JPS593667A - Data transfer system between magnetic tape and magnetic disk - Google Patents

Abstract

PURPOSE:To perform data transfer in a short time without the intervention of a CPU by providing at least two buffer devices between a block type magnetic tape device and a sector type magnetic disk device. CONSTITUTION:The magnetic tape device 1 and magnetic disk device 5 are connected mutually by data transfer paths 2 and 4 through a data transfer controller 3. The data transfer controller 3 consists of a magnetic tape buffer device BMF 7 and a magnetic disk buffer device BFD 8 which are controlled by a microprocessor MPU 6. For example, when data transfer mode from the tape device 1 to the disk device 5 is set under the control of the MPU 6, one-block data from the tape device 1 is stored in the memory in the BMF 7, and the BFD 8 is placed in data receiving mode to store the data in the memory. Then, the data from the BFD 8 is written in free sectors of the disk 5. Reverse transfer is the same. Thus, the data transfer time is shortened.

Description

Detailed Description of the Invention (1) Technical Field of the Invention The present invention relates to an improved data transfer means between a magnetic disk device and a magnetic tape device [7] and relates to a data transfer method between magnetic disks and magnetic tapes. .

(2) Background of the Technology Conventionally, magnetic disk devices and magnetic tape devices have been used as external storage devices for information processing devices. These external storage devices not only exchange data with the internal storage device of the information processing device, but also need to transfer data between these external storage devices. Problems such as the long time it takes to transfer formalities data have arisen, and there is a need for the development of technical means that can solve these problems.

(3) Prior Art and Problems When transferring data between a conventional magnetic tape device and a magnetic disk device, the data in the magnetic tape device or magnetic disk device is first stored in the internal storage device of the central processing unit and then transferred. Since data is transferred to a magnetic disk device or a magnetic tape device, the data transfer time is unavoidably long, and the magnetic tape device must be started and stopped repeatedly.

(4) 6 Purpose of the Invention The present invention was devised in view of the drawbacks of the conventional system as described above, and its purpose is to connect a magnetic disk device and a magnetic tape device without going through the internal storage device of the central processing unit. An object of the present invention is to provide a data transfer method between a magnetic disk and a magnetic tape, which allows data transfer between a magnetic disk and a magnetic tape.

(5) Structure of the Invention This object is achieved by providing at least two buffer devices in a data transfer control device between a magnetic disk device and a magnetic tape device, and causing data transfer to occur via these buffer devices. be done.

(6) Embodiments of the Invention The present invention will now be described in detail with reference to the accompanying drawings.

FIG. 1 shows the configuration of an apparatus for implementing the present invention.

In this figure, reference numeral 1 denotes a magnetic tape device, which is connected to a magnetic disk device 5 via a data transfer path 2, a data transfer control device 3, and a data transfer path 4. The magnetic tape device 1 and the magnetic disk device 5 are, for example, of a block format type and a sector format type, respectively.

The data transfer control device 3 is a microprocessor unit (
Hereinafter, it will be referred to as MPU. ) 6, a magnetic tape buffer device (hereinafter referred to as BF, M) 7, and a magnetic disk buffer device (hereinafter referred to as BF, D) 8, and BF, M7, BF, D8 are also It is placed under the control of MPU 6, and also D)Gl, G2 . G3゜G4.
G5 is also placed under the control of MPU6.

Details of BF, M7 and BF, D8 are shown in FIG. BF and M7 as well as BF and D8 each consist of buffer memories 9M and 9D, a direct memory access control unit (hereinafter abbreviated as DMAC) IOM, IOD, and registers IIM and IID. Register 11M, I
For each ID, a control signal is set under the control of the MPU 6 to start up the corresponding DMA010M and IOD, and also to supply a gate signal to the D/G2. The DMAC 10M is used to control data transfer between the magnetic tape device 1 and the buffer memory 9M, and between the buffer memory 9M and the buffer memory 9M and the buffer memory 79D via the DMAC 10Din. Also, DMACl0
D is for controlling data transfer between the buffer memory 9D and the magnetic disk device 5.

Next, the operation of the above-mentioned component devices will be described in the case where the magnetic tape device is of the block format type and the magnetic disk device is of the sector format type.

First, data transfer from the magnetic tape device 1 to the magnetic disk device 5 will be explained.

When the control of the MPU 6 enters this operation mode, a control signal is set from the MPU 6 to the register IIM, and then the DMA
C10M is activated. Then, DMAC10M
Under the control of the magnetic tape device 1, if there is space for one data block or more in the buffer memory 9M, one data block is transferred from the magnetic tape device 1 to the buffer memory 179M.This transfer is relatively slow. This is done within a short time interval tt (see Figure 3).

Due to the nature of block format magnetic tape devices,
An empty time of VCt2 occurs until the next block N is read.

