JPS58101335A - Data transfer device - Google Patents

Abstract

PURPOSE:To speed up the data transfer at a long-distance communication line by monitoring and interpreting the command of data transfer provided by a central processing unit for an input and output device and transferring data in the block unit consisting of data of a plural bytes. CONSTITUTION:A pair of data transfer devices 14 are connected to both ends of a long-distance communication line 4, and they are connected with a central processing unit 1 or an input and output device 13. A data buffer circuit 10 of one-several blocks' share is provided in the device 14, and a command given from the central processing unit 1 to the input and output device 13 is monitored and interpreted with a command monitoring circuit 15. After the interpretation of the command, signal transmission/reception to and from the central processing unit 1 or the device 13 is done by an interface controlling circuit 16 through a transmission/reception circuit 9 and a control circuit 8 according to the content of the command. The data transfer to the center processing device 1 and the device 13 is done by providing the command to the device 13 directly.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention provides a data processing system in which a central processing unit and an input/output device are installed separated by a long distance using a high-bandwidth, low-loss signal path such as an optical 7-iper. This relates to a device that distributes power to an input/output device to control high-speed data transfer.

Figure 1 shows a conventional method for transferring data through a long-distance communication path, and is an example of the case where a communication control device is used. In Figure 1, a pair of modem devices 8 are connected to both ends of a long-distance communication path number, and a communication control device B or a terminal device 6 is connected to each.
11 are connected. In this system, the modem device 8 converts the signal into a signal suitable for the long-distance communication path 4, and data can be transferred between the central processing unit 1 and the terminal device 5 over a long distance. c requires control of data transfer by the communication control device 2, and therefore the central processing unit 1 must give a control command to the communication control device 8 before starting data transfer. In this rounding, communication control device 2
In addition to the transmitting/receiving circuit 9 and the data buffer circuit 1O, there are a machine number decoding circuit 6 for decoding the machine number of the communication control device given from the central processing unit 1, and a command decoding circuit 7 for decoding control commands. and a control circuit 8, which control data transfer in response to control commands given to the communication control device 2 from the central processing unit 1.

FIG. 2 shows another conventional method for transmitting data through a long-distance communication path, using an inter-channel coupling device. In FIG. 2, a pair of inter-channel coupling devices 11 are connected to both ends of a long-distance high-signal channel, and a central processing unit 1 is connected to each of them. In this method, since the signal is converted into a good signal suitable for the long-distance communication path 4 in the inter-channel coupling device 11,
Mutual data transfer is possible, but for this purpose it is necessary to control the data transfer by the inter-channel coupling device 111. Therefore, before starting data transfer between central processing units, each central processing unit l must A control command must be given to the inter-channel coupling device 11 to perform the operation. For this purpose, the channel connection device 2 includes a transmitting/receiving circuit 9,
In addition to the data buffer circuit 10 and the signal conversion circuit 1a, a device number decoding circuit 6 for decoding the device number of the inter-channel coupling device 11
And a command decoding circuit that decodes control commands? and control circuit 8
These K control the data transfer by receiving control commands given from the central processing unit 1 to the inter-channel coupling device 11, respectively.

As described above, when using one communication control device or inter-channel coupling device, the central processing unit controls the communication control device or inter-channel coupling device in advance to prepare for data transfer before starting data transfer. It is necessary to give commands. For this reason, even in systems where the central processing unit and input/output devices are directly connected via a short-distance communication path, and the central processing unit only needs to directly give data transfer rounding control commands to the input/output devices, the central When using a communication control device or inter-channel coupling device that connects a processing device and an input/output device via a long-distance communication path, the program or control function in the central processing unit or input/output device must be modified. Long distance data transfer was not possible.

