JPH0215404A - Recording error retrying method for recording device - Google Patents

Abstract

PURPOSE:To effectively use a recording medium by error-retrying in units of block. CONSTITUTION:Data blocks 2, 3,... are recorded in units of the block on a recording medium 1. When the recorded data are checked, and they are detected to be recording errors, the same data are recoded on the position where the block has been recorded, the recording error retrying is executed without shifting the recording block, and the recording medium can be effectively used.

Description

[Detailed Description of the Invention] [Summary] Regarding an error retry method for a recording device, for the purpose of effectively using a recording medium, in a recording device that records data on a recording medium in blocks, When a recording error is detected as a result of recording data and inspecting the recorded data, the same data is recorded again at the recording position of the recording medium where the block where the error occurred was recorded. .

[Field of application of the invention]

The present invention relates to a recording device such as a magnetic tape device, and more particularly to a recording error retry method in a recording device that records data in blocks on a recording medium.

Especially in recording devices that use tape-shaped recording media,
It is configured to record data in blocks called data blocks.

This block is configured with a non-recording area called IBC sandwiched therebetween.

In such a recording device, data is recorded on a recording medium in blocks, and then the recorded data in blocks is reproduced to check whether the data is recorded normally.
A so-called read-after-write check is performed.

If data is not recorded normally, the data is re-recorded in some way through error retry processing.

For such error glue trial processing, a method is desired that is high-speed and allows effective use of the recording medium.

[Conventional technology]

A conventional recording error retry processing method for such a recording apparatus will be explained using FIG. 7.

That is, in the example shown in FIG. 7, a case will be explained in which a magnetic tape device is used as the recording device.

Conventionally, as described in FIG. 7(1), data is recorded on a recording medium 1 in units of two blocks called data blocks. First, a data block is recorded by a recording head.

At the same time, the data of the recorded block 2 is reproduced by a reproducing head provided behind the recording head to check whether it has been recorded normally.

If a recording error is determined as a result, the recording medium is backspaced (traversed in the opposite direction), the recording head is repositioned to the beginning of the block where the error occurred, and then the block where the error occurred is erased.

Then, as shown in FIG. 7(2), the recording medium 1
The same data was recorded at the rear position.

[Problem to be solved by the invention]

In this way, in the recording error retry method for conventional recording devices, if data recorded in blocks at a certain position on a recording medium is determined to be an error by inspection, the recording position on the recording medium is shifted. A method of recording was adopted.

It is true that this method is the method that enables the quickest recovery from recording errors when a recording error occurs due to a defect on the recording medium, but when the cause of recording errors is analyzed, recording errors It has been found that recording errors, which occur when accurate recording is not possible due to dust adhering to the medium, account for a large portion of these errors.

It has also been found that most of the dust adhering to the medium can be removed by moving the recording/reproducing head back and forth several times while bringing it into contact with the recording medium l.

Therefore, if a recording error retry method is adopted as in the past, even though it would normally be possible to recover from the error by re-recording at the position on the recording medium where the recording error occurred, each time a recording error occurs, the recording position There is a problem in that the recording medium cannot be used effectively because of the change in the recording medium.

An object of the present invention is to provide a recording error retry method that can effectively utilize a recording medium.

[Means to solve the problem]

In order to achieve the above object, the recording error retry method of the recording apparatus of the present invention is implemented in a block unit called data block 2 on the recording medium 1, as shown in the diagram explaining the principle of the present invention in FIG. In a recording device that records data, when data is recorded in units of two blocks and a recording error is detected as a result of inspecting the recorded data, the record in which the block in which the error occurred is recorded. The same data is recorded again at the recording position on the medium.

That is, in the present invention, the tape-shaped recording medium 1 is used as a recording medium.
This is a device that records data in units of two data blocks using
At the same time, the data is inspected by reading the data of the recorded block by a playback head (not shown) disposed behind the recording head with respect to the running direction of the tape-shaped recording medium, and as a result, If an error is detected in the recorded data, backspace the tape-shaped medium (Fig. 1 ■) to position the recording head at the beginning of the block where the error was detected, and then move the tape-shaped medium forward. Then, the same data is recorded again at the recording position of the recording medium where the block in which the error occurred was recorded ((2) in FIG. 1).

