JPH10177765A - Data recording and reproducing device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To enable data transfer in a signal compression state in a data transfer origin and a data transfer destination by deciding a transferred signal compression/expansion mode in a data transfer origin and a data transfer destination, and processing transferred data with a compression/expansion mode. SOLUTION: A compression/expansion mode of a data compression/expansion circuit of a data recording and reproducing device being a data transfer origin and a data compression/ expansion circuit 204 of the data recording and reproducing device being a data transfer destination is set by a host computer 500 automatically or manually. In the case of an automatic mode, data of the prescribed format of the data recording and reproducing device generated based on data of a SCSI format transferred to SCSII/F215 in a data reproducing device side being a transfer destination of data is supplied to the data compression/expansion circuit 204, a compression/expansion mode at the time of compression and expansion is automatically set conforming to a mode selection command among copy command transferred from the host computer 500.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a data recording / reproducing apparatus having a function of transferring data between a data transfer destination and a data transfer source.

[0002]

2. Description of the Related Art Conventionally, a data recording / reproducing apparatus having a function of transferring data is used, and a data recording / reproducing apparatus of a data transfer source and a data reproducing apparatus of a data transfer destination are connected via a common network to transfer data from a data source to a data transfer destination. When transferring data, the data recorded on the data recording / reproducing apparatus is usually compressed and recorded in order to reduce the recording / reproducing time and the required recording capacity.

Therefore, at the data transfer destination, the recorded data is decompressed and then transferred to the data transfer destination, and the transferred data is compressed and then recorded.

[0004]

In such conventional data transfer, when such data compression / expansion is performed, even if the default value of the compression / expansion mode of the data transfer source is different from the default value of the data transfer destination. There is no problem because the data transferred on the common network is expanded.

However, in consideration of compressing and transferring data to be transferred via a network in order to further reduce the data transfer time, the default value of the transferred compressed data is determined by the compression and decompression of the transfer destination and the transfer source. There has been a problem that the data transfer destination may not be able to accept the data due to a different method.

SUMMARY OF THE INVENTION The present invention has been made in view of the above points, and provides a data transfer function which enables compressed data to be transferred by a data compression / expansion method which can be transferred between a data transfer destination and a data transfer source. And a data recording / reproducing apparatus having the same.

[0007]

In a data recording / reproducing apparatus having a data transfer function, means for determining a signal compression / expansion mode for transferring data between a data transfer source and a data transfer destination;
Means for processing data transferred in the signal compression / decompression mode is provided, and the data transfer destination and the data transfer source can perform data transfer in a signal compressed state.

[0008]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of a data recording / reproducing apparatus according to the present invention will be described below with reference to FIGS.

FIG. 1 shows an example of a basic configuration in a case where data is directly transferred from one data recording / reproducing device to the other data recording / reproducing device using two data recording / reproducing devices. Reproduction devices 1A and 1B
, A common bus 216A, and a host computer 500. The data recording / reproducing devices 1A and 1B are connected to the host computer 500 via the common bus 216A, and the host computer 500, the data recording / reproducing devices 1A and 1B are connected. , The data can be mutually transferred through the common bus 216A.

The copy command and data transfer shown in FIG. 1 will be described later.

The common bus 216A is, for example, a well-known SCSI standard bus line.

Referring to FIG. 2, when data is transferred from one data recording / reproducing device to another using two data recording / reproducing devices, the host computer 5
9 shows another example of the basic configuration in which data is transferred via 00.

The example shown in FIG.
A and 1B, a common bus 216A, and a host computer 500, and the data recording / reproducing apparatuses 1A and 1B
And the host computer 500 via the common bus 216.
The connection configuration is the same as that of the example shown in FIG.

However, in this example, as shown by an arrow X in FIG. 2, data is transferred from the data recording / reproducing apparatus 1A to the host computer 500, and once the data is taken into the host computer 500, the data is indicated by an arrow Y. As described above, the operation of transferring this data from the host computer 500 to the data recording / reproducing apparatus 1B is performed. This operation allows the transfer of this data from the host computer 500 to the data recording / reproducing apparatus 1B. , By the host computer 500
A copy command to be described later can be added.

Next, an example of the configuration and operation of the main part of the data recording / reproducing apparatus shown in FIGS. 1 and 2 will be described with reference to the block diagram shown in FIG.

The data recording / reproducing apparatus A shown in FIG.
The data recording / reproducing apparatus B and the data recording / reproducing apparatus B have the same configuration as each other. Therefore, in FIG. 3, the main part of the data recording / reproducing apparatus A is shown as 1A. The internal configuration is omitted.

Referring to FIG. 3, a data recording / reproducing apparatus 1A comprises:
Magnetic tape recording / reproducing unit 100, main system control circuit 20
1. Data compression / expansion circuit 204, memory control circuit 20
5, the main memory circuit 206, the SCSII / F 215, the encoder 230 and the decoder 240.

A data input / output port (not shown in the drawing) of the main memory circuit 206 is connected to a data input / output port on the memory side of the memory control circuit 205. An input / output port on the data compression / expansion circuit side of the memory control circuit 205 is connected to an input / output port on the memory control circuit side of the data compression / expansion circuit 204.
The F side input / output port is connected to the data compression / expansion circuit side input / output port of the SCS11 / F215, and
The external input / output port of the I / F 215 is a common bus 216
A, so that data can be exchanged between these input / output ports.

The output port on the encoder side of the memory control circuit 205 is connected to the input port of the encoder 230, the input port on the decoder side of the memory control circuit 205 is connected to the output port of the decoder 240, and the signal output side of the encoder 230 is An input / output port connected to a recording signal input side of the magnetic tape recording / reproducing unit 100, and a reproduction data signal output side of the magnetic tape recording / reproducing unit 100 connected to a reproduction data signal input side of the decoder 240 It is configured so that data and signals can be mutually transferred and received between signals and between signal inputs and outputs.

The direction of data transfer between the ports is as follows.
In FIG. 3, each arrow indicates a bidirectional data transfer, and a unidirectional arrow indicates a port connection that transfers data only in the direction of the arrow. The direction of signal transfer between the magnetic tape recording / reproducing unit 100 and the encoder 230 and the decoder 240 is also indicated by the direction of the arrow.

The main system control circuit 201, the data compression / expansion circuit 204, the SCSII / F 215 and the magnetic tape recording / reproducing unit 100 are controlled by the main system control circuit 201 through an internal control bus 219. Are configured to be able to send and receive control signals to and from each other.

Next, in the configuration shown in FIG.
The operation when the data transferred from the 16A to the SCSII / F 215 is recorded by the magnetic tape recording / reproducing unit 100 will be described.

In FIG. 3, SCSII / F215 is
Main system control circuit 210 through internal control bus 219
And the SCSII / F2 from the common bus 216A.
15 is transferred to the SCSI format data.
In the CSII / F 215, the data is converted into data in a predetermined format of the data recording / reproducing device, and the data in the predetermined format of the data recording / reproducing device is converted into data of the SCSII / F21
5 to the data compression / decompression circuit 204.

The data compression / expansion circuit 204 is controlled by the main system control circuit 201 through the internal control bus 219 to convert the data supplied to the data compression / expansion circuit 204 in a predetermined format into the data compression / expansion circuit. The data recording / reproducing apparatus is provided with data expansion / compression in the expansion circuit 204 or through the data compression / expansion circuit 204 and data compression / expansion in the data compression / expansion circuit 204 or through the data compression / expansion circuit 204. Is supplied to the memory control circuit 205.

The memory control circuit 205 is controlled by the main system control circuit 201 through an internal control bus 219 to compress or expand data in the data compression / expansion circuit 204 or to pass the data compression / expansion circuit 204 through. The data recording / reproducing device writes data in a predetermined format from the memory control circuit 205 to the main memory 206.

The memory control circuit 205 is controlled by the main system control circuit 201 through an internal control bus 219, and transfers the data signal of a predetermined format written in the main memory circuit 206 to the data recording / reproducing apparatus on a magnetic tape. The main memory circuit 20 converts the data signal into a data signal of a reproduction format and converts the converted data signal.
6 to the memory control circuit 205. The memory control circuit 205 is controlled by the main system control circuit 201 through the internal control bus 219, and transfers the data signal of the magnetic tape recording / reproducing unit format read from the main memory circuit 206 to the memory control circuit 205 by the encoder 230. To supply.

The encoder 230 encodes the magnetic tape recording / reproducing unit format data signal supplied from the memory control circuit 205 into a recording data signal, and converts the encoded recording data signal from the encoder 230 to the magnetic tape. It is supplied to the recording / reproducing unit 100.

Then, the magnetic tape recording / reproducing unit 100
Main system control circuit 201 through internal control bus 219
The recording data signal supplied to the magnetic tape recording / reproducing unit 100 is controlled by the magnetic tape recording / reproducing unit 100.
At 00, the data is recorded on a magnetic tape (not shown).

Next, in the configuration shown in FIG. 3, data recorded on a magnetic tape (not shown) is reproduced by the magnetic tape recording / reproducing section 100, and data generated based on the reproduced data is Common bus 21 from SCSII / F215
The operation in the case of transferring to the host computer 500 via 6A will be described.

In FIG. 3, a magnetic tape recording / reproducing unit 100
Is the main system control circuit 20 through the internal control bus 219.
1, a recording data signal is reproduced from a magnetic tape (not shown) by the magnetic tape recording / reproducing section 100, and the reproduced recording data signal is transmitted to the magnetic tape recording / reproducing section 100.
To the decoder 240.

The decoder 240 decodes the supplied recording data signal into a data signal in a magnetic tape recording / reproducing unit format, and supplies the decoded data signal to the memory control circuit 205.

The memory control circuit 205 is controlled by the main system control circuit 201 through the internal control bus 219 to convert the data signal of the magnetic tape recording / reproducing unit format supplied from the decoder 240 to the memory control circuit 205. The data is written from the memory control circuit 205 to the main memory circuit 206.

The memory control circuit 205 is controlled by the main system control circuit 201 through the internal control bus 219, and converts the data signal of the magnetic tape recording / reproducing format read into the main memory circuit 206 into a predetermined data recording / reproducing device. Convert to format data.

The memory control circuit 205 is controlled by the main system control circuit 201 through the internal control bus 219, and reads a data signal of a predetermined format of the data recording / reproducing apparatus from the main memory circuit 206 to the memory control circuit 205. And the data compression / decompression circuit 204
To supply.

The data compression / expansion circuit 204 is controlled by the main system control circuit 201 through an internal control bus 219, and converts the data of a predetermined format supplied from the memory control circuit 205 into the data recording / reproducing apparatus. At 204, the data compression / expansion circuit 204 is through-passed without undergoing compression or expansion or compression / expansion.

The data compression / expansion circuit 204 is controlled by the main system control circuit 201 through the internal control bus 219, and is compressed or expanded by the data compression / expansion circuit 204.
Alternatively, the data compression / expansion circuit 2 without receiving compression / expansion
The data in a predetermined format of this data recording / reproducing apparatus, which has passed through the data path 04, is supplied to the SCSII / F215.

The SCSII / F 215 is controlled by the main system control circuit 201 through the internal control bus 219, and converts the data of the predetermined format supplied from the data compression / expansion circuit 204 into the SCSII / F 215. Then, the data is converted into data in the SCSI format, and the data in the predetermined format of the data recording / reproducing device converted into the SCSI format is transferred to the host computer 500 via the common bus 216A.

The data in the predetermined format of the data recording / reproducing apparatus is compressed or decompressed by the data decompression / compression circuit 204, or is passed through the data decompression / compression circuit 204 so that the data is not subjected to compression or decompression. This will be described later.

