JPH09185805A - Tape check method for data recording device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a tape check method and a device therefor capable of automatically and surely discriminating a new tape from an initialized one and speeding up an operation by minimizing a tape operation. SOLUTION: In a data recording and reproducing device, it is performed to judge whether or not a tape is already initialized. A tape length equivalent to 5600ID is transferred from the tape top (step 2) by using IDC (indirect address information) obtained from a rotation angle of a reel. This is a position where header information is surely recorded when the tape is already initialized (recorded). At step 4, the ID is read out of the tape and it is checked with the tape whether or not a reading of the ID varies, and if the reading will not change within a prescribed time, the tape is decided to be a new one, while it is an initialized one if it changes.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a tape recording method in a data recording apparatus for recording a large amount of data sequentially, for example, a data recording apparatus in which data is recorded on a magnetic tape by a helical scan head. .

[0002]

2. Description of the Related Art With the increase in data capacity, the need for a data recording device for recording data on a magnetic tape is increasing as a means for storing a large amount of data. In the magnetic tape, tracks in the longitudinal direction are formed above and below in the width direction of the tape, and helical tracks are formed between them. A helical track is formed by a magnetic head mounted on the rotating drum.

Of the upper and lower longitudinal tracks, the upper track is a control track, on which control pulses are recorded. The lower track is a time code track and the time code is recorded. This time code indicates the position of the tape in the longitudinal direction and is the physical ID of the tape. This ID is SMPT
The E time code expresses the digits of hours, minutes, seconds, and frames, and also enables expression in units smaller than frames (added for each track set). Therefore, by reading the ID in the form of the time code, the position of the head on the tape can be known.

Further, since the capacity of one magnetic tape is large (for example, 42 GB), one tape is used by being divided into a plurality of areas. This area is called a partition or volume. Header information for managing a set of one or more partitions recorded on the entire tape is recorded at the beginning of the recording area of the tape. Header information for partition management is written at the beginning of each partition. By setting partitions in this way, one tape can be used as if it were a plurality of tapes. The DTF format has been proposed as one of the formats related to the addition of IDs and the configuration of partitions as described above. Not limited to this format, a storage device using a magnetic tape usually defines a tape format.

Digital data can be recorded and reproduced on the magnetic tape to which the ID as described above is added. Therefore, it is necessary to perform a process (initialization process) of adding an ID to the magnetic tape for the new tape. In other words, normal tape operation is treated as if initialization is complete. If the new tape is incorrectly used for normal operation, the tape position cannot be found because the ID value required for moving the tape position is not recorded. An error countermeasure, which is different from the necessary countermeasure, such as tape initialization, is taken, resulting in wasted time and labor. On the other hand, if initialization is completed and a tape that has already been recorded is mistaken for a new tape and initialized, a irreversible situation of erasing recorded data occurs.

[0006]

Because of such a problem, there is a need for means for automatically discriminating between a new tape and an initialized tape without human intervention. Some conventional magnetic tape devices automatically check a new tape, which is called auto-formatting,
In the case of a new tape, some devices have a function of initializing. However, even in a device having this kind of new tape check means, the method is to play the tape from the tape top and judge that it is a new tape if no data is written until a timeout occurs for a few seconds. Met.

The conventional method requires reproduction for several tens of seconds in order to avoid the risk of erroneously discriminating a tape on which data is recorded far away from the tape top as a new tape. It required a lot of time unrelated to the recording / reproducing operation, and was inefficient.

Therefore, an object of the present invention is to provide a tape check method in a data recording apparatus which can automatically judge whether or not it is a new tape and minimize the operation of moving the tape position necessary for the judgment. It is in.

[0009]

In order to achieve the above object, the present invention relates to a data recording apparatus which records address information indicating a tape position on a track in the longitudinal direction of the tape when the tape is initialized. , A method of checking whether the injected tape has already been initialized, and in the case of initialized or recorded tape, the data is always recorded using indirect address information. The tape is fed to the predetermined position, the reproduction is performed from the predetermined position, the address information is read, and the initialized or recorded tape is determined based on the read address information. And a tape check method in a data recording device.