Furthermore, in the present invention, data is recorded on the tape-shaped recording medium 1 in units of two blocks by a recording head, and a reproducing head disposed behind the recording head with respect to the running direction of the tape-shaped recording medium 1. The first step is to check the data by reading the data of the recorded block (Fig. 1 ■). As a result, if an error is detected in the recorded data,
A second step of backspaces the tape-shaped medium 1 and positions the recording head at the beginning of the block where the error has been detected (Fig. 1), and then runs the tape-shaped medium 1 in the forward direction to A third step of recording the same data again at the recording position of the recording medium where the block in which the error occurred was recorded (Fig.
Repeat steps 3 to 3, and if the error is not recovered, remove the tape-shaped recording medium 1.
The fourth step is to erase the block in which the error occurred (■, ■ in Figure 1), and the fifth step is to re-record the same data as the data recorded in the previous block at the recording position of the next tape-shaped recording medium. It consists of steps (■ in Figure 1).

[For production]

As shown in FIG. 2, the recording error processing flow of the present invention,
In the present invention, when a write error is detected in (a), within the range of a predetermined number of retry attempts, as explained in FIG. d) Backspace again and re-record.

If the error is not recovered even after rewriting at the same position a predetermined number of times according to (C), as shown in FIG. 1, recording at the same recording position is given up. The recording position of the error block is erased, and the same data is recorded at the recording position of the next new recording medium.

If the error is not recovered even at this new recording position, re-recording is performed multiple times.

If the error still does not recover, the same data is recorded again in another new position.

If the error is not recovered even after the movement to the new position is repeated a plurality of times as shown in (b), an error report is made as shown in (f) and the process ends.

In this way, in the present invention, since re-recording is performed at the same position on the recording medium, recording errors are often caused by dust adhering to the recording medium.
Errors are often recovered by re-recording multiple times (as a result, the recording medium can be used more effectively).

Furthermore, by providing a means for counting the number of times of erasure, it is possible to accurately identify defective locations on the recording medium.

〔Example〕

FIG. 3 is a system configuration diagram of an embodiment of the present invention.

In the figure, numeral 10 is an input/output control device such as a magnetic tape control device, which receives recording/playback commands from a higher-level device such as a channel device, and thereby input/outputs the magnetic tape devices etc. connected under it. It drives and controls the device 11.

Reference numeral 11 denotes an input/output control device such as a magnetic tape device, which drives a recording medium in response to drive commands from the input/output control device 10 and performs recording and reproduction on the recording medium.

The embodiment shown in FIG. 3 will be explained by taking the magnetic tape control device and the magnetic tape device as examples, respectively, as described above.

The magnetic tape control device 10 operates under microprogram control and mainly has a configuration as shown in the figure.

That is, a higher-level interface control section 12 for exchanging signals with the higher-level device, a lower-level interface control section 13 for controlling the lower-level magnetic tape device 11, and a microprocessor MPU for controlling the overall operation.
14, a ROM 15 that stores programs etc. for the operation of the microprocessor 14, a RAM 16 that temporarily stores counters and various control information during actual operations, and a data buffer that temporarily stores recording and reproduction data. 17, the format for actually recording the data to be recorded on the recording medium, such as editing the data into the actual recording format, such as adding a specific code to the beginning and end of the data, It also includes a format control section 18 that checks the format of the reproduced data and extracts only the data, and a modulation/demodulation circuit 19 that modulates the data to be recorded and demodulates the reproduced data.

In the present invention, a retry counter 20 and a retry position change counter 21 are provided on the RAM 16.

Although not shown in detail, the magnetic tape device 11 includes: a drive control circuit 22 that controls the drive of the magnetic tape under control from the magnetic tape control device 10; and a pair of reels 24 for driving the magnetic tape 23. .2
5, and a head 26 for recording and reproducing data on the magnetic tape 23.

The operation according to the present invention in FIG. 3 will be explained using FIGS. 4 to 6.