In the present invention, the data expansion / compression circuit of the data recording / reproducing apparatus as the data transmission source and the data expansion / compression circuit 204 of the data recording / reproducing apparatus as the data transfer destination are shown in FIG. The compression / expansion mode can be set from the host computer 500 in an automatic mode or a manual mode.

Next, an example of the basic operation according to the present invention in the case of the automatic mode setting will be described with reference to FIG.

In the case of this automatic mode setting, the data transfer device to which the data is to be transferred has the SCSII / F
215, data of a predetermined format generated based on the SCSI format data transferred to the data format is supplied to the data compression / expansion circuit 204, and the data compression / expansion mode when the data compression / expansion circuit 204 performs compression / expansion is set. According to the mode select command in the copy command transferred from the host computer 500, the setting is automatically performed.

On the other hand, when the setting is manually performed on the data reproducing apparatus to which the data is to be transferred, the result of the manual setting is reported to the host computer 500.

Also, when a part or all of the compression / decompression mode function of the data reproducing apparatus to which the data is to be transferred is compressed or decompressed by the data decompression / expansion circuit 204, the host computer 500 is not operated. To report to.

On the other hand, in the case of the setting in the automatic mode,
At the data transfer source, the data transfer source, first, the compression attribute designated by the mode select command in the copy command sent from the host computer 500, and the recording and playback of the magnetic tape at the data transfer source, the data transfer source, The main system control circuit 201 compares the compressed attribute data generated based on the recording data signal reproduced from the magnetic tape and added to the data of a predetermined format in the data recording / reproducing device by the unit 100.

If the result of the comparison is the same, the data recording / reproducing apparatus generates SCSI format data based on the data of the predetermined format,
The generated SCSI format data is transferred to the host computer 500 via the common bus 216A.

On the other hand, if the result of the comparison is inconsistent, the data recording / reproducing apparatus supplies data in a predetermined format to the data compression / expansion circuit 204. The data in the predetermined format of the data recording / reproducing device is compressed or decompressed so as to match the attribute specified by the mode select command, and is matched to the attribute specified by the mode select command. This new compression attribute is added to the data of
Then, the data recording / reproducing apparatus to which the new compression attribute is added generates SCSI format data from the predetermined format data, and transfers the generated SCSI format data to the host computer 500 via the common bus 216A.

Next, in the case of the setting in the automatic mode,
A copy command signal supplied from the host computer 500 to the main system control circuit 201 of the data recording / reproducing apparatus, a setting made in the data recording / reproducing apparatus based on the copy command signal, and a specific example of the operation of the data recording / reproducing apparatus based on the setting Will be described with reference to the examples shown in FIGS. 4 to 7 and the flowcharts shown in FIGS.

First, the host computer 500 provides the main system control circuit 201 of the data recording / reproducing apparatus with the system control circuit 201 for the compression / expansion mode which is hexadecimal data given as one of the copy command signals. The determination will be described with reference to FIG.

The hexadecimal data supplied from the host computer 500 to the main system control circuit 201 of the data recording / reproducing apparatus is stored in a step h1.
In this case, when the time is 00h, the main system control circuit 201 determines the mode in which the application of compression is prohibited, and proceeds to step a. If the step h1 is other than 00h, the process proceeds to step h2.

In step h2, if it is 01h, a mode for compressing with the default value of the device;
The main system control circuit 201 makes a determination and proceeds to step b input. If it is determined in step h2 that it is not 01h, the process proceeds to step h3.

If it is 80h in step h3, the main system control circuit 201 determines the through mode and proceeds to step c.
If it is determined other than that, the process proceeds to step h4.

If it is 81h in step h4, the main system control circuit 201 determines the compression / expansion mode, and proceeds to step d.
In the case where it is determined in step 4 that it is other than 81h, the mode for inhibiting the application of the compression described above and the main system control circuit 2
01 determines and proceeds to step a.

Next, the settings on the data recording / reproducing apparatus side and the operation based on the settings in the respective compression modes specified in steps a to d shown in FIG. 9 will be described.

First, if the hexadecimal data supplied from the host computer 500 to the system control circuit 201 of the data recording / reproducing apparatus is 00h, that is, a mode in which application of compression is prohibited, the system control circuit 20
The case determined in step 1 will be described with reference to FIG.

FIG. 10 is a flowchart showing an example of the flow of the determination in step a in the main system control circuit 201.

In FIG. 10, from step a to step a
In step a1, it is determined whether the data recording / reproducing apparatus is set to a mode for writing data (in the case of Yes) or a mode for reading data (in the case of No). As a result, when the data recording apparatus is set to the data writing mode, the process proceeds to step a2, and when the data recording device is set to the data reading mode, the process proceeds to step a3.

In step a3, the main system control circuit 201 of the data recording / reproducing apparatus determines whether or not the data read from the data recording / reproducing apparatus in the data reading mode is compressed. If the read data is not compressed, the process proceeds to step a5.

Therefore, when the data recording / reproducing apparatus is set to the data write mode in which the application of the compression is prohibited, the process proceeds to step a2, and the data recording mode is set to the mode for recording the transferred data without compression. Set the playback device.

In the data read mode in which the application of compression is prohibited, if the reproduced data is compressed, the process proceeds to step a4, and the operation of decompressing and transferring the reproduced data is performed. This data recording / reproducing device is set.

Further, in the data reading mode in which the application of compression is prohibited, if the reproduced data is not compressed, the process proceeds to step a5, and the reproduced data is transferred without compression or expansion. The data recording / reproducing apparatus is set to perform the operation.

First, in the data write mode in which application of compression is prohibited, the host computer 500 designates recording of data without compression. In step a2, data recording / reproduction as a data transfer destination is performed. An example of the operation of the apparatus will be described in the case where the data recording / reproducing apparatus 1B is a side that writes this data.

In step a2, the main system control circuit 201 of the data recording / reproducing apparatus 1B sets the data recording / reproducing apparatus 1B side so as to be able to perform the signal processing indicated by the arrows V1 and V2 in FIG. Set.

The SCSII / F 215 of the data recording / reproducing apparatus 1B set as described above is controlled by the main system control circuit 201 through the internal control bus 219,
SCSII / F215 from host computer 500
In the SCSII / F 215, the data in the SCSII format transferred through the common bus 216A is
The data recording / reproducing device converts the data into a predetermined format, and supplies the data having the predetermined format to the compression / expansion circuit 204.

The compression / expansion circuit 204 is controlled by the main system control circuit 201 through the internal control bus 219, and converts the data of a predetermined format supplied from the SCSII / F 215 into the data recording / reproducing apparatus.
The compression / expansion circuit 204 passes through the compression / expansion circuit 204 in a state where neither compression nor decompression is performed, and the data recording / reproducing apparatus, which passes through the compression / expansion circuit 204 in this way, stores the data in a predetermined format into the memory control circuit 201. To supply.

The memory control circuit 201 is controlled by the main system control circuit 201 through the internal control bus 219, and is supplied from the compression / expansion circuit 204 to the memory control circuit 201, the data not subjected to the compression / expansion. The recording / reproducing device writes data in a predetermined format from the memory control circuit 201 to the main memory 206.

The memory control circuit 201 is controlled by the main system control circuit 201 through the internal control bus 219 and written into the main memory circuit 206. The data recording / reproducing device, which has not been subjected to the compression or decompression, converts the data of a predetermined format into a data signal of a magnetic tape recording / reproducing unit format, reads the data signal of the magnetic tape recording / reproducing unit format from the main memory 206, and 230.

The encoder 230 converts the data signal of the magnetic tape recording / reproducing section format supplied from the memory control circuit 201 into a recording data signal, and converts the recording data signal from the encoder 230 to the magnetic tape recording / reproducing. To the unit 100.

The magnetic tape recording / reproducing section 100
Is controlled by the main system control circuit 201 through the internal control bus 219, and records the recording data signal supplied from the encoder 230 on a magnetic tape (not shown) of the magnetic tape recording / reproducing unit 100.

According to the above setting and operation, in the data recording / reproducing apparatus 1B, the transferred data is written in the main memory 206 without compression, and
6 is supplied to the magnetic tape recording / reproducing unit 100 to be recorded on a magnetic tape (not shown) of the magnetic tape recording / reproducing unit 100. The operation of the data recording / reproducing apparatus 1B can be matched with the specified data write mode in which the application of compression is prohibited.

When the host computer 500 transfers this data to the data recording / reproducing apparatus 1B, the host computer 500 issues a command that the transfer data is a compressed data signal.
The data is transmitted to the data recording / reproducing apparatus 1B as a part of the copy command.
On the B side, the data recording / reproducing apparatus 1B side main system control circuit 201 determines, based on this command, the attribute that the data is compressed data, even though the data is not compressed by the compression / expansion apparatus 204. Automatically.

Next, when the host computer 500 specifies the data read mode in which the application of compression is prohibited, the data read mode, that is, the data read from the data recording / reproducing apparatus which is the data transfer source is compressed. The operation of step a3 for determining whether the data has been compressed or not compressed will be described.

As an example, when the data recording / reproducing apparatus 1A is on the data reading side, that is, when it is the data transfer source, the main system control circuit 201 flows in step a3 by the arrow S1 in FIG. The data recording / reproducing apparatus 1 is set to be in a state where the signal processing shown in FIG.
Set A side.

The magnetic tape recording / reproducing section 100 of the data recording / reproducing apparatus 1A set in this way is controlled by the main system control circuit 201 through the internal control bus 219, and the magnetic tape of the magnetic tape recording / reproducing section 100 is (Not shown), and reproduces the recorded data signal.
To supply.

The decoder 240 decodes the recording data signal supplied from the magnetic tape recording / reproducing unit 100 to the decoder 240 into a data signal in a magnetic tape recording / reproducing unit format, and decodes the decoded magnetic tape recording / reproducing data. The data signal of the reproduction section format is supplied to the memory control circuit 205.

The memory control circuit 205 is controlled by the main system control circuit 201 through the internal control bus 219, so that the decoder 240
The main memory circuit 206 reads the data signal of the magnetic tape recording / reproducing section format supplied to the main memory circuit 206.

The memory control circuit 205 is controlled by the main system control circuit 201 through the internal control bus 219, and the data signal of the magnetic tape recording / reproducing unit format read into the main memory circuit 206 is compressed. The main memory circuit 2 determines whether or not it is a data signal.
The determination is made based on the data indicating the compression attribute recorded as a part of the data signal of the magnetic tape recording / reproducing unit format, which has been read in step 06.

As a result of this determination, when it is determined that the data signal of the magnetic tape recording / reproducing section format is compressed, the main system control circuit 201 controls the operation of the data recording / reproducing apparatus to decompress the data signal. Then, the operation is set to the operation of step a4 specified by the host computer 500 so as to perform the transfer.

As an example, when the data recording / reproducing apparatus 1A is on the data reading side, that is, when it is the data transfer source, as a result of this determination, the data recording / reproducing apparatus 1A
The main system control circuit 201 sets the data recording / reproducing apparatus 1A to the operation of step a4 which is in the signal processing state indicating the flow in S2 in FIG.

The memory control circuit 205 on the side of the data recording / reproducing apparatus 1A set in this way is connected to the internal control bus 21.
9 is controlled by the main system control circuit 201 through
The main memory circuit 206 converts the data signal of the magnetic tape recording / reproducing unit format read in the signal processing flow S1 into data of a predetermined format of the data recording / reproducing device.

The memory control circuit 205 is controlled by the main system control circuit 201 through the internal control bus 219, reads out data of a predetermined format of the data recording / reproducing apparatus from the main memory circuit 206, and stores the data in the data compression / decompression circuit 204. To supply.