FIG. 8 shows yet another conventional method for transferring data over a long distance communication path. In FIG. 8, a pair of data transfer devices 1c14 are connected to both ends of the long distance communication path 4, and each has a central processing unit 1 or an input/output device 18.
is connected. When the signal from the central processing unit 1 is received by the transmitting/receiving circuit 9 in the data transfer device 14 on the central processing unit 1 side, the signal conversion circuit 1z converts it into a signal suitable for the long distance communication path 4, and converts it into a signal suitable for the long distance communication path 4. Send to the road number. This converted signal is sent to the input/output device 1811 through the long distance signal path 4.
The signal conversion circuit 1s in the data transfer device 14 of g receives the signal, returns it to the original signal through the transmission/reception circuit 9, and transmits it to the input/output device 18. On the other hand, signals from the input/output device 18 are also sent to the central processing unit 1 through the same procedure.

This method has the advantage that the central processing unit or the input/output device does not need to be modified, but the signal output from the central processing unit 1 (or the input/output device 18) is sent to the data transfer device 14, The input/output device 1 passes through the data transfer device 14.
If the time required to reach 8 (or central processing unit 1) is T, then generally four signal exchanges are required to transfer one byte of data (i.e. 8 Raise the RV I N signal.

■The channel raises the 8RVOUT signal in response to a service request. ■I10 is 8 when a service request is received.
Lower the BY I N signal. ■Channel is 8 RV
IN#! Bottom>! 8RVOUT (llt lower.

), it takes 4T. As the length of the long-distance communication path 4 increases, the value of T increases accordingly, so the time 4T required to transfer 1 byte of data increases, and therefore the data transfer rate (1/4T) increases.
) has the disadvantage that it becomes small.

SUMMARY OF THE INVENTION An object of the present invention is to improve the drawbacks of the conventional data transfer apparatus described above and to realize a high-speed data transfer apparatus for long-distance communication paths.

Therefore, in the present invention, the data transfer is controlled by monitoring and decoding the data transfer command given by the central processing unit to the input/output device. Then, instead of exchanging signals with the communication channel one byte at a time, a block consisting of multiple bytes of data is created and data is transferred in units of this block. If you do this, 4
Since one block of data can be transferred by exchanging signals once, the time required for data transfer is reduced, and the data transfer speed is correspondingly increased. If the data amount of one block is D bytes, the data transfer rate is D/4T.

An embodiment of the present invention is shown in FIG. In FIG. 4, a pair of data transfer devices 14 are connected to both ends of the long-distance communication path 4, and the central processing unit 1 or input/output device 18 is connected to each, as in FIG. 8. Tasoshi, #I4
In the case of the figure, in addition to the control circuit 8, the transmission/reception circuit 0, and the signal conversion circuit 12, the data transfer device 14 includes a data buffer circuit IO1 for one to several blocks, and a human output device #1 from the central processing unit #1.
A command monitor circuit 15 monitors and decodes the command given to L18, and after decoding the command, a transmitting/receiving circuit 9 according to the command contents.
and the central processing unit l or the input/output device 1 through the control circuit 8
Interface control circuit 1 that exchanges signals with B
It is characterized by having 6.

Data transfer between the central processing unit 1 and the input/output device 18 is performed by the central processing unit 1 directly giving commands to the input/output device 18. Therefore, it is not necessary to provide a device number decoding circuit in the data transfer device 14 for decoding the device number of one data transfer device 14, unlike when a communication control device or an inter-channel coupling device is used. 1 and the input/output device 1B need not be modified for data transfer over a long-distance communication path.

A series of operations based on the above commands generally consists of eight sequences: a startup sequence, a data transfer sequence, and a termination sequence. Of these, the present invention relates to speeding up the data transfer sequence part.