In the case of an initialized or recorded tape, header information for managing the entire tape is recorded at a predetermined position. Therefore, it is possible to automatically determine whether the tape has been initialized or recorded by feeding the tape to this predetermined position, starting the reproducing operation, reading the address information, and checking whether the address information changes. Since the header information is loaded into the memory in the device at the time of tape injection, it is possible to determine whether it is the initial tape or not by utilizing the tape feeding operation for this loading. Therefore, the tape feeding operation only for the purpose of discrimination can be minimized and a high speed operation can be achieved.

[0011]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings. FIG. 1 is a block diagram showing the overall configuration of an embodiment of a data recording / reproducing apparatus according to the present invention. In FIG. 1, reference numeral 1 denotes a host computer interface unit, and this interface unit 1
Connects a host computer (not shown) and a data recorder as the recording / reproducing unit 10 with, for example, a SCSI interface. The SCSI interface is a SCSI (Small Computer System Interface: ANSI).
X3.131-1986) Standard interface.

Host computer interface section 1
Is an interface device equipped with a tape stream emulation that controls a data recorder like a tape streamer. The interface unit 1 has a formatter function of creating a specific format on a tape and exchanging data on it. That is, data is, for example, 1 ID of the tape
Blocking of data to be grouped (for example, 1 ID = 4 tracks), data to be grouped at a delimiter of a file (also called a partition, volume, etc.) instructed by the host computer, and a sub used for cueing at the time of playback. Perform formatting process to add code. The ID in this embodiment is one of the address information.

At the time of data recording, the data collected by the host computer interface unit 1 for each ID is added with an error correction code by the signal processing circuit 2 and modulated so that it can be recorded on a tape. Then, it is equalized by the RF circuit 3. A predetermined tension is applied to the tape 7 wound around the reels 8 and 9, and the recording / reproducing head 6 provided on the drum is rotated to stand by.
After being turned on, data is recorded by the recording / reproducing head 6 while the tape is running under the control of the servo circuit 5.

When reproducing data, the recording / reproducing head 6 reproduces the data while applying a predetermined tension to the tape 7 wound around the reels 8 and 9 and rotating the drum. The reproduction signal from the tape 7 is equalized by the RF circuit 3, and then subjected to error correction processing and the like by the signal processing circuit 2 and processed by the host computer interface section 1 such as recognition of file breaks. The data obtained by such processing is output according to the file number and the requested data size from the host computer.

The system control circuit 4 cues the tape 7 and controls recording / reproduction in response to a request from the host computer interface section 1. The servo circuit 5 controls the positioning of the tape 7 so that the data can be correctly recorded and reproduced. A recording / reproducing unit 10 includes the signal processing circuit 2, the RF circuit 3, the system control circuit 4, the servo circuit 5, the recording / reproducing head 6, the tape 7, and the reels 8 and 9.

FIG. 2 shows an example of the configuration of the host computer interface section 1. The SCSI interface unit 11 separates the data from the host computer into commands and data, and sends the commands to the main CPU 12
And write the data to the buffer memory 13. The buffer memory 13 has a capacity of 32 Mbytes, for example. Data is once stored in the buffer memory 13 and then sent to the processor (signal processing unit 2) via the processor interface unit 14. The command is sent from the main CPU 12 via the dual port RAM 15.
The data is sent to the sub CPU 16, the sub CPU 16 is coupled to the system controller 4 of the recording / reproducing unit 10 via the serial interface 21, and the sub CPU 16 controls the recording / reproducing unit 10.

RAM 1 for the bus of the main CPU 12
7 and ROM 18 are connected. RAM17 is CP
It functions as a work RAM for U12 and also temporarily stores header information. Since the header information (partition set management information recorded for each tape, partition management information recorded for each partition) is rewritten each time during recording / reproduction of the tape, the access speed becomes slower. Rewriting of the RAM 17 is limited by the control of 16 and 16. That is, the header information (specifically, partition set management information) recorded at a predetermined position on the tape when the initialized tape (including the recorded tape; the same applies below) is first injected. ) Is read, the read header information is loaded into the RAM 17, and when the tape is ejected, the header information in the RAM 17 is recorded on the tape. As will be described later, this embodiment checks whether or not the tape is a new tape in association with the header information loading operation at the time of tape injection.