The data compression / expansion circuit 204 is controlled by the main system control circuit 201 through the internal control bus 219, and reads out the data of a predetermined format read from the main memory circuit 206 and supplied thereto. The data is expanded and decompressed by the data compression / expansion circuit 204, and the expanded data signal of the magnetic tape recording / reproducing unit format is supplied to the SCSII / F215.

The SCSII / F 215 is controlled by the main system control circuit 201 through the internal control bus 219 to convert the expanded data signal of the magnetic tape recording / reproducing section format supplied from the data compression / expansion circuit 204 into the SCSII format. And converts the converted SISII format data to SCSII data.
/ F 215 to the host computer 500 via the common bus 216A.

Therefore, the data in the predetermined format of the data recording / reproducing apparatus, which is generated based on the compressed recording data signal, is supplied to the data compression / expansion circuit 204 and decompressed, and is converted into SCSII format data.
The data can be transferred from the CSII / F 215 to the host computer 500 via the common bus 216A, and the operation of step a4 can be performed by the data recording / reproducing apparatus 1A.

When it is determined that the data signal of the magnetic tape recording / reproducing section format is not compressed, the main system control circuit 201
The operation of the data recording / reproducing apparatus is set at step a5 specified by the host computer 500.

As an example, when the data recording / reproducing apparatus 1A is on the data reading side, that is, when it is the data transfer source, the main system control circuit 201 of the data recording / reproducing apparatus 1A sets the step a5 as shown in FIG. To W
1 and W2, a signal processing state indicating a flow, that is, unlike the processing flow S1 of the processing flow S1 of FIG. 5 and the processing flow S1 of FIG.
Then, the data recording / reproducing apparatus 1A is set so that the flow W2 of the processing without performing the data compression / decompression is performed.

The memory control circuit 205 on the side of the data recording / reproducing apparatus 1A set as described above is connected to the internal control bus 21.
9 is controlled by the main system control circuit 201 through
The data signal of the magnetic tape recording / reproducing apparatus format read by the main memory circuit 206 in the same processing flow W1 as the signal processing flow S1 is converted into data of a predetermined format of the data recording / reproducing apparatus.

The memory control circuit 205 is controlled by the main system control circuit 201 through the internal control bus 219, reads out data of a predetermined format of the data recording / reproducing apparatus from the main memory circuit 206, and reads the data in the main memory circuit 206. The data read from the data recording / reproducing apparatus and having a predetermined format is supplied to the data compression / expansion circuit 204.

This data compression / expansion circuit 204 is controlled by the main system control circuit 201 through the internal control bus 219, read out from the main memory circuit 206, and supplied to the data compression / expansion circuit 205. Data of a predetermined format is passed through the data compression / expansion circuit 205 in a state where compression / expansion is not performed, and the data of the predetermined format of the data recording / reproducing apparatus passed through the SCSII / F215
To supply.

The SCSII / F 215 is controlled by the main system control circuit 201 through the internal control bus 219 and supplied from the data compression / decompression circuit 204.
This data recording / reproducing device, which has not been subjected to compression and decompression through this pass-through, is used to convert the data of the predetermined format into SCS data.
The data is converted into data of the I format standard, and the data of the SCSI format standard is converted from the SCSI II / F 215 through the common data bus 216 into the host computer 50.
0.

Thus, according to this setting, data of a predetermined format of the data recording / reproducing device generated based on the uncompressed recording data signal can be transferred to the data compression / expansion circuit 20.
After passing through without compressing / expanding at 5,
Convert to SCSII format data,
/ F 215 to the host computer 500 via the common bus 216A, and the operation of the data recording / reproducing apparatus 1A can be made to coincide with the operation of step a5 instructed by the host computer 500.

Next, the hexadecimal data supplied from the host computer 500 to the main system control circuit 201 of the data recording / reproducing apparatus is output to the host system 500 in step h1.
h in the next step, that is, 01h, that is, in the case where the main system control circuit 201 determines that the mode is the default compression mode of the device,
This will be described with reference to FIG.

FIG. 11 is a flowchart showing an example of the flow of the judgment in step b in the main system control circuit 201.

In FIG. 11, steps b to b
Then, at step b1, whether the data recording / reproducing apparatus controlled by the main system control circuit 201 is set to a mode for writing data (in the case of Yes),
Or do you set the mode to read data (N
o), and as a result of this determination, the process proceeds to step b2 when the data recording apparatus is set to the data writing mode, and to step b3 when the data recording device is set to the data reading mode.

Then, in step b3, the main system control circuit 201 of the data recording / reproducing apparatus determines whether or not the data read from the data recording / reproducing apparatus in the data reading mode is compressed. If the read data is not compressed, the process proceeds to step b5.

Therefore, when the data recording / reproducing apparatus is set to the data write mode for compressing the device default, the process proceeds to step b2 to transfer the data to the mode for compressing and recording the transferred data with the device default value. The data recording / reproducing device to be used is set.

If the reproduced data has been compressed in the data reading mode with the default value being compressed, the flow advances to step b4 to switch the data transfer source mode to a mode in which the reproduced data is expanded and then transferred. Is set.

Further, if the reproduced data is not compressed in the data reading mode with the default value being compressed, the process proceeds to step b5, where the data is transferred to the mode in which the reproduced data is transferred without being expanded. Set the original data recording / reproducing device.

First, from the host computer 500, if the data recording / reproducing apparatus is set to the mode for writing data and the mode for compressing and recording the transferred data is set, the main system control circuit 201 The operation of the data recording / reproducing device serving as the data transfer destination in the determined step b2 will be described as an example in the case where the data recording / reproducing device 1B is on the data writing side.

In step b2, the main system control circuit 201 of the data recording / reproducing apparatus 1B sets the data recording / reproducing apparatus 1B side so that the signal processing shown by the arrows T1 and T2 in FIG. 7 can be performed. Set.

The SCSII / F 215 of the data recording / reproducing apparatus 1B set as described above is connected to the internal control bus 219.
The SCSII / F 215 converts the data in the SCSII format transferred from the host computer 500 to the SCSII / F 215 through the common bus 216A into data in the predetermined format by the main system control circuit 201. And
The converted data in the predetermined format of the data recording / reproducing device is supplied to the compression / expansion circuit 204.

Next, the compression / expansion circuit 204 is controlled by the main system control circuit 201 through the internal control bus 219 and supplied to the compression / expansion circuit 204 from the SCSII / F 215. From the data of the format, the compressed data of the device default value recorded in this data is read.

The compression / expansion circuit 204 is controlled by the main system control circuit 201 through the internal control bus 219, and based on the read device default value compressed data, the data recording / reproducing apparatus has a predetermined format of data. The data is compressed and supplied to the memory control circuit 201 with the compressed data of a predetermined format.

Next, the memory control circuit 205 is controlled by the main system control circuit 201 through the internal control bus 219 to transfer the data in the predetermined format of the data recording / reproducing apparatus which has performed the compression of the device default value.
Write to the main memory circuit 206.

Next, the memory control circuit 205 is controlled by the main system control circuit 201 through the internal control bus 219 to write the data in the main memory circuit 206 and compress the device default value. The data of the predetermined format is converted into a data signal of a magnetic tape recording / reproducing device format, and the data signal of the magnetic tape recording / reproducing device format is read out from the main memory 206 and read from the encoder 2.
30.

Next, the encoder 230 converts data of a predetermined format of the data recording / reproducing device into a recording data signal, and supplies the recording data signal from the encoder 230 to the magnetic tape recording / reproducing unit 100.

The magnetic tape recording / reproducing section 100 is controlled by the main system control circuit 201 through the internal control bus 219, and transmits the recording data signal supplied from the encoder 230 to the magnetic tape (not shown) of the magnetic tape recording / reproducing section 100. Record).

By this operation, the recording data signal generated based on the data subjected to the device default compression is supplied to the magnetic tape recording / reproducing unit 100, where the magnetic tape (shown in FIG. ), The processing in the data recording / reproducing apparatus 1B can be matched with the mode for compressing the default value of the device.

The default value of the device means that when a magnetic tape (not shown) of the magnetic tape recording / reproducing unit 100 is initialized, the data compression attribute to be recorded on the magnetic tape is recorded on the tape in advance. The compression attribute data that determines the initial value of the compression attribute of data to be recorded on the tape, and refers to data added to the recording data as a part of the data recorded on the tape.

Next, it is determined whether the data read from the data recording / reproducing apparatus in the data reading mode is compressed or not.
The operation of step b3 for determining which one is the following will be described.

As an example, when the data recording / reproducing apparatus 1A reads data, that is, becomes a data transfer source,
In step b3, the main system control circuit 201 sets the data recording / reproducing apparatus 1A so that the signal processing indicated by the arrow S1 in FIG. 5 can be performed.

The data recording / reproducing apparatus 1 set as described above
The A-side magnetic tape recording / reproducing unit 100 includes an internal control bus 2
19, controlled by the main system control circuit 201,
The recording data signal recorded on the magnetic tape (not shown) of the magnetic tape recording / reproducing unit 100 is reproduced,
The reproduced recording data signal is supplied to the decoder 240.

The decoder 240 converts the recording data signal supplied from the magnetic tape recording / reproducing section 100 into
The data signal is decoded into a magnetic tape recording / reproducing unit format data signal, and the decoded data signal of the magnetic tape recording / reproducing unit format is supplied to the memory control circuit 205.

The memory control circuit 205 is controlled by the main system control circuit 201 through the internal control bus 219, so that the decoder 240
Is read into the main memory circuit 206.

The memory control circuit 205 is controlled by the main system control circuit 201 through the internal control bus 219, and compresses the data signal of the magnetic tape recording / reproducing unit format read into the main memory circuit 206. It is determined from the data indicating the compression attribute that is read as a part of the data signal of the magnetic tape recording / reproducing unit format, which is read into the main memory circuit 206.

As a result of this determination, when it is determined that the data signal of the magnetic tape recording / reproducing unit format is compressed, the main system control circuit 201 controls the operation of the data recording / reproducing apparatus 1A by the host computer 500. Is set in step b4 specified by

As an example, when the data recording / reproducing apparatus 1A is on the data reading side, the data recording / reproducing apparatus 1A
In step b4, the main system control circuit 201 of A sets the data recording / reproducing apparatus 1A so that the processing state shown in FIG. 5 indicates the flow in S2.

The memory control circuit 205 on the side of the data recording / reproducing apparatus 1A set in this way is connected to the internal control bus 21.
9 is controlled by the main system control circuit 201 through
The data signal of the magnetic tape recording / reproducing unit format read by the main memory circuit 206 in the processing flow S1 is converted into data of a predetermined format of the data recording / reproducing device.

The memory control circuit 205 is controlled by the main system control circuit 201 through the internal control bus 219 to read data in a predetermined format of the data recording / reproducing apparatus from the main memory circuit 206 and send the data to the data compression / decompression circuit 204. Supply.

The data compression / expansion circuit 204 is controlled by the main system control circuit 201 through the internal control bus 219, and reads out the data of a predetermined format read from the main memory circuit 206 and supplied thereto, and Expanded by the data compression / expansion circuit 204,
The decompressed data in the data recording / reproducing apparatus is supplied to the SCSII / F 215 in a predetermined format.

The SCSII / F 215 is controlled by the main system control circuit 201 through the internal control bus 219, and transmits the expanded data signal of the magnetic tape recording / reproducing unit format supplied from the data compression / expansion circuit 204. The data is converted to SCSII format data, and the SCSII format data is converted to SCSII format data.
/ F 215 to the host computer 500 via the common bus 216A.

