JPS6273355A - Data processing system - Google Patents

Abstract

PURPOSE:To lighten a load at a computer side by installing an I/O server between a LAN to which a computer is connected and an I/O device and exchanging data by the I/O device through the I/O server and an auxiliary external storage device. CONSTITUTION:The personal computers 1a-1n have a local area circuit network LAN interface 2, and designate the I/O server 3 on an I/O action. Assuming that the I/O action is a data input from an FD device (floppy disk) 4C, the input data from the device 4c is provisionally stored in the external storage device, that is, a magnetic tape device 6a, for instance, by means of the server 3. After the storage of data, the server 3 acts according to a command from the computer 1a, and transmits the input data stored in the device 6a to the computer 1a through the LAN 2. Thus the I/O interface of the computer is simplified, and the load at the computer side can be lightened accordingly.

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field of the Invention] The present invention relates to a data processing system that processes data using a computer and peripheral devices attached thereto.

[Technical background and problems of the invention]

Various 1/O devices such as printers, plotters, and magnetic tape devices are connected to computers such as personal computers. Various interfaces are used depending on the type of I/O device. For example, printers generally use Centronics, modems, and other communications equipment such as R.
8-232G is 4! However, for high-speed equipment such as magnetic disk drives, special interface devices are used. Therefore, computers have the disadvantage that they must be equipped with functions corresponding to these various interfaces.

Furthermore, since software is required to control each I/O device at time 11, there is a drawback that the load on the CPU of the computer increases. Although there is a method of providing a CPU for each I/O device to reduce the load on the computer, this method requires a large number of CPUs, leading to an increase in cost.

Furthermore, the cable that connects the computer and the I/O device is
Since the cable is required for each /O device, it has the disadvantage that the cable occupies too much space depending on the system configuration.

[Purpose of the invention]

The present invention has been made to overcome the above-mentioned drawbacks of the prior art, and it is an object of the present invention to provide a data processing system that can simplify the F/O interface and reduce the burden on the computer.

(Summary of the invention) In order to achieve the above object, the present invention provides
An I/O server is used to intervene when connecting a 1/O device to an AN (local area network), and this I/O
The computer operates according to commands from the computer.
When data output processing is specified, data from the computer is stored in an external storage device and then output from the specified I/O device, and when data input processing is specified, it is output from the specified I/O device. The present invention provides a data processing system in which input data is once stored in an external storage device and then sent to a computer via a LAN.

(Embodiment of the Invention) Hereinafter, an embodiment of the present invention will be described with reference to the accompanying drawings.

FIG. 1 shows the configuration of the same embodiment. A plurality of personal computers 1a to 1n are connected to each other via a LAN (Local Area Network) 2, and the LAN 2 includes a
1/O equipment is connected via the O server 3. I/
The O+a devices include a printer 4a, a plotter 4b, a floppy disk device 4C, etc., and each of these has an I/O
It is connected to the I/O server 3 via interfaces 5a to 5C. I/O interfaces 5a to 5C
are known, such as R8-23201 Centronics and GP-IB. Also, I/O server 3
The i! magnetic tape device is used as an external storage device. Y6a and magnetic disk device 6b are connected via interfaces 7a and 7b.

FIG. 2 shows the format of a communication packet from a computer to an I/O server. This packet must send all bit patterns, so the HD
An LC-like format is desirable. As shown in Figure 2, the packet is I/O! which indicates the actual 1/O device.
11 device address 8, command C to I/O server 3, input/output data■, and error check code FC8
It consists of

Next, the operation will be explained. Computers 18 to 1n are LAN
It has only an interface, and is connected to the I/O server 3.
/O Request action. That is, the computer that has generated the I/O request (for example, computer Ia) first performs the I/O request.
Sends a command to the O server 3 and sends the command I/Ofl! l
Specify. When the 1/O device is specified by the computer 1a, the I/O server 3
The device's control program is activated, thereby preparing for data input/output.

When the specified I/O operation is, for example, data output to the printer 4a, the output data from the computer 1a is temporarily stored in an external storage device (for example, magnetic disk drive M6b) by the I/O server 3, and then the data is stored. When this ends, data transmission on LAN2 ends. after that,
The I/O server 3 independently performs output according to command C from the computer 1a. That is, the output data stored in the magnetic disk device a16b is read and output to the printer 4a.

The specified I/O operation is, for example, a floppy disk drive.
When data is input from the floppy disk 8tff4C, the input data from the floppy disk 8tff4C is stored in an external storage device, for example, a magnetic tape device 6a, by the I/O server 3.
). This data storage is performed according to commands from the computer 1a, but no data is transmitted over the LAN 2 during this time. After storing the data, the I/O server 3 operates according to commands from the computer 1a,
The input data stored in the magnetic tape device 6a is
N2 to the computer 1a.

The invention is not limited to the above embodiments.

For example, the LAN is not limited to a bus type, but may be a loop type or a star type. Furthermore, the I/O 111 and external storage device are not limited to those of the embodiment.

〔Effect of the invention〕

As described above, in the present invention, the LAN to which the computer is connected
An I/O server is installed between the I/O device 0 and the I/O device 0, and data input/output by the 1/O 1 device is performed via the I/O server and the external storage device attached to it. One I/O interface! ! ! This provides a data processing system that can reduce the burden on the computer.

[Brief explanation of drawings]

FIG. 1 is a block diagram of an embodiment of the present invention, and FIG. 2 is a format diagram of a communication packet used in the embodiment. 2...LAN (local area network), 5
a to 5c, 7a to 7b...interface.

Claims (1)

[Claims] A LAN, an I/O server connected to this LAN, and an I/O connected to the LAN via this I/O server.
device, an external storage device connected to the LAN via the I/O server, and the I/O device connected to the LAN and executing I/O processing, and the specified I/O a computer that sends a command specifying processing content of the O device to the I/O server via the LAN, the I/O server operates according to the command from the computer, and data output processing is specified. When data from the computer is stored in the external storage device, it is output from the specified I/O device, and when a data input device is specified, it is input from the specified I/O device. The data processing system is configured to temporarily store the data in the external storage device and then send it to the computer via the LAN.