First, according to the startup sequence, the central processing unit 1 issues a command to the input/output device 111B. The operation of the data transfer device 14 in this startup sequence is the same as the conventional system shown in FIG. , the signal conversion circuit 18 converts the signal into a signal suitable for the long-distance communication path 4, and sends it to the communication path 4. Signals from the input/output device 18 are also sent to the central processing unit 1 through the same procedure.
send to At this time, the command monitor circuit 15 monitors the signal exchange between the central processing unit 1 and the input/output device 18, and after confirming that the input/output device 1B correctly receives the command, 1! Decipher the contents of the WI Order. If the command is a read command or a write command, the contents of the command are transmitted to the interface control circuit 16 at the end of the startup sequence.

11L command, that is, from the input/output device 18 to the central processing unit 1
In the case of data transfer to the input/output device 18, first, the interface control circuit 16 in the data transfer device l needle of the input/output device 18 exchanges signals with the input/output device 18 through the transmitting/receiving circuit 9. Data is taken into the data buffer circuit IO.

When the data buffer circuit IO becomes full, the data is transferred in blocks through the long distance communication path 4 to the data buffer circuit 10 in the data transfer device 14 on the central processing unit l side. When this data buffer circuit IO becomes full, the interface control circuit 16 of the data transfer device 14 on the central processing unit side exchanges signals with the central processing unit 1 through the transmission/reception circuit 9, and transfers the data buffer 7 to the central processing unit 1. Sends data from circuit IO one byte at a time.

In the case of a write command, that is, data transfer from the central processing unit 1 to the input/output device 18, first the interface control circuit 16 in the data transfer device 14 of the central processing unit III
exchanges signals with the central processing unit l, and takes in one to several blocks of data into the data buffer circuit lO. When the data buffer circuit IO becomes full, the data is transferred in blocks to the data buffer circuit IO in the data transfer device 14 on the input/output device 1B side through the long distance communication path number. When this data buffer circuit 10 becomes full, the interface control circuit 16 of the data transfer device 14 on the input/output device side exchanges signals with the input/output device 18, and sends data one byte at a time to the input/output value fillB.

When the central processing unit 1 or the input/output device 1B instructs the end of the data transfer sequence, the operation returns to the conventional system again, and each data transfer device 14 bypasses the corresponding data buffer circuit 10 and transfers the data to the central processing unit 1B. 1 or the input/output device 18 for exchanging termination sequence signals.

However, if the command is a command other than a read command or a write command, that is, a command without data transfer, or if the command is not correctly received by the input/output device 18, there is no data transfer sequence, so even after the start-up sequence ends. Similarly to the conventional system, the data buffer circuit 10 is bypassed to exchange signals.

As explained above, according to the data transfer device of the present invention,
The central processing unit and input/output device can exchange signals without being aware of the data transfer device, and there is no need to modify the programs or control functions in the central processing unit or input/output device, and the current It can also be easily introduced into the system. Furthermore, since data transfer to and from the communication path is block transfer, the number of times signals are exchanged through the communication path is reduced, and high-speed data transfer is possible.

[Brief explanation of the drawing]

1 to 8 are diagrams showing examples of conventional methods for transferring data through long-distance communication channels, and FIG. 4 is a diagram showing an embodiment of the present invention. l...Central processing unit, 4...Long distance communication path, 8...
- Control circuit, 9... Transmission/reception circuit, 10... Data buffer circuit, 12... Signal conversion circuit, 1B... Input/output device, 14... Data transfer device, 15... Command monitor circuit , 16...interface control circuit. Figure 1 Figure 2 Figure 3 Figure 4

Claims (1)

[Claims] L A data transfer device used by connecting to the central processing unit or input/output device of a data processing system in which the central processing unit and the input/output device are connected through a communication path,
Alternatively, a data buffer means for storing several blocks of data, a monitor means for monitoring data transfer commands and their responses exchanged between the central processing unit and the input/output device, and when the data transfer is decoded by the monitor means,
Data is exchanged between the central processing unit or the input/output device in predetermined byte units and stored in the data buffer means, and when the data buffer means is full, the l
Alternatively, a data transfer device comprising: control means for successively sending several blocks of data to the communication channel.