Therefore, by this operation, in the mode for compressing the data to the default value of the device, even the data compressed by the default value of the device can be expanded and transferred to the host computer 500. The operation of the data recording / reproducing apparatus 1A serving as the data transfer source can be matched with the mode in which the application of compression is prohibited.

Next, when the main system control circuit 201 determines that the data signal of the magnetic tape recording / reproducing section format is not compressed as a result of the judgment, the main system control circuit 201 executes the data recording / reproducing. The operation of the apparatus is set at step b5 specified by the host computer 500.

As an example, when the data recording / reproducing apparatus 1A is on the data reading side, that is, when it is the data transfer source, the main system control circuit 201 of the data recording / reproducing apparatus 1A sets the step b5 in FIG. To W
5 is different from the flow W1 of the same process as the flow S1 in FIG. 5 and the flow S1 of the process in FIG.
The data recording / reproducing apparatus 1A is set so that the flow W2 in which the data compression / expansion is not performed is performed.

The memory control circuit 205 of the data recording / reproducing apparatus 1A set as described above is controlled by the main system control circuit 201 through the internal control bus 219, and the processing flow S1 is sent to the main memory circuit 206. The data signal of the magnetic tape recording / reproducing unit format read in the same processing flow W1 is converted into data of a predetermined format of the data recording / reproducing apparatus.

Next, the memory control circuit 205 is controlled by the main system control circuit 201 through the internal control bus 219 to read data of a predetermined format of the data recording / reproducing apparatus from the main memory circuit 206,
The data in the predetermined format read from the main memory circuit 206 is supplied to the data compression / expansion circuit 204.

The data compression / expansion circuit 204 is controlled by the main system control circuit 201 through the internal control bus 219, and converts the data in the predetermined format supplied to the data compression / expansion circuit 204 into a data compression / expansion signal. The circuit 204 passes through the data recording / reproducing apparatus in a predetermined format without performing compression / expansion.
215.

The SCSII / F 215 is controlled by the main system control circuit 201 through the internal control bus 219, reads out from the main memory circuit 206,
The data compression / expansion circuit 204 is passed through
The data of a predetermined format supplied to the data recording / reproducing device supplied to the I / F 215 is converted into data of the SCSI format standard, and the data of the SCSI format standard is transmitted from the SCSI II / F 215 to the host computer 500 via the common bus 216A. Forward.

Therefore, even in the mode of compressing the data to the default value of the device, the data recording / reproducing apparatus, which is generated based on the uncompressed recording data signal, uses the data of the predetermined format without performing the compression such as the default. The data can be transferred to the computer 500, and the data recording / reproducing apparatus 1A can be set to a mode in which application of compression is prohibited.

Next, in the flowchart of FIG. 10, it is determined that the hexadecimal data supplied from the host computer 500 to the system control circuit of the data recording / reproducing apparatus is not 01h in step h1, and 01h is determined in the next step h2. It will be described with reference to the flowchart of FIG. 12 when it is determined that the data is not 80h in the next step h3, that is, when it is determined that the data is hexadecimal data in the through mode.

FIG. 12 is a flowchart showing an example of a setting flow by the main system control circuit 201 based on an instruction from the host computer 500 in step c.

In FIG. 12, from step c to step c
In step c1, it is determined whether the data recording / reproducing apparatus is set to a mode for writing data (in the case of Yes) or a mode for reading data (in the case of No). As a result, when the data recording apparatus is set to the data writing mode, the process proceeds to step c2, and when the data recording device is set to the data reading mode, the process proceeds to step c3.

In step c2, the data recording / reproducing apparatus is set to the through mode in the data write mode. Therefore, the main system control circuit 201 of the data recording / reproducing apparatus transmits this transfer from the common bus 216A. Main memory 20 without compressing received data
6 is supplied to the magnetic tape recording / reproducing unit 100 to be recorded on the magnetic tape (not shown) of the magnetic tape recording / reproducing unit 100. The data recording / reproducing device that is the data transfer destination is set in the data write mode.

First, as an example of the operation of the data recording / reproducing device in step c2, the setting and operation of the data recording / reproducing device when the data recording / reproducing device 1B is on the writing side will be described.

In the step c2, the main system control circuit 201 of the data recording / reproducing apparatus 1B
The data recording / reproducing apparatus 1B is set so as to be able to perform signal processing indicating the flow by arrows V1 and V2.

The SCSII / F 215 of the data recording / reproducing apparatus 1B set as described above is connected to the internal control bus 21.
9 is controlled by the main system control circuit 201 through
SCSII / F215 from host computer 500
Then, the SCSI format data transferred through the common bus 216A is converted by the SCSI II / F 215 into data of a predetermined format of the data recording / reproducing device, and the data of the predetermined format of the data recording / reproducing device is transmitted to the compression / decompression circuit 204. Supply.

The compression / expansion circuit 204 is controlled by the main system control circuit 201 through the internal control bus 219, and converts the data of a predetermined format supplied from the SCSII / F 215 into the compression / expansion circuit. At 204, the compression / expansion circuit 204 is passed through in a state where neither compression nor decompression is performed.
5

The memory control circuit 205 is controlled by the main system control circuit 201 through the internal control bus 219, and passes the compression / expansion circuit 204 supplied from the compression / expansion circuit 204 in a state where neither compression nor expansion is performed. The data recording / reproducing apparatus writes data in a predetermined format into the main memory 206.

The memory control circuit 205 is controlled by the main system control circuit 201 through the internal control bus 219, and is transmitted from the memory control circuit 205 to the main memory 206.
This data recording / reproducing device, which has been written in the device, converts the data in a predetermined format into data in a magnetic tape recording / reproducing unit format.

The memory control circuit 205 is controlled by the main system control circuit 201 through the internal control bus 219, reads out the data signal of the magnetic tape recording / reproducing unit format from the main memory 206 to the memory control circuit 205, and The data signal of the magnetic tape recording / reproducing unit format read by the circuit 205 is supplied to the encoder 230.

This encoder 230 is provided in the main memory 20.
6 to the memory control circuit 205, converts the data signal of the magnetic tape recording / reproducing section format supplied from the memory control circuit 205 into a recording data signal, and converts the converted recording data signal into a magnetic tape recording / reproducing signal. To the unit 100.

The magnetic tape recording / reproducing section 100
Is connected to the main system control circuit 2 through the internal control bus 219.
01, the recording data signal supplied from the encoder 230 is recorded on a magnetic tape (not shown).

By these settings and operations, a recording data signal generated based on the data written in the main memory circuit 206 without compressing the transferred data is supplied to the magnetic tape recording / reproducing unit 100. The data can be recorded on a magnetic tape (not shown) of the magnetic tape recording / reproducing unit 100, so that the data recording / reproducing apparatus 1B can be set to the data write mode of the through mode specified by the host computer 500.

In step c3, the data recording / reproducing apparatus is set to the through mode in the data read mode. Therefore, the main system control circuit 201 of the data recording / reproducing apparatus sets the data recording / reproducing apparatus based on the data generated based on the recording data signal. Recording / reproducing apparatus Through-mode in which data of a predetermined format is passed through in a state where data is not compressed / expanded by data compression / expansion circuit 205, regardless of whether the data is compressed or not, and transmitted to common bus 216A. Next, this data recording / reproducing apparatus is set.

Next, as an example of the operation of the data recording / reproducing device in step c3, the setting and operation when the data recording / reproducing device 1A is the data reading side, that is, the data transfer source, will be described.

At step c3, the main system control circuit 201 of the data recording / reproducing apparatus 1A first
The data recording / reproducing apparatus 1A is set so as to be in a state where signal processing indicating a flow in W1 and W2 can be performed.

The magnetic tape recording / reproducing section 100 of the data recording / reproducing apparatus 1A thus set is controlled by the main system control circuit 201 through the internal control bus 219, and the recording / reproducing of the magnetic tape of the data recording / reproducing apparatus 1A is performed. The recording data signal recorded on the magnetic tape (not shown) of the unit 100 is reproduced, and the reproduced recording data signal is supplied to the decoder 240.

The decoder 240 decodes the reproduced recording data signal supplied from the magnetic tape recording / reproducing unit 100 into a data signal of the magnetic tape recording / reproducing unit format, and decodes the data of the magnetic tape recording / reproducing unit format. The signal is supplied to the memory control circuit 205.

The memory control circuit 205 is controlled by the main system control circuit 201 through the internal control bus 219, and transmits the data signal of the magnetic tape recording / reproducing unit format supplied from the decoder 240 to the memory control circuit 205. The data is read into the memory circuit 206.

The memory control circuit 205 is controlled by the main system control circuit 201 through the internal control bus 219, and converts the data signal of the magnetic tape recording / reproducing unit format read into the main memory circuit 206 into a predetermined data recording / reproducing device. Convert to format data.

The memory control circuit 205 is controlled by the main system control circuit 201 through an internal control bus 219 to read data of a predetermined format from the data recording / reproducing device from the main memory circuit 206, and read the read data recording / reproducing device. The data in a predetermined format is supplied to the data compression / expansion circuit 204.

The data compression / expansion circuit 205 is controlled by the main system control circuit 201 through the internal control bus 219, and is read from the main memory circuit 206 and supplied to the data compression / expansion circuit 204. Recording and playback device
The data compression / expansion circuit 204 does not perform compression / expansion.
This data recording / reproducing apparatus, which passes through the data recording / reproducing apparatus without performing compression / expansion, supplies the data to the SCSII / F215.

The SCS II / F 215 is controlled by the main system control circuit 201 through the internal control bus 219, and the SCS II / F 215
The data of the predetermined format supplied to the II / F 215 and passed through the data compression / expansion circuit 204 is converted into the data of the SCSI format standard, and the data of the SCSI format standard is converted from the SCSI II / F 215 into the SCSI format standard data. The data is transferred to the host computer 500 via the common data bus 216.

With these settings and operations, the data compression / expansion circuit 205 performs compression / expansion of data in a predetermined format generated by the data recording / reproducing apparatus based on the recording data signal, regardless of whether the data is compressed or not. The data recording / reproducing apparatus 1A can be set to the data reading mode in the through mode specified by the host computer 500 by passing through the common bus 216A without passing through.

Next, in the flowchart of FIG. 10, it is determined that the hexadecimal data supplied from the host computer 500 to the system control circuit of the data recording / reproducing apparatus is not 01h in step 1h, and 01h is determined in the next step h2. It is determined that the data is not 80h in the next step h3, and it is also determined that the data is 81h in the next step h4, that is, hexadecimal data in the compression / decompression mode, with reference to the flowchart of FIG. explain.

FIG. 13 is a flowchart showing an example of the flow of setting by the main system control circuit 201 based on an instruction from the host computer 500 in step d.

In FIG. 13, from step d to step d
In step d1, whether the data recording / reproducing apparatus is set to a mode for writing data (in the case of Yes) or a mode for reading data (in the case of No) is determined. If the result of this determination is that the data recording device is to be set to the data writing mode, the process proceeds to step d2, and if the data recording device is set to the data reading mode, the process proceeds to step d3.

In step d2, the data recording / reproducing apparatus is set to the compression mode in the data writing mode. Therefore, the main system control circuit 201 of the data recording / reproducing apparatus supplies the data from the common bus 216A. The received data is compressed and the magnetic tape recording / reproducing unit 10
This data recording / reproducing apparatus is set to a mode for recording to 0.

First, as an example of the operation of the data recording / reproducing device in step d2, the data recording / reproducing unit 1
The setting and operation of the data recording / reproducing apparatus 1B when B is the data writing side, that is, the data transfer destination, will be described.