FIG. 4 is a diagram illustrating an error retry processing method according to an embodiment of the present invention, and particularly explains the magnetic tape drive operation. This operation is explained in Figures 5 and 6.
This will be explained by quoting it in the explanation of the figure.

FIG. 5 is a data write processing flow according to an embodiment of the present invention.

The MPU 14 receives instructions from the host device in step 1.
Always monitor at 00.

When a command is received, it is determined in step 101 whether the command is a write command or another command.

If the command is not a write-related command, the process advances to step 102 and other processing is executed. Regarding this process,
Since it is not directly related to the present invention, it will not be described in detail here.

Next, if it is a write-related command, the process advances to step 103, where data to be written is received from the host device and is temporarily stored in the data buffer circuit 17.

Upon receiving the write command, the microprocessor 14 issues a tape drive command to the magnetic tape device 11.

In the magnetic tape device 11, when a drive command is issued in the drive control circuit 22 and the nth block in FIG. 4 is to be recorded from now on, even if the magnetic tape is started from a stopped state, For example, start up as shown in (■) in Fig. 4.

Furthermore, if the program is being recorded continuously, it enters the area of block n while maintaining a predetermined speed.

When the magnetic tape controller enters the predetermined constant speed shown in FIG. The signal is sent to circuit 19.

The data modulated by the modulation/demodulation circuit 19 is sent to the magnetic head 26 and recorded on the magnetic tape 26 in step 105.

At the same time, in step 106, the magnetic head 26
The currently recorded data of the n-th block of the fourth part is reproduced from the reproduction head.

This reproduced data is passed through the modulation/demodulation circuit 19 to the format control section, and is inspected to see if it has been recorded normally.

This inspection is performed, for example, by checking a check code to which format check data is added.

As a result, if the recording is normal in step 107, the MPU 14 reports the normal end to the host device, and the processing for one write command ends.

Note that there are cases where data is continuously recorded over a plurality of blocks, such as in a streaming magnetic tape device.

Further, in step 107, if the flock cannot be recorded normally and an error is detected, the process proceeds to the error retry process shown in FIG.

FIG. 6 shows an error retry processing flow according to an embodiment of the present invention.

In step 109, the value of the retry counter 20 provided on the RAM 16 is incremented by one.

Furthermore, although not shown, when an error is detected, the drive of the magnetic tape is stopped, and a stopping operation is started as shown in (■) in FIG.

Then, in step 110, it is determined whether the contents of the retry counter 20 have been determined in advance or have reached the allowable number of tries.

In this embodiment, the number of retries is set to four, but it is not limited to this.

Then, the MPU 14 issues a backspace command to the magnetic tape device 11, and drives the magnetic tape as shown in FIG.

Note that in order to position the head at the beginning of block n to be rerecorded, it is necessary to detect the beginning position of the block in some way, but in this embodiment, step 11
As shown in 2, when backspace is executed, the state of the recording medium is back-read by the reproducing head at the same time, and the rBG pattern is detected.

Then, in step 113, the running shown in FIG. In step 114, the tape drive is stopped as shown in FIG.

Then, in step 115, a command to drive the tape in the forward direction is issued to start driving the tape as shown in FIG. The stored data to be recorded is recorded on the recording medium again.

Then, a light after light check is performed in the same manner as described in step 106.

If the write has been performed normally in step 118, a normal end direction is sent to the host device, and the processing for the write command is ended.

If you are unable to write correctly again, please write the fourth
The tape is stopped as shown in (■) in the figure, and the retry operation is performed again from step 109.

Then, in step 110, the error retry for the n-th block data is performed four times to the position shown by the solid line in FIG. 4, and if the error is still not recovered, the process proceeds to step 120.

In step 120, first, the retry counter 20
Reset the value of

Then, in step 121, the value of the retry position change counter 21 is incremented by one.

In step 122, if it is detected that the value of the retry position change counter 21 has changed the recording position a predetermined number of times, in step 129, an abnormal termination report is sent to the host device, and the process is terminated. do.

In step 122, retry position change counter 2
If 1 is less than the predetermined number of times, the process advances to step 123.