During this free time, if BF and M7 have the amount of data that can be transferred, and if BF and DB have free storage capacity that can accommodate the amount of data, MP
Under the control of U6, KDMACIOM, 10D and registers 11M, IID operate in the following manner: B F, M
Data transfer control is switched from 7 to BF and DB.

As a result, data is transferred from BF, M7 to BF, DB. After this data transfer between the sofa devices, if the amount of data that can be transferred to the magnetic disk device is stored in BF and DB,
Under the control of MPU6, nMAcloD, register 11
The operation mode D is switched to the writing mode of BF, data from D8 to the magnetic disk device 5, and data is written to the magnetic disk device 5.

These operations will occur if the respective conditions are not met.
Data transfer from BF, M7 to BF, DB,
Also, no data is written from the BF, DB to the magnetic disk device 5. Moreover, these operations are caused independently of each other.

In this way, the required number of data blocks read from the magnetic tape device 1 are temporarily stored one after another in BF, M7, and then transferred to BF.

The data is transferred to the DB, and from the DB to the magnetic disk device 5, it can be transferred without starting or stopping the magnetic tape device 1.

Further, data transfer from the magnetic disk device 5 to the magnetic tape device 1 is performed in the reverse order to that described above.

That is, when transferring data from the magnetic disk device 5 to the magnetic tape device 1, the magnetic tape device 1 is transferred to BF, M7.
The following operations occur until the amount of data required to be transferred to, for example, one data block or more is present.

There is enough data in B F, DB to transfer from there to B F, M7, and DMACl0 responds to it.
D, IOM and register 11D.

After transferring the amount of data that can be transferred from BF and DB to BF and M7 with the cooperation of 11M, BF.

The amount of data that can be transferred from the magnetic disk device 5 to the DB is transferred under the control of the DMAC 10D that responds to the register IID.

As a result of the data transfer from BF, D8 to BF, M7, when there is enough data in BF, M7 to be transferred to the magnetic tape device, for example, one data block or more, the register 11M is transferred.

A write operation is performed from BF and M7 to the magnetic tape device 1 under the control of the DMAC 10M. In this case as well, the transfer to the magnetic tape device 1 is performed within tl, as shown in FIG. Therefore, it takes time t2 before the next data block can be received.

Within this time, after the transfer to the magnetic tape device 1, a free storage area of the amount of data that can be transferred is created in BF, M7, and BF.

If the DB stores enough data to enable data transfer to BF and M7, BF.

Data transfer occurs from DB to BF, M7. Also, after data transfer between the buffer devices, BF, D
If a free storage area large enough to transfer data from the magnetic disk device 5 occurs in B, the data read from the magnetic disk device 5 is stored in that storage area.

Each of these operations is sequentially stored from the magnetic disk device 5 to BF and DB, and from there to BF and M7, until the data block required by the magnetic tape device is transferred from the magnetic disk device 5. Transferred to B F.

Data can be transferred from M7 to the magnetic tape device 1 without causing the magnetic tape device to start or stop.

As described above, according to the present invention, direct data transfer between a magnetic tape device and a magnetic disk device is possible simply through the buffer device, so that the internal storage device of the central processing unit, which is conventional, can be transferred. Compared to data transfer via
Data transfer time can be significantly reduced. Furthermore, there is no need to start or stop the magnetic tape device, contributing to a reduction in data transfer time. Furthermore, it greatly contributes to reducing the burden on the control ability of the central processing unit.

In the above embodiment, an example in which two buffer devices are provided has been described, but the present invention is not limited to this.

(7) Eight Effects of the Invention As described above, according to the present invention: (1) The data transfer time between the magnetic tape device and the magnetic disk device can be shortened.

■ There is no need to repeatedly start and stop the magnetic tape device.

■ Effects such as contributing to a reduction in the control burden on the central processing unit can be obtained.

[Brief explanation of the drawing]

FIG. 1 is a block diagram of one embodiment of the present invention, and FIG. 2 is a block diagram of an embodiment of the present invention.
FIG. 3 is a detailed view of the main parts of the apparatus, and FIG. 3 is a diagram showing the timing relationship of the present invention without further explanation. In the figure, 1 is a magnetic tape device, 5 is a magnetic disk device, and 3 is a magnetic tape device.
is a data transfer control device, and 7.8 is a buffer device.

Claims (1)

[Claims] fl) A data transfer control device between a magnetic tape device and a magnetic disk device is provided with at least two sofa devices, and data transfer occurs via these sofa devices. A data transfer method between a magnetic tape and a magnetic disk. (2) The magnetic tape device is of a block format type, and the magnetic disk device is of a sector format type. A magnetic tape-magnetic disk data transfer method according to scope 1, (3) the buffer device is coated with a gold film on the magnetic tape device and the magnetic disk device, and the buffer device is provided with a gold film on the magnetic tape device and the magnetic disk device, A magnetic tape-magnetic disk data transfer method according to claim 2, characterized in that data transfer occurs between devices and between the buffer device and the magnetic disk device;