The main system control circuit 201 of the data recording / reproducing apparatus 1B determines in step d2
The data recording / reproducing apparatus 1B is set so as to be in a state where signal processing indicated by arrows T1 and T2 in FIG. 7 can be performed.

The SCSII / F 215 of the data recording / reproducing apparatus 1B set in this way is connected to the internal control bus 21.
9 is controlled by the main system control circuit 201 through
SCSII / F215 from host computer 500
In the SCSII / F 215, the data in the SCSII format transferred through the common bus 216A is
The data recording / reproducing device converts the data into a predetermined format, and supplies the data having the predetermined format to the compression / expansion circuit 204.

The compression / expansion circuit 204 is controlled by the main system control circuit 201 via the internal control bus 219, and converts the data of a predetermined format supplied from the SCSII / F 215 into the compression / expansion circuit. The data is compressed in 204, and the compressed data of the predetermined format is supplied to the memory control circuit 205.

The memory control circuit 205 is controlled by the main system control circuit 201 through the internal control bus 219 to transfer the compressed data of the predetermined format supplied from the compression / expansion circuit 204 to the data recording / reproducing apparatus. Write to the main memory circuit 206.

The memory control circuit 205 is controlled by the main system control circuit 201 through the internal control bus 219, and is transmitted from the memory control circuit 205 to the main memory circuit 2
The compressed data recording / reproducing apparatus writes the data of the predetermined format into the data signal of the magnetic tape recording / reproducing unit format.

The memory control circuit 205 is controlled by the main system control circuit 201 through the internal control bus 219 to read the data signal of the magnetic tape recording / reproducing unit format from the main memory circuit 206 to the memory control circuit 205, The data signal of the magnetic tape recording / reproducing unit format read to the memory control circuit 205 is supplied to the encoder 230.

This encoder 230 is provided in the main memory 20.
6 to the memory control circuit 205, converts the data signal of the magnetic tape recording / reproducing section format supplied from the memory control circuit 205 into a recording data signal, and converts the converted recording data signal into a magnetic tape recording / reproducing signal. To the unit 100.

The magnetic tape recording / reproducing section 100
Is connected to the main system control circuit 2 through the internal control bus 219.
01, the recording data signal supplied from the encoder 230 is recorded on a magnetic tape (not shown).

According to these settings and operations, a data signal generated by compressing the transferred data and generating the data based on the data written in the main memory circuit 206 is supplied to the magnetic tape recording / reproducing unit 100, The data can be recorded on a magnetic tape (not shown) of the tape recording / reproducing unit 100, so that the data recording / reproducing apparatus 1B can be set to the data write mode of the data compression mode specified by the host computer 500.

Then, in step d3, the data recording / reproducing apparatus is set to the decompression mode in the data reading mode. Therefore, the main system control circuit 201 of the data recording / reproducing apparatus sets the magnetic tape recording / reproducing section 10
0, the data of the predetermined format generated based on the recorded data reproduced from the
The data recording / reproducing apparatus is set to a mode in which the data in the SISI format converted into the data in the I format is transferred to the host computer 500 via the common bus 216A.

Next, as an example of the operation of the data recording / reproducing device in step d3, the setting and operation when the data recording / reproducing device 1A is the data reading side, that is, the data transfer source, will be described. .

At step d3, the main system control circuit 201 of the data recording / reproducing apparatus 1A first sets the data recording / reproducing apparatus 1A so as to be in the signal processing state shown by the flow in S1 and S2 in FIG. Set the side.

The magnetic tape recording / reproducing section 100 of the data recording / reproducing apparatus 1A thus set is controlled by the main system control circuit 201 through the internal control bus 219, and the magnetic tape recording / reproducing of the data recording / reproducing apparatus 1A is controlled. The compressed recording data signal recorded on the magnetic tape (not shown) of the unit 100 is reproduced, and the reproduced compressed recording data signal is supplied to the decoder 240.

The decoder 240 decodes the reproduced compressed recording data signal supplied from the magnetic tape recording / reproducing unit 100 into a data signal of the magnetic tape recording / reproducing unit format, and decodes the data of the magnetic tape recording / reproducing unit format. The signal is supplied to the memory control circuit 205.

The memory control circuit 205 is controlled by the main system control circuit 201 through the internal control bus 219, so that the decoder 240
The data signal of the magnetic tape recording / reproducing unit format supplied to the main memory circuit 206 is read.

The memory control circuit 205 is controlled by the main system control circuit 201 through the internal control bus 219, and converts the compressed data signal of the magnetic tape recording / reproducing unit format read into the main memory circuit 206 into a data recording / reproducing device predetermined data. To format data.

The memory control circuit 205 is controlled by the main system control circuit 201 through the internal control bus 219 to read data of a predetermined format of the data recording / reproducing device from the main memory circuit 206, Is supplied to the data compression / decompression circuit 204.

The data compression / expansion circuit 204 is controlled by the main system control circuit 201 through the internal control bus 219, read from the main memory circuit 206, and supplied to the data compression / expansion circuit 204. The data in a predetermined format of the device is expanded by the data compression / expansion circuit 204, and the expanded data in the predetermined format of the data recording / reproducing device is converted to a SCSI.
Supply to I / F215.

The SCSI / F 215 is controlled by the main system control circuit 201 through the internal control bus 219, and receives the SCSI signal from the data compression / decompression circuit 205.
The decompressed data in the data recording / reproducing device in a predetermined format supplied to the I / F 215
The data is converted into data of the format standard, and the data of the SCSI format standard is transferred from the SCSI II / F 215 to the host computer 500 via the common bus 216A.

With these settings and operations, the data recording / reproducing device, which has been generated based on the compressed recording data signal and has a predetermined format, can transmit the data to the data compression / expansion circuit 2.
04, the data recording / reproducing apparatus expands the compressed data of a predetermined format in the SCSII
/ F 215, where the data recording / reproducing device converts the data of a predetermined format into SCSI format data, and converts the data converted into the SCSI format data from the SCSI II / F 215 to the common bus 21.
6A, the data can be transferred to the host computer 500, and the compression / decompression mode specified by the host computer 500 can be matched.

Next, in the examples shown in FIGS. 4, 5, 6, and 7, the data compression / expansion unit of the data recording / reproducing apparatus is used as if it were a peripheral device of another data recording / reproducing apparatus. This example will be described with reference to FIG.

In FIG. 8, the system control circuit 201 on the data recording / reproducing apparatus 1C side includes a host computer 50
8 based on the copy command sent from 0.
The data recording / reproducing apparatus 1C is set so that signal processing indicating the flow can be performed in steps 1 and R2.

The main system control circuit 201 controls the SCSI II / F 215 through the internal control bus 219, and the SCSI transferred from the host computer 500 to the SCS 11 / F 215 through the common bus 216A.
Format data is transferred to this SCSII / F215
Then, the data is converted into data of a predetermined format of the data recording / reproducing device, and the converted data of the predetermined format of the data recording / reproducing device is supplied to the data compression / expansion circuit 204.

The main system control circuit 201 controls the data compression / expansion circuit 204 through the internal control bus 219, and according to the compression attribute based on the copy command sent from the host computer 500, the converted data recording / reproducing device The compression / decompression or through-pass processing is performed on the data of the format described above, and the data of the predetermined format of the data recording / reproducing apparatus that has performed this processing is supplied to the memory control circuit 205. Next, the main system control circuit 201 controls the memory control circuit 205 through the internal control bus 219, and writes the data in the predetermined format of the data recording / reproducing apparatus that has performed this processing into the main memory.

The main system control circuit 201, based on the copy command sent from the host computer 500,
By controlling the memory control circuit 205 through the internal control bus 219, the data recording / reproducing device, which has been written in the main memory 206, reads out data of a predetermined format,
The read data of the predetermined format is supplied to the data compression / decompression circuit 204.

The main system control circuit 201 controls the data compression / decompression circuit 204 through the internal control bus 219, and transfers the data of a predetermined format supplied from the memory control circuit 205 to the host computer 500. In accordance with the compression attribute based on the copy command sent from the server, expansion, compression, or through-pass processing is performed, and data in a predetermined format of the data recording / reproducing apparatus subjected to the processing is supplied to the SCSII / F 215.

Next, the main system control circuit 201 transmits the data via the internal control bus 219 to the SCS II / F 215.
Is controlled, and the data of the format of the data recording / reproducing apparatus that has performed this processing is transmitted to the SCII / F 215 by the SC
The host computer 500 converts the data to the SCSI format from the SCSI II / F 215 through the common bus 216A.
To be forwarded to

That is, according to the example shown in FIG.
In the data recording / reproducing apparatus 1A or 1B shown in FIGS. 5, 6 and 7, the data compression / decompression unit of another data recording / reproducing apparatus 1C is shown in FIGS. 4, 5, 6 and 7. The data recording / reproducing devices 1A and 1B can be used as peripheral devices of 1B. Therefore, the data compression / decompression is provided to some of the data recording / reproducing devices connected via the common bus 216A. Even if there is a device which does not have a unit or does not operate, as shown in FIG. 8, the data compression / decompression unit of the data recording / reproducing device is used as a data compression / decompression unit of another data recording / reproducing device. It can be used.

In the case of the setting in the automatic mode described with reference to FIGS. 4, 5, 6, 7 and 8, the data compression / expansion circuit 204 of the data recording / reproducing apparatus to which the data is transferred is provided. What kind of compression / expansion is performed in the data compression / expansion circuit 204 of the data recording / reproducing apparatus, which is a data transfer source side,
It has been described that the setting is performed by the copy command from the host computer 500.

However, in the present invention, the present invention is not limited to this. The data compression / decompression mode of the data recording / reproducing apparatus of the transfer destination can be changed from the data recording / reproducing apparatus of the transfer source to the host computer. The data compression / decompression mode of the data recording / reproducing apparatus of the transfer source may be set directly without the intervention of the host computer 500 from the data recording / reproducing apparatus of the transfer destination. Of course, it may be set directly.

Next, the manual setting of the compression attribute will be described. In the manual setting of the compression attribute, the setting of the compression attribute at the data transfer source and the compression attribute at the data transfer destination are performed manually or by the host computer 500.
The settings made in the data recording / reproducing apparatus based on the copy command signal in the case of the setting in the automatic mode described above, and the setting, except that the setting can be made independently by the copy commands sent from the user. The operation of the data recording / reproducing apparatus based on the examples shown in FIGS. 4, 5, 6, 7 and 8 and FIG.
13 to FIG. 13 and described with reference to the flowchart, further description will be omitted.

The operations in the automatic mode and the manual mode in each of the examples shown in FIGS. 4, 5, 6, 7 and 8 are described with reference to the configurations and data flow shown in FIGS. The operation is not limited to the above, and it goes without saying that the device may be operated on various other configurations and data flows.

In each of the directions of the data recording / reproducing apparatus serving as a data transfer source and the data recording / reproducing apparatus serving as a transfer destination, the respective data decompression / compression circuits are directly transmitted without passing through the host computer 500. Of course, the compression / expansion mode of 204 may be set in an automatic mode or a manual mode.

The function of the data compression / expansion circuit 205 of the data recording / reproducing apparatus of the transfer destination is checked from the host computer 500, and the function of the data compression / expansion circuit 205 of the data recording / reproducing apparatus of the transfer destination is determined by the function of the source. When the function is lower than the function of the data compression / expansion circuit 205 of the data recording / reproducing apparatus, the range of the compression attribute instructed from the host computer 500 to the data recording / reproducing apparatus of the transfer source is as follows.
Of course, the function may be limited to the range of the function of the data compression / decompression circuit 205 of the data recording / reproducing apparatus at the transfer destination.