Then, the MPU 14 issues a backspace command to the magnetic tape device 11 to backspace the magnetic tape as shown in FIG.

Then, in steps 124 and 125, the IBG is detected in the same manner as described in steps 112 and 113, and the tape is stopped in step 126 as shown in (■) in FIG. 4.

Thereafter, the MPU 14 issues a tape drive command again to drive the tape in the forward direction, and in step 128, data in the n-th block indicated by the solid line in FIG. 4 is erased.

Then, the process proceeds to step 116.

After the erasure of data in step 128 is completed, the magnetic tape 23 runs at a constant speed from ■ to ■ without stopping, as shown in FIG.

Then, in step 116, the same data as the data to be recorded in the n-th block is recorded at the position indicated by the broken line next to the solid line shown in FIG.

If an error occurs in the recording at this step,
An error pasting trial is performed by driving the tape as indicated by ■ to @ shown in FIG.

If the error is not recovered at this recording position, the recording position is changed and the same data is recorded again until the value of the position change counter in step 122 is exceeded.

Therefore, next, an error retry is performed by driving the tape from @ to [phase] in FIG.

In this embodiment, 4 attempts at the same recording position on the magnetic tape are allowed, and 4 attempts at changing the position are allowed, so 16 attempts are made in total. There is.

If the error is not recovered even after this retry, an abnormality report is reported and the termination is notified.

[Effects] As described above, in the present invention, since the error retry is performed at the same recording position on the recording medium in the error retry, the recording medium can be used effectively.

[Brief explanation of the drawing]

Figure 1 is a diagram explaining the principle of the present invention, Figure 2 is a diagram explaining the write error processing flow, Figure 3 is a system configuration diagram of an embodiment of the present invention, and Figure 4 is an error retry diagram of an embodiment of the present invention. FIG. 5 is a data write processing flow according to an embodiment of the present invention. FIG. 6 is an error retry processing flow according to an embodiment of the present invention. FIG. 7 is a diagram explaining a prior art related to the present invention. Each is shown below. Furthermore, in the figure, 1 is a recording medium (magnetic tape), 2 is a data block (block), 14 is a microprocessor (MPU), 17 is a data buffer circuit, 18 is a format control circuit, 19 is a modulation/demodulation circuit, and 20 is a retry counter. , 21 is a retry position change counter, and 26 is a magnetic head.

Claims (3)

[Claims] (1) In a recording device that records data in units of blocks (2) on a recording medium (1), data is recorded in units of blocks (2), and as a result of inspecting the recorded data, it is determined that there is a recording error. A recording error retry method for a recording apparatus, characterized in that, when detected, the same data is recorded again at a recording position of a recording medium where the block in which the error occurred was recorded. (2) In a recording device that records data in blocks (2) on a tape-shaped recording medium (1), data is recorded in blocks on the tape-shaped recording medium by a recording head, and The data is inspected by reading the data of the recorded block by a playback head placed at the rear in the running direction of the tape-shaped recording medium, and as a result, if an error is detected in the recorded data,
Backspace the tape-shaped medium to position the recording head at the beginning of the block in which the error has occurred, and then run the tape-shaped medium in a forward direction to record the block in which the error has occurred. A recording error retry method for a recording device, characterized in that the same data is recorded again at a recording position on a medium. (3) In a recording device that records data in blocks on a tape-shaped recording medium, the data is recorded in blocks on the tape-shaped recording medium by a recording head, and the recording head runs the tape-shaped recording medium. A first step of inspecting the data by reading the data of the recorded block by a playback head disposed backward in the direction, and as a result, if an error is detected in the recorded data,
A second step of backspaces the tape-like medium and positions the recording head at the beginning of the block where the error has been detected.
Thereafter, a third step of running the tape-shaped medium in a forward direction and recording the same data again at the recording position of the recording medium where the block where the error occurred was recorded, and if the block was recorded normally. The first to third steps are repeated a predetermined number of times until the error occurs, and if the error is not recovered, the fourth step is to backspace and erase the block recording position where the error occurred on the tape-shaped recording medium. and a fifth step of re-recording the same data as the data recorded in the block at the recording position of the next tape-shaped recording medium.