JPS5817554A - Control system for writing of magnetic tape device - Google Patents

Abstract

PURPOSE:To prevent precedent data blocks from being erased even in case of a slide of a tape by flowing a write current after detecting a precedent data block ending, and writing data after running the tape by a certain length. CONSTITUTION:When a tape 2 stops, a writing head 7 is returned to a last data block 10. While the tape 2 is not driven, a reading head 8 is at the last data block 10. The tape is started to read the last data block 10 and after the ending of data is detected, a write current is flowed and the tape 2 is run by certain length, thereby writing data. Thus, the last block 10 is never erased. Further, gaps IBG written on the tape have a specified length and the influence of a slip of the tape 2 during starting and acceleration is eliminated.

Description

DETAILED DESCRIPTION OF THE INVENTION This invention relates to a write control method for a magnetic tape device equipped with a streamer function, in particular a gear lag (IBG) between data blocks written on a magnetic tape (hereinafter referred to as tape). This is related to the writing fist control method such as O-long IK.

In general, a magnetic tape device uses a capstan of 30 mm to store a tape 2 wound on a twill reel 1 as shown in Fig. 1.
The data is sent to the machine side reel 4K* and is sequentially written or read. Also, by reversing the capstan 3, the tape 3 is rewound. Since the inertia of the tape 2 winding and rewinding reels is large, the capsta y3 cannot be started and stopped rapidly, so the tape 30Ay fur mechanism absorbs the deviation of the drive tape amount O in the vacuum = Zum 5. ing. 6 indicates the tape roll amount detector, 7 indicates the write head, 8 indicates the read head, and 3 indicates the erase head.Recently, as the amount of information processed by computers has increased, the lids have become larger. However, even with the magnetic tape device mentioned above, it was necessary to increase the speed, so it was possible to improve the performance without increasing the conventional 0111tK depth.Specifically, the tape speed The new so-called service increases the throughput of the conventional process without starting/stopping as much as possible. - The magnetic tape device performs writing and reading while the tape 2 is running at a constant speed, so as shown in Figure 3 N) A blank space called ``O'' is provided, and O acceleration and deceleration are performed to start and stop the tape 2 at this O checkpoint. When the tape snow stops, the write head is located at the center of the IBGO, and when writing to the 0th *a, the tape slack after startup is one running distance jl! *After that, start writing (the write current is already at Kll). When this device is equipped with a striker function and the tape speed is increased, the rolling of the tape and the stop time may be affected by the responsiveness of the reel) compared to the conventional device. With the write V door positioned above the previous data block 10, the write current must be controlled to flow as soon as the write head γ is in the IBG. When the write voltage Il is applied at a certain distance after the start of step 2, if the data yll is slipping, the previous databm
yri1・The meeting was canceled t-) 9 or 111G is the value written in 1 t The first class O problem that cannot be played is **** The main issue * oii is starting the tape, accelerating Knv & ? The present invention provides a write control method for a magnetic tape device that eliminates the above-mentioned problems even if there is a large amount of data.

The feature of the present invention is that the previous data block written on the tape is read by the read head, and after detecting that the data is at risk of fkg, a write current is applied to the write head, and the tape is further run for a certain distance. After that, write the data
Well, the above objectives have been achieved.

The present invention will be explained below with reference to Examples.

FIG. 3 is a conceptual diagram for explaining a fresh example of the write control method of the magnetic tape device according to the present invention. Return it to the 10th position. Read head $ goes to write vYY 1/Tom I
Since the BG is set apart from the BG, when tape 2 is stopped, it is at the 1/0 position. tape 2
Accelerates startup, writes data to tape 2, reads previous data l-tsk1, reads data in td8, detects that data is no longer present, and then applies write current. In the present invention, data is written after the tape 2 has been run a certain distance.

After doing the above, after starting the tape 2, the V
After reading the previous data booter 10 in step 8 and confirming that there is no data, a write current flows to the write head, so there is no need to erase the previous data booter 11g1. 0 More tape! Since the data is written after running the tape for a certain distance, the IBG is set to a certain length.Therefore, there is no effect of slippage caused by starting the tape SO and accelerating K.The 411th is different from the present invention. This is a conceptual diagram for explaining the embodiment.

- When the read command finishes reading the data boot book 1, it goes to the write address.
0 yo l 1/l I B Even if G advances, the process for i is exactly the same as in the case of the third WJ described above. If you want to write additional data after reading the original data, $p,
When writing the additional data, since the old i data may have been written in the boot block, an erase head 9 is provided in front of the write head 7 to erase it. Therefore, the write head 7 is shifted bK so that the erase head 9 is located at the center of the IBG. By doing this, it is possible to write additional data after reading the data pipe while ensuring that the old data has been erased.

When starting and accelerating tape 2, even if tape 2 is overloaded, it is read as in the present invention after confirming that the previous data 1G is gone. Hitoshi and Sana erase the previous data block by applying a write current. Furthermore, after running tape 2 for a certain distance, data is written, so IBGO length -ah
It can be kept constant. Therefore, it is impossible to erase the data uploads during the IBG tape as short as before.

The present invention has been described above with reference to the embodiments, but according to the zero stomach, it is possible to write on the tape t#L round datab a + ivy meeting reading IIR
After reading with the tape head and detecting that there is no data, a write current is applied, and after running the tape for a certain distance, data is written. Even if a tape slip occurs! The effect of providing a write control method that does not erase the entire IBG tape or previous data block is enormous.

[Brief explanation of the drawing]

Figure 1 is the ninth cross-sectional diagram for explaining a magnetic tape device, Figures (a) and (b) are conceptual diagrams for explaining write control of a conventional magnetic tape device, and No. 3-4110 is a diagram according to the present invention. FIG. 3 is a conceptual diagram for explaining each embodiment of a write control method for a magnetic tape device. In agony, 2 indicates the magnetic tape, M indicates the write head, @company read head, 9-line erase head, and 10 indicates the data block. 1st flash

Claims (1)

[Claims] In a data write control method on a magnetic tape of a magnetic tape device equipped with a read function, the four data blocks written on the magnetic tape are written on the magnetic tape. 11L Shihe V
The INK that was read by the host and detected that there was no data
A write control system for a magnetic tape device characterized by supplying a write current to a write head, moving a magnetic tape a certain distance, and writing data.