The operation of limiting the range of functions of the data compression / expansion circuit 205 of the data recording / reproducing apparatus at the transfer source is described below.
Needless to say, the transfer may be performed directly from the data recording / reproducing apparatus at the transfer destination.

In this example, the number of data recording / reproducing devices connected by the common bus is not limited to two, but may be two.
Needless to say, any number of combinations equal to or greater than the number of pairs may be used.

Also, the type of the common bus is not limited to the SCSI standard, and it goes without saying that a common bus of any standard can be used.

Next, FIG. 14 shows an example in which the above-described data representing the compression attribute recorded as a part of the data signal is recorded in the management data recording area of the magnetic tape.
This will be described with reference to FIGS. 15, 16, 17, 18, 19, and 20.

FIG. 14 is an enlarged view showing the tape format of the front end side of the magnetic tape 111, that is, the portion wound around and fixed to the take-up reel.

In FIG. 14, a leader tape portion 601 having a length of 10 ± 0.5 meters from the physical tip 601A of the magnetic tape 111 is formed at the first portion of the tip portion. A tape running section (RUA) 602 having a length of 0.8 ± 0.05 meters from the recording operation start point 601B is formed with the end point of the part forming section 601 as a recording operation start point 601B, and the tape A management data recording area (VIST) 603 having a minimum length of 0.2 meters (90 or more recording tracks) from the end of the run-around section (RUA) 602 is formed, and the management data recording area (VIST) is formed. ) 603 records management data of the entire data recorded on the magnetic tape 111.

The management data recording area (VIST) 60
A recording margin area (PTB) 604 having a length of 0.35 ± 0.05 meters is formed following the end of the recording margin area (PTB) 604, and the tape described above follows the termination of the recording margin area (PTB) 604. An approach section (RUA) 602 is formed,
Subsequent to the end of the tape running section (RUA) 602, a management data recording area (DIT) 606 of the unit data recording area 605 described later is formed. The recording margin area (PTB) 604 described above is formed, and the tape running section (RUA) 602 described above is formed following the end of the recording margin area (PTB) 604, and the tape running section (RUA) is formed. The unit data recording area 605-1 is formed following the end portion of) 602.

Next, the recording format of the entire magnetic tape 111 will be described with reference to FIG.

In the recording format shown in FIG. 15, the recording format from the physical leading end 601A of the magnetic tape 111 to the first unit data (Data area of Volume 1) recording area 605-1 will be described with reference to FIG. This is the same recording format as that of the basic recording format unit.

[0202] Among the basic recording format units, the basic recording format unit consisting of the recording format formed from the first recording margin area (PTB) 604 to the first unit data recording area 601-1 is defined as the unit data. After the recording area 605-1, recording is sequentially and repeatedly performed, recording is performed up to the N-th unit data (Data area of Volume N) recording area 605-N, and the recording area 6
Data indicating the end of recording (Vi
The area 609 in which the rtual end of volume has been recorded is recorded, and the magnetic tape 1 is continued immediately after the end of the area 609.
A leader tape portion 607 having a length of about 15 meters from the 11 physical ends 608 is formed to form the entire format of the magnetic tape 111.

Next, a management data recording area (VIST) 60
3. The recording contents of the unit data recording areas 605-1 to N and the management data recording area (DIT) 606 of the unit data will be described.

The management data recording area (VIST) 603 is called a VSIT (Volume Set Information Table) area, in which management data of the entire data recorded on the magnetic tape is recorded.
An IST) 603 includes an area 603A, which has the data contents shown as an example in FIG. 18, and in which management data of the entire data recorded on the magnetic tape is recorded, and an area 603A.
3A includes a re-recording area 603B for management data of the entire data recorded on the magnetic tape when the recording of 3A is defective.

The entire recording data is composed of unit data recording areas 605-1 to 605 -N, and a management data recording area (DIT) 606 is composed of these unit data recording areas 605.
-1 to N are management data recording areas dependent on each
This area is called T (Directry Information Table) area.
The IT area, as shown in detail in FIGS. 16A and B,
In the example shown in FIG. 16A, the recording area on the magnetic tape is divided in the longitudinal direction into DIT1 to DIT7, the number corresponding to the number of divisions (partition number) of the unit data recording area. Each of DIT1 to DIT7 is composed of a plurality of areas obtained by dividing the recording area on the magnetic tape in the longitudinal direction, as shown in FIG. 7B. ing.

The DIT divided as shown in FIG.
1 to DIT7, VIT (Volume Infor
mation table) area, each DIT area individually
Is recorded.

Then, of the management data shown in FIG.
The compression attribute (Compression type) of the entire recording data of the magnetic tape is recorded in the 4166 word (Word) area, and 819 of the management data shown in FIG.
Each unit data recording area 605 is stored in one word area.
Attribute corresponding to each of DIT to DIT7 (Compress
ion type) is recorded.

The management data shown in FIG. 18 and FIG.
Since the management data other than the 191 word area is data that is not directly related to the present example, it is only shown in these displays and the description is omitted, and the DI1 shown in FIG.
In the details of the data of DIT7 to DIT7, the regions other than the VIT region directly related to the present example are shown in FIG.

Next, an example in which the attribute added to the compressed data is recorded in the recording area of the ID code data for each sync block recorded on the magnetic tape will be described with reference to FIGS. 17 and 20. explain.

FIG. 17 shows a recording format of ID code data for each sync block in this example.
Of the ID code data recording formats
20 is a sub-code data area, and sub-code data shown in detail in FIG. 20 is recorded in the sub-code data area 701. Each sync block is stored in a 24-word area in FIG. Data indicating the attribute of each compression type (Compress type) is recorded.

Note that the data shown in FIG.
Since the data other than the 24-word (Word) area of 0 is data that is not directly related to the present example, it is only shown in each of these tables and the description thereof is omitted, and FIG. 17 does not directly relate to the present example. The region is shown in FIG. 17 and the description is omitted.

Therefore, in one example of the present invention described with reference to FIGS. 14 to 20, data representing the attribute of compressed data representing the entire magnetic tape is recorded in the VSIT area,
Data representing the attribute of each compressed data of each unit recording of the entire recording data is written in DIT1 to DI of each DIT area.
Data is recorded in T7 VIT areas and data representing the attribute of compressed data for each sync block is recorded in the subcode data area 701 in the ID code data for each sync block. .

Further, in one example of the present invention described with reference to FIGS. 14 to 20, the data representing the attribute of the compressed data representing the entire finished tape recorded in the VSIT area is set as default data, and In addition to recording at the time of initialization, data representing the attribute of the compressed data representing the entire magnetic tape and the compressed data of each individual unit record constituting the entire recording data recorded in each VIT area are recorded. The data representing the attribute and the subcode data area 70 in the ID code data for each sync block
A priority is given next to the data representing the attribute of the compressed data for each single block recorded in No. 1 in order to make the use of the data representing the attribute of the compressed data convenient.

That is, the data representing the attribute of the compressed data representing the entire magnetic tape recorded in the VSIT area is:
When the magnetic tape is formatted, the main system control unit 201 of the data recording / reproducing apparatus controls the recording in the VSIT area so that the default compression method of the tape is used.

With respect to the default compression method of the tape, data representing the compression attribute of each unit recording of the entire recording data is stored in each DIT area DIT1 to DIT7 of each DIT area of the magnetic tape. In the case of recording, the main system control unit 201 controls the memory control circuit 205 and the like so that the data representing the attribute recorded in the DIT area has priority over the compression method of the default value recorded in the VIIT area. ing.

Further, with respect to the data representing the attribute of the compressed data recorded in the VIT area, the subcode data area in the ID code data for each sync block of this tape, When the data representing the attribute of the compressed data for each sync block is recorded in the VIST area, the data representing the attribute of the compressed data recorded for each sync block is stored in the VIST area. The main system control unit 201 controls the memory control circuit 205 and the like so as to give priority to the data representing the compressed data attribute recorded in the VIT area.

Therefore, in this example, data representing the attribute of each compressed data of each unit recording of the entire recording data is not recorded in the VIT area, but is stored in the subcode data area 701 in the ID code data. Data indicating the attribute of the compressed data for each sync block may be recorded.

Alternatively, data representing the attribute of the compressed data may be recorded in the VIT area and not recorded in each sync block, and data representing the attribute of the compressed data may be recorded only in the VSIT area. It is needless to say that various changes can be made without deviating from the spirit of the present invention, such as not being recorded in the area and the subcode data area 701.

Next, details of the data recording / reproducing apparatus shown in FIG. 3 will be described with reference to FIGS. 21 and 22.

In FIG. 21, reference numeral 1 denotes the entire data recording / reproducing apparatus. As an example, the data recording / reproducing apparatus 1 includes a magnetic tape recording / reproducing section 100 and a magnetic tape recording / reproducing section 10.
0, a power supply unit 300 for supplying power to the data recording / reproducing apparatus 1, and a control panel 400 for operating the data recording / reproducing apparatus 1.

Then, the magnetic tape recording / reproducing unit 100
As an example, a magnetic tape recording / reproducing unit 10 composed of a rotating magnetic head type magnetic recording / reproducing device is shown.
0 denotes a rotation number signal of the rotating magnetic head device 101, a drive motor 102 for driving the rotating magnetic head device 101, a rotation head (not shown) of the rotating magnetic head device 101, and a rotation for detecting this rotation phase signal. Head sensor 103
A rotary head sensor output signal amplifier 104 that amplifies these two signals obtained from the rotary head sensor 103 to a predetermined signal level and supplies the amplified signal to the control unit 200 side, and a rotary head supplied from the magnetic tape control unit 200 side Rotating head (not shown) drive motor 1 by power-amplifying the drive signal
02 is provided with a drive amplifier 105 for driving the H.02.

Further, the magnetic tape recording / reproducing unit 10
0 denotes a control signal recording / reproducing head 106, a recording control signal amplifier 107 for amplifying a recording control signal supplied from the magnetic tape control unit 200 to a predetermined signal level and supplying the signal to the control signal recording / reproducing head 106; A control signal amplifier 108 that amplifies a reproduction control signal reproduced from the control signal recording / reproduction head 106 to a predetermined signal level and supplies the signal to the magnetic tape control unit 200 side, and recording data supplied from the magnetic tape control unit 200 side The signal is amplified to a predetermined signal level, and the recording heads 113A and 113 described later are amplified.
B, and amplifies a reproduction data signal reproduced from reproduction heads 114A and 114B to be described later to a predetermined signal level, and amplifies the reproduction data signal to a predetermined level.
And a reproduction signal amplifier 101P for supplying the reproduction signal amplifier 101P.

Next, an example of the rotary magnetic head device 101 will be described with reference to FIG.

The rotating magnetic head device 101 is provided with a rotating head drum 109, and the rotating head drum 109 is attached to the rotating head drum 109 at an angular interval of 180 degrees on the rotating peripheral surface thereof. Magnetic head units 110A and 110B are provided, and the rotating head drum 109 is supported by a rotating shaft 110C, and the rotating shaft 110C is rotatably supported by a mounting base (not shown).

The magnetic tape 111 is housed in a magnetic tape cassette 112, and both ends of the magnetic tape 111 are engaged with a take-up reel 112C and a supply reel 112D rotatably positioned in the magnetic tape cassette 112. The reel is wound around these reels in a stopped state.

The magnetic head unit 110A is disposed adjacent to the recording magnetic head 113A at a position following the magnetic head 113A when viewed in the rotation direction 110D of the rotary head drum 109. A twin head structure of a recording magnetic head comprising a reproducing magnetic head 114A and a reproducing magnetic head, and a magnetic head unit 110B is also provided with a recording magnetic head 113B.
When viewed in the rotation direction 110D of the rotating head drum 109, the recording magnetic head including the reproducing magnetic head 114B disposed close to the recording magnetic head 113B at a position following the recording magnetic head 113B and the reproducing magnetic head. It has a twin head structure with a magnetic head for use.

