
After confirming that the dPo1nt (-BOT mark) has been detected, an instruction to run the tape in the forward direction is given and the next process is performed. (1) A high current write instruction is given to the magnetic tape device 18 via the circuit 2.5, and the low frequency generation circuit 2a in the write control circuit 2 is activated to write a specified length of data over all tracks. Write skip identification data SKP using low frequency.

In this way, the recording density indicator ■D is written to only one track, whereas the data S is written from two or more tracks.
Since KP is detected, ID and SKP can be easily distinguished. Note that in IF) detection, the ID is read from one track,
Since this is performed by not reading anything from the remaining tracks, SKP detection is possible when signals are detected from the remaining tracks as well. Furthermore, since data SKP has a low frequency, there are many 0 components, and read signals are likely to be generated.Since all tracks are written, it can be expected that even if the tape is damaged, it can be sufficiently detected. (2) After that, write an IBG of a certain length. This is the skip identification data (
Block) Necessary to distinguish between SKP, record indicator ID, and ARA. (3) After that, a normal record marker ID,
Performs ARA write processing. If this writing is abnormal, the above operation is repeated, but each time the skip identification block S
Extend the KP length. However, if an error occurs even after trying the specified number of times, an abnormal termination report will be reported. Note that during reading, the skip identification block is skipped and the subsequent recording marker recognition process is performed.

In FIG. 1, 3 is a time sense circuit, 4 is a reading control circuit, 6 is a reading circuit, and 7 is the number of stitches of the speed pulse.

A control section 1 takes charge of overall control, and under this control, circuits 2 and 5 perform writing, and circuits 4 and 6 perform reading.

Effects of the Invention As described above, according to the present invention, since the rewriting of the recording mark on the magnetic tape is performed with a shift from the BOT, there is an advantage that the success rate of rewriting is increased.

[Brief explanation of the drawing]

FIG. 1 is a block diagram showing an embodiment of the present invention, FIG. 2 is an explanatory diagram of the operation of rewriting the record mark, and FIG. 3 is a flowchart showing the processing. In the figure, 1 is a magnetic tape control unit, 18 is a magnetic tape device,
MT is a magnetic tape, ID, ARA is a recording indicator, and SKP is skip identification data. Applicant Fujitsu Limited Representative Patent Attorney Minoru Aoyagi

Claims (1)

[Claims] In a system that includes a magnetic tape control device and a magnetic tape device, in a system that rewrites a recording marker onto a magnetic tape medium, when writing a recording marker on the magnetic tape fails, rewinding is automatically performed and the writing is completed. A recording marker rewriting method characterized in that predetermined skip identification data is written over an area beyond the failed area, and the recording marker is written again two times after creating an IBG of a certain length.