RAM for the bus of the sub CPU 16
19 and the ROM 20 are connected. Dual port R
The AM 15 is provided to perform communication between the two CPUs 12 and 16. Further, the reproduction data reproduced from the tape and processed by the signal processing unit 2 is stored in the buffer memory 13 via the processor 14. The reproduction data stored in the buffer memory 13 is transferred to the host computer via the SCSI interface unit 11.

The above-mentioned data recorder, in particular, the operation for determining whether the injected tape is a new tape or an initialized tape will be described. FIG. 3 is a flowchart showing this operation. This operation is performed by the main CPU 12 and the sub CPU 16 described above.
The tape feeding operation is controlled by the sub CPU 16.

When the tape is injected into the apparatus, the tape is rewound to the tape top (step 1). Next, by IDC search, the tape is fed from the tape top in the recording direction, for example, 5600 ID. I
The DC search is a method of indirectly obtaining the physical ID (address information) of the tape and searching for the target position based on it. The IDC is a relative tape length in units of ID calculated by the servo circuit 5 in FIG. 1 from the length of the outermost diameter of the tape and the rotation angle of the reel. IDC
1 unit of is almost equal to 1 ID recorded on the tape. When the IDC is used, even with respect to the tape portion where the ID is not recorded, it is possible to locate the tape in units of the ID with accuracy. To obtain the IDC, various methods can be adopted without being limited to the rotation angle of the reel.

When the IDC search is completed, the ID reader value is read from the longitudinal track of the tape and the read value (idr value) is the IDR sense. Then, after the timer value is set to 0, the reproduction is started.

Step 4 is the step 4 of starting reproduction.
a, step 4b to determine if the read ID reader value changes from the IDR, and step 4c to detect a 5 second timeout by a timer.

When the ID reader value changes, in step 5, the tape is stopped, it is determined that the tape has been initialized, the new tape flag is reset, and the determination result is reported to the host computer. On the other hand, the ID reader value is 5
In the case of a timeout that does not change for a second, the tape is stopped, a new tape is determined, a new tape flag is set, and the determination result is reported to the host computer. By performing such a tape check prior to the operation of moving the tape position, it is possible to quickly shift to the next operation. The next operation is the tape initialization operation for new tapes and the initialized tape operation for initialized tapes.
This is an operation related to recording / reproduction.

The above-described embodiment of the present invention will be described more specifically with reference to FIGS. 4 and 5. FIG.
Shows a procedure for performing a new tape check on an initialized tape. In the first step 1, the tape 7 is rewound and positioned on the tape top.

The next step 2, which is a search by the IDC, fast-forwards the tape in the recording direction from the tape top in an amount corresponding to, for example, 5600 ID. When the use of the tape is started, the position of 5600 ID from the top of the tape always has predetermined data (for example, volume set information table VS for file management) in the tape format.
This is the position where IT) is recorded. In step 3, the ID reader value at this position is read and the ID count value =
Remember the position of 5600 as the ID reader value "0" ID. Then, the reproduction is started.

In step 4, while playing the tape,
Read the ID reader value and check if the ID reader value changes from '0' ID. For initialized tapes,
Since the ID is recorded, the ID reader value is immediately "0".
It will be a larger value. In step 5, the tape is stopped (stop operation). The discrimination result obtained by the above processing means that the ID reader value is changed, and therefore it is not a "new tape". Therefore, the new tape flag is reset and the discrimination result is reported to the host computer.

Next, with reference to FIG. 5, a case of checking a new tape will be described. In the first step 1 ', the tape 7 is rewound and positioned on the tape top. The next step 2'is the IDC search,
Fast forward in the recording direction by an amount equivalent to 5600 ID from the tape top. As mentioned above, 56 from the tape top
The position of 00ID is when you start using the tape.
This is the position that is always recorded on the tape format.