The recording magnetic heads 113A and 113A
Angle division interval with B and reproduction magnetic head 114A for reproduction
The angle division interval between the rotation head drum 114B and the rotation head 114B is set at an interval of 180 degrees, and is attached to the rotary head drum 109.

When recording and reproducing data signals by the rotary magnetic head device 101, the magnetic tape 111 is moved by the first tape pull-out guide pins 112A into the take-up reel 112C and the supply reel 11 in the magnetic tape cassette 112.
2D after being pulled out from a position stretched between the 2D and a predetermined position outside the magnetic tape cassette 112,
Is wound clockwise over a predetermined range of the rotary head drum 109 by the tape pull-out guide pin 112B, and the tape is loaded.

During recording on the magnetic tape 111, in this tape loading state, the magnetic tape 111 is transferred at a predetermined speed by a tape transfer mechanism (not shown) such as a capstan, and the servo control unit 203 In the recording servo state, the recording signal from the recording signal amplifier 101R is supplied to the recording heads 113A and 113B so that the recording is performed at a predetermined position on the magnetic tape 111 and the servo control unit 203 is controlled.
Generates a control signal indicating the recording position of the recording track, and transfers this signal to the control signal recording / reproducing head 1.
06 is recorded in a well-known configuration.

When the magnetic tape 111 is reproduced, in the tape loading state, the servo control unit 203 performs a reproduction servo state based on the control signal reproduced by the control signal recording / reproduction head 106.
While transferring the magnetic tape 111 at a predetermined speed by a tape transfer mechanism (not shown) such as a capstan, the reproducing head 1
A well-known reproduction data signal obtained by reproducing this recording track with the recording tracks 14A and 114B racked to this recording track is amplified to a predetermined signal level by a reproduction signal amplifier 101P and supplied to the magnetic tape control unit 200 side. It has a configuration.

In FIG. 21, the magnetic tape control unit 200
Are a main system control circuit 201, a magnetic tape running control circuit 202, a servo control circuit 203, a data compression / decompression circuit 204, a memory control circuit 205, a main memory circuit 20
6, outer code parity adding circuit 207, inner code parity adding circuit 208, 8-9 bit converter 209, precoder 210, Viterbi decoder 211, 9-8 bit converter 21
2. Inner code parity corrector 213, outer code parity corrector 214, SCSI (SCSI: Small Computer Intefa)
ce) Interface 215, SCSI connector 21
6, an RS-232C connector 217 and an optional connector 218.

The encoder 230 is composed of the outer code parity adding circuit 207, the inner code parity adding circuit 208 and the 8-9 bit converter 209.
2. The decoder 240 is composed of the inner code parity corrector 213 and the outer code parity corrector 214.

The RS-232 connector 217 is a connector for connecting to an external data terminal (not shown) according to the well-known RS-232C standard, and the optional connector 218 is a well-known equipment (not shown) treated as other options.
A power supply unit 300 is a power supply for supplying power to the magnetic tape control unit 200, and a control panel 4
Reference numeral 00 denotes a control panel of the magnetic tape control unit 200. On the control panel 400, display members such as lamps and LEDs indicating the operation state of the main system control circuit 201 are provided with switches for operating the main system control circuit 201 with good operability. It is a well-known control panel provided.

Among the devices constituting the magnetic tape control section 200, the magnetic tape running control circuit 202, the servo control circuit 203, the data compression / expansion circuit 204, the memory control circuit 205, the SCSII / F 215, and the control panel 400 are internally controlled. They are connected so that they can mutually transmit and receive control signals via a bus 219.

The main system control circuit 201 instructs the tape running control circuit 202 through the internal control bus 219 to control the tape running state of the magnetic tape recording / reproducing unit 100, and instructs the data compression / expansion circuit 204. It controls the compression and decompression of the data signal obtained from the memory control circuit 205 and the SCSI interface 215, instructs the memory control circuit 205 to control the writing and reading of data to and from the main memory circuit 206, and instructs the SCSI interface 215. It has a function of controlling reading of data from the common bus 216A and sending of data to the common bus 216A.

The tape running control circuit 202 has a function of instructing the servo control circuit 203 through the internal control bus 219 based on the instruction from the main system control circuit 201 to execute the recording servo and the reproduction servo described above. In addition, the main system control circuit 201 itself has a function of performing recording, reproduction, fast-forward and rewind operations, or tape pre-roll operation of the magnetic tape.

The servo control circuit 203 has the function of executing the recording servo and the reproduction servo described above, and the rotation speed and the rotation phase of the capstan drive motor (not shown) in accordance with the recording servo and the reproduction servo. , And a function of servoing the rotation direction and the number of rotations of the reel motors 112C and 112D (not shown).

The tape pre-roll operation is performed by, for example, a well-known method that is used when a new signal is recorded by connecting to a recorded portion already recorded on the magnetic tape 111. After returning the magnetic tape a little, stop the tape and set a tape running section before this new recording point.During this section, the running speed of the magnetic tape reaches the specified value and the servo of the rotary head etc. Operation to lock the tape, or stop the tape at the end of the already recorded recording, and when performing the next recording, start the tape from this stopped position in the recording servo state. In this operation, the traveling speed of the motor reaches the specified value and the servo of the rotary head and the like is locked.

In order to start recording from this pre-roll state, when the servo control circuit 203 detects that the recording servo is locked, the main system control circuit 201 instructs the memory control circuit 205 to The reading of data from the circuit 206 is started, and the next recording on the magnetic tape 111 is started.

In addition to the case other than recording, when reproduction is started from a specific place on the magnetic tape 111 during reproduction,
This pre-roll operation is used.

Next, referring to FIG. 21, a mode for prohibiting the application of compression described with reference to FIG.
A description will be given of the signal processing until the data of the SCSI format taken into the SCSI interface 215 via the SCSI connector 216 is recorded on the magnetic tape 111 as a predetermined recording track.

The data of the SCSI format transferred from the common bus 216A to the SCSI interface 215 is converted into a predetermined format of the data recording / reproducing apparatus, and the data is transmitted from the SCSI interface 215 to the data compression / expansion circuit 204 to the predetermined data recording / reproducing apparatus. Format data is supplied.

In this case, since the discrimination data 00h prohibiting the application of the compression is transferred at the same time, the main system control circuit 201 determines from the discrimination data that the data compression is unnecessary, and the main system control circuit 201 The data compression / expansion circuit 204 is controlled from the main system control circuit 201 based on the judgment, and the supplied format data of the data recording / reproducing device is passed through the compression / expansion device 204 to maintain the compressed state, and this data is passed through. The predetermined format data of the data recording / reproducing apparatus is supplied to the memory control circuit 205, and the memory control circuit 205 is controlled to write the predetermined format data of the data recording / reproducing apparatus to the main memory circuit 206.

The main system control circuit 201 controls the memory control circuit 205 so that when the amount of format data of the data recording / reproducing device written in the main memory circuit 206 reaches a predetermined amount, for example, one sync block length. The additional data necessary for the data of one sync block length, for example, peripheral data such as a sync, an ID, and a subcode are added from the memory control circuit 205 to the main memory circuit 2.
06.

Next, the main system control circuit 201 instructs the tape running control circuit 202 and the servo control circuit 203 to execute the pro-reel operation and subsequently the recording servo lock operation to confirm that the recording servo is locked. .

When this confirmation is obtained, the main system control circuit 201 controls the memory control circuit 205, and the main memory circuit 206 adds the peripheral data to the data recording / reproducing apparatus and formats the data into a magnetic tape recording / reproducing unit. The data is converted into 8-bit data series data of the format and read, and the 8-bit data series data of the magnetic tape recording / reproducing unit format is supplied to the outer code parity adding circuit 207.

The outer code parity adding circuit 207 adds an error correcting outer code parity to the supplied 8-bit data series data of the magnetic tape recording / reproducing unit format, and then supplies the data to the inner code adding circuit 208.

The inner code parity adding circuit 208 adds an error correcting inner code parity to the 8-bit data sequence data of the magnetic tape recording / reproducing unit format to which the outer code parity has been added, and then adds 8-9 bits. It is supplied to the converter 209.

The 8-9-bit converter 209 converts the 8-bit data sequence data of the magnetic tape recording / reproducing unit format to which the code and the inner code parity are added into 9-bit data sequence data in which the DC component of the data is minimized. After that, it is supplied to the precoder 210.

The precoder 210 converts the 9-bit data series data into, for example, interleaved NRZI data to generate a recording data signal for the purpose of facilitating clock reproduction during reproduction, and records the recording data. The signal is supplied to the signal amplifier 101R.

The recording signal amplifier 101R amplifies the supplied recording data signal to a predetermined signal level and supplies the signal to the recording heads 113A and 113B.

With the servo control circuit 203 operating the recording servo, the recording heads 113A and 113B
Then, this recording data signal is recorded as a predetermined recording track on the magnetic tape 111 running at a predetermined speed.

Next, referring to FIG. 21, a mode in which the application of compression described in FIG. 10 is prohibited will be taken as an example, and until a recording data signal obtained by reproducing this recording track from the reproducing heads 114A and 114B is transferred to the common bus 216A. Will be described.

The main system control circuit 201 instructs the tape running control circuit 202 and the servo control circuit 203 to
A pre-roll operation and subsequent reproduction servo lock operation are executed, and it is confirmed that the reproduction servo is locked and the reproduction tracking of the reproduction heads 114A and 114B with respect to the recording track is achieved.

When the confirmation has been made, the main system control circuit 201 instructs the tape running control circuit 202 to read the recording heads 114A and 114B from the recording tracking.
Then, the recording data signal is reproduced, and the reproduced recording data signal is amplified to a predetermined signal level by the reproduction signal amplifier 101P.
Feed to 1.

The Viterbi decoder 211 supplied with the reproduced data signal decodes the interleaved NRZI reproduced data into 9-bit data series reproduced data, and converts the 9-bit data series data to 9-8 data. This is supplied to the bit converter 212.

The 9-8-bit converter 212, which has been supplied with the data of the 9-bit data series, decodes the reproduced data signal of the 9-bit data series into the original 8-bit data series, and The series data signal is supplied to the inner code parity corrector 213.

The inner code parity corrector 214, which has been supplied with the reproduced data signal of the 8-bit data series, performs error correction using the inner code parity data, and performs error correction using the inner code parity data. The reproduced data signal of the 8-bit data series is converted into an outer code parity corrector 2
14.

The outer code parity corrector 214, which has been supplied with the reproduced data signal of the 8-bit data series for which error correction has been performed using the inner code parity data, performs error correction using the outer code parity data, and And a sync block length format 8-bit data sequence data signal, which is the original magnetic tape recording / playback format data signal, is obtained from the memory. It is supplied to the control circuit 205.

The memory control circuit 205 which has been supplied with the sync block length format 8-bit data series reproduced data signal from the outer code parity corrector 214 supplies the sync block length format 8-bit data sequence reproduced data signal. Is read into the main memory circuit 206.

The main system control circuit 201 controls the memory control circuit 205 so that the reproduced data signal of the original sync block length format 8-bit data series written in the main memory circuit 206 can be transmitted to the data recording / reproducing apparatus at a predetermined level. The data is read after being converted into the format data, and whether or not the read data is compressed is confirmed from the data representing the compression attribute of the read data.

If it is confirmed that the data is compressed, the main system control circuit 201 reads the data of a predetermined format read from the main memory circuit 206 into the data recording / reproducing device. The data is supplied to the data compression / expansion circuit 204, and the data compression / expansion circuit 204 decompresses the supplied data in a predetermined format of the data recording / reproducing apparatus, and then executes S
Instruct CSII / F215 to supply.

However, when it is confirmed that the data is not compressed as a result of the confirmation, the main system control circuit 201 transmits the data of a predetermined format read from the main memory circuit 206 to the data recording / reproducing apparatus. The data is supplied to the data compression / expansion circuit 204, and the supplied data of the predetermined format is passed through the data recording / reproduction device 204 without compressing / expanding the data, and then supplied to the SCSII / F 215. To instruct.

Therefore, if it is confirmed from the data representing the compression attribute of the read data that the read data is not compressed, the data compression / decompression circuit 20
In accordance with an instruction from the main system control circuit 201, the data recording / reproducing apparatus 4 passes through the supplied data in a predetermined format without compressing / expanding, and confirms that the read data is compressed. In this case, the supplied data in the predetermined format of the data recording / reproducing device is expanded, and the data in the predetermined format of the data recording / reproducing device is transferred to the SCSII / F215.
To supply.

The SCSI II / F 215 converts the data of the predetermined format supplied from the data compression / expansion circuit 204 into the SCSI format, and converts the data converted into the SCSI format into the common bus 216A. Through to the host computer 500.

In the example described above, an example in which two or three sets of data recording / reproducing devices are used has been described. However, the number of data recording / reproducing devices is limited to two or three in this example. It is needless to say that the present invention can be applied to an example in which four or more sets are used, and the data recording / reproducing apparatus is not limited to the rotary magnetic head type recording / reproducing apparatus, Of course, it can be used for various types of signal recording / reproducing media such as a signal recording / reproducing device or a data recording / reproducing device using a desk-type recording medium.

In the example described above, data recorded / reproduced by the magnetic tape recording / reproducing unit has been described as an example. However, other than this, data used in the data recording / reproducing apparatus such as management information data, log data, and self-diagnosis data. Of course, the present invention can be applied to various types of data such as downloaded data, firmware download of a data recording / reproducing device, uploading and downloading of management information of a magnetic tape, and the like.

In the example described above, the compression / expansion operation of the data compression / expansion circuit 204 is performed by inputting / outputting the input data to / from the data compression / expansion circuit 204 without performing any compression or expansion. Although the operation has been described as an operation, the data compression / expansion circuit 2
04, the memory control circuit 205 and the main memory circuit 20
6, the operation of expanding the input compressed data once, performing necessary processing on the expanded data, recompressing and outputting the required processing, and the case where the input data is compressed. The operation of changing the compression algorithm of this input data and outputting it, for example, when the input data is J
If the data is compressed by the PEG algorithm, the operation of converting the data to data compressed by the MPEG algorithm and outputting the data is, of course, included in the compression operation.

In the example described above, in the data recording / reproducing apparatuses 1A and 1B having the function of transferring data, which are the data recording / reproducing apparatus of the data transfer source and the data recording / reproducing apparatus of the data transfer destination, 500
And a means for connecting to a data transfer means comprising a common bus 216A to determine a signal compression / expansion mode to be transferred between a data transfer source and a data transfer destination; and a main system control circuit 201 and a data compression / expansion circuit 204. A means for processing data transferred in the decompression mode is provided in the data recording / reproducing apparatus serving as the data transfer source, so that the data to be transferred can be transferred in accordance with the signal compression / decompression function of the data transfer destination. Since the transfer can be performed in the signal compression mode, the transfer speed can be improved.

In the example described above, the data recording / reproducing apparatus 1A, 1B having the function of transferring data, which is the data recording / reproducing apparatus of the data transfer source and the data recording / reproducing apparatus of the data transfer destination, has a common bus. A main system control circuit 201 connected to a data transfer unit 216A to determine a signal compression / decompression mode to be transferred between the data transfer source and the data transfer destination based on copy command information obtained through the transfer unit; And a means for processing data to be transferred in the signal compression / expansion mode, comprising the data compression / expansion circuit 204, is provided in the data transfer / reproducing apparatus of the data transfer source. The transfer speed can be improved because it is possible to transfer in the signal compression mode. Door is possible.

In the example described above, in the data recording / reproducing apparatuses 1A and 1B having the function of transferring data, which are the data recording / reproducing apparatus of the data transfer source and the data recording / reproducing apparatus of the data transfer destination. Transfer destination or host computer 500 connected to this data transfer destination
From the SCSII / F 215 and the main system control circuit 201 for obtaining the data compression / decompression function information of this data transfer destination via the data transfer means comprising the common bus 216A, and the transfer source via the common bus 216A. The main system control circuit 201 and the data compression / expansion circuit 204 process the data to be transferred from the data transfer destination to this transfer destination within the range of this function obtained based on the data compression / decompression function information of this data transfer destination from this data transfer destination. By means of
Since the data to be transferred can be transferred according to the signal compression / decompression function of the data transfer destination, the data can be transferred particularly in the signal compression mode, and the transfer speed can be improved.

In the example described above, in the data recording / reproducing apparatus 1C having the function of transferring data, the data transferred from the data recording / reproducing apparatuses 1A and 1B of the data transfer source via the common bus 216A is transferred. From the data recording / reproducing apparatuses 1B and 1A, the common bus 216A
The main system control circuit 201 and the data compression / decompression circuit 2 in accordance with a compression / decompression instruction by a copy command obtained through
04 and the SCS is sent to this data transfer destination.
Since the data is transferred via the II / F 215 and the common bus 216A, only the data compression / decompression function of the data recording / reproducing apparatus 1C is used for the data recording / reproducing apparatus 1C connected to the data recording / reproducing apparatus 1C via the common bus 216A. It can be used as a data compression / decompression function of a playback device,
It becomes possible to incorporate a data recording / reproducing apparatus having little data compression / decompression function or no data compression / decompression function into this network.

In the example described above, in the data recording / reproducing apparatuses 1A and 1B having the data transfer function, the transferred data is converted into a signal from the data recording / reproducing apparatus 1A or a data transfer source such as the host computer 500. Processing is performed in accordance with the instruction of the compression / expansion mode, and the data is written to the data recording apparatus of the transfer destination. Therefore, the signal compression / expansion mode of the data recording / reproduction apparatus of the data transfer destination can be set from the data recording / reproduction apparatus of the data transfer source. Therefore, even when the data recording / reproducing apparatus at the data transfer destination is located at a location remote from the data transfer source, the signal compression / decompression mode of the data recording / reproducing apparatus at the data transfer destination is varied from the data transfer source. Can be set to improve usability.

In the example described above, the common bus 21
The data compression / decompression of the data recording / reproducing apparatus of the data transfer destination is performed by a data recording / reproducing apparatus serving as a data transfer source or a data recording / reproducing apparatus serving as a data transfer destination via a common bus via a common bus 6A. Since a means for transmitting the mode information to the data recording / reproducing apparatus serving as the data transfer source is provided, the compression / decompression mode of the data transferred from the data recording / reproducing apparatus of the transfer source is set as follows.
Since data can be processed and transferred to the data transfer destination within the range of the data compression / decompression mode obtained from the data transfer / reproduction device as the data transfer destination, for example, the data recording / reproduction device as the data transfer source Even when a data recording / reproducing apparatus having a smaller number of data compression / expansion modes than the number of data compression / expansion modes is used as the transfer destination, it is possible to transfer the compressed / expanded data, and to record a plurality of data via the common bus 216A. Restrictions on the transfer of compressed / decompressed data when forming a network with the playback device are reduced.

In the example described above, in a data recording / reproducing apparatus having a function of transferring data, data transferred from a data transfer source other than the data recording / reproducing apparatus is subjected to compression / expansion processing, and the data By providing a means for transferring data to a data transfer destination other than the reproducing apparatus, only the data compression / expansion function of the data recording / reproducing apparatus can be used as the data compression / expansion function of the data recording / reproducing apparatus other than the data recording / reproducing apparatus. This makes it possible to incorporate a data recording / reproducing apparatus having a small data compression / decompression function or no data compression / decompression function into this network, thereby reducing the restrictions on forming the network.

[0276]

According to the present invention, the setting of the compression / decompression mode at the time of data transfer can be performed in the data compression mode in addition to the data decompression mode, so that the setting can be made according to the data compression function of the data transfer destination. In particular, the data can be transferred in the data compression mode, and the data transfer speed can be improved.

[Brief description of the drawings]

FIG. 1 is a block diagram for explaining an example of a basic configuration of a data transfer net.

FIG. 2 is a block diagram for explaining another example of the basic configuration of the data transfer net;

FIG. 3 is a block diagram for explaining an example of a configuration of a main part of the data recording / reproducing apparatus.

FIG. 4 is a block diagram for explaining a signal flow according to the present invention when data is recorded without being compressed and expanded.

FIG. 5 is a block diagram for explaining a signal flow according to the present invention when the reproduced data is expanded and transferred.

FIG. 6 is a block diagram for explaining a signal flow according to the present invention when transferring reproduced data without compressing / decompressing the data.

FIG. 7 is a block diagram for explaining an example of a signal flow according to the present invention when data is compressed and recorded.

FIG. 8 is a block diagram for explaining an example of a signal flow according to the present invention when a compression / expansion circuit of the data recording / reproducing apparatus is used.

FIG. 9 is a flowchart for explaining an example of a judgment by the system control circuit according to the present invention;

FIG. 10 is a flowchart illustrating an example of a determination according to the present invention in a mode in which application of compression is prohibited.

FIG. 11 shows a mode of a device default compression mode.
6 is a flowchart for explaining an example of a determination according to the present invention.

FIG. 12 is a flowchart illustrating an example of a determination according to the present invention in a through mode.

FIG. 13 is a flowchart illustrating an example of a determination according to the present invention in a compression / expansion mode.

FIG. 14 is a flowchart for explaining an example of the determination according to the present invention of the data array at the leading end of the magnetic tape.

FIG. 15 is a diagram provided for describing an example of a data array of the entire magnetic tape.

FIG. 16 is a diagram provided for describing an example of a data array of a DIT area.

FIG. 17 is a diagram provided for describing an example of a subcode data array.

FIG. 18 is a diagram provided for describing an example of a management code data array.

FIG. 19 is a diagram provided for describing an example of a unit management code data array.

FIG. 20 is a diagram provided for describing an example of a subcode management data array.

FIG. 21 is a block diagram for describing an example of details of a data recording / reproducing device.

FIG. 22 is a block diagram for explaining an example of a rotary magnetic head device.

[Explanation of symbols]

1A, 1B data recording / reproducing device, 100 magnetic tape recording / reproducing unit, 201 main system control circuit, 204 data compression / expansion circuit, 205 memory control circuit, 206
Main memory circuit, 215 SCSII / F, 216 common bus, 500 host computer

Claims (3)

[Claims] 1. A data recording / reproducing apparatus having a data transfer function, comprising: means for determining a signal compression / expansion mode for transferring data between a data transfer source and a data transfer destination; A data recording / reproducing apparatus provided with processing means. 2. A data recording / reproducing apparatus having a data transfer function, comprising: means for obtaining data compression / decompression function information of a data transfer / reproduction apparatus of a data transfer destination; Means for processing and transferring data within a range of a data compression / decompression function obtained based on the data compression / decompression function information from a data transfer destination. 3. A data recording / reproducing apparatus having a function of transferring data, processes data transferred from a data transfer source according to a compression / decompression instruction from a data transfer destination, and
A data recording / reproducing apparatus provided with means for transferring data to a data transfer destination.