In step 3 ', the ID reader value at this position is read, but since it is a new tape, the initial ID reader value (`0' when the tape is injected).
I will remember the ID). Then, the reproduction is started. In step 4 ', the ID reader value is read while reproducing, and it is checked whether the ID reader value changes from "0" ID. Since the ID is not recorded on the new tape, the ID reader value does not change from "0" and the reproduction continues for 5 seconds until the time-out occurs.

In step 5 ', a time-out occurs as a result of the unchanged ID reader value and the tape is stopped. The determination result obtained by the above processing means "new tape" because the ID reader value does not change.
Therefore, a new tape flag is set and the discrimination result is reported to the host computer.

The present invention is not limited to the above-described embodiment, and various modifications can be made. For example, this invention
D for tape drives that support variable transfer rates
It can be applied when supporting a file format such as the TF tape format.
Also, an example has been shown in which the system control circuit 4 inside the recording / reproducing unit 10 as a data recording / reproducing device moves the tape 7 by the reels 8 and 9 via the servo circuit 5, but the host computer side via the interface. ,
Alternatively, the recording / reproducing unit may be controlled from another device that performs the same operation, for example, a dedicated experimental data collecting device.

[0031]

According to the present invention, the judgment as to whether or not the tape can be initialized is made by checking the recorded contents of the tape without relying only on the human being, so that a reliable judgment can be made. , Reduce the probability of error, and also automatically make the distinction,
It is no longer necessary for people to be involved in
Labor can be saved. The present invention is particularly effective when the data size of one roll of cartridge tape is large and the recording density is high, in other words, when the influence of a misjudgment as to whether or not the tape can be recorded is large. is there.

In the present invention, since the value of the ID reader is used to judge whether the tape is a new tape, it is not necessary to read the helical data, and the judgment can be made if only the longitudinal recording can be read.

According to the present invention, in order to check a new tape, a search from the tape top is performed by searching with an ID counter.
An operation of fast-forwarding in the recording direction by an amount corresponding to 600 ID is required. This action actually makes the tape 5600
It takes time to move the ID. However, it is only performing the first tape operation required to read the header information recorded at this position, and is not performing an unnecessary operation. As described above, according to the present invention, since the tape operation only for the new tape check is minimized, the total time required for recording / reproducing data can be shortened and the tape access can be performed at high speed.

[Brief description of the drawings]

FIG. 1 is a block diagram of the overall configuration of an embodiment of the present invention.

FIG. 2 is a block diagram showing a configuration of a host computer interface section in an embodiment of the present invention.

FIG. 3 is a flowchart for explaining the operation of one embodiment of the present invention.

FIG. 4 is a schematic diagram for explaining the operation in the case of an initialized tape in one embodiment of the present invention.

FIG. 5 is a schematic diagram for explaining the operation in the case of a novel tape in one embodiment of the present invention.

[Explanation of symbols]

 1 host computer interface section 2 signal processing circuit 4 system control circuit 6 recording / reproducing head 7 tape 10 recording / reproducing section

Claims (4)

[Claims] 1. A data recording apparatus, which records address information indicating a tape position on a longitudinal track of the tape when the tape is initialized, and whether or not the injected tape has already been initialized. If the tape has been initialized or recorded, the step of sending the tape to the predetermined position where the data is recorded by using the indirect address information and the reproduction from the predetermined position. And a step of reading the address information, and a step of determining whether the tape is an initialized tape or a recorded tape based on the read address information. 2. The tape check method according to claim 1, wherein the indirect address information is address information calculated from a rotation angle of a reel. 3. The tape check method according to claim 1, wherein the data recorded at a predetermined position is header information, and when the initialized tape is injected, a loading operation for reading the header information is performed. A tape check method characterized by being performed. 4. The tape check method according to claim 1, wherein a new tape flag is provided, and in the case of a new tape, the flag is set, and the tape check method is reported to an upper device.