JPH0243654A - Data quantity controller - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed Description of the Invention] [Summary] This invention relates to a data amount control device that can store data exceeding the buffer capacity of a control device in a previous stage buffer, and can efficiently transmit data by multiplexing. The purpose of the present invention is to provide a data amount control device, which transfers data from a plurality of terminal devices between a plurality of systems in which a plurality of terminal devices are controlled by a control device to a first storage device with a predetermined capacity provided in the control device. In a communication system that performs multiplex transmission and reception via a storage means, it is provided between a plurality of terminal devices and a control device, and is common to the plurality of terminal devices. 1
A second storage means having a capacity equal to or greater than the amount of data obtained by subtracting a predetermined capacity of the storage means of data amount control means for storing data in an amount exceeding the capacity in the second storage means; The configuration is such that the data is transferred to the first storage means.

[Industrial Application Field] The present invention relates to a communication system that multiplexes transmission and reception from a plurality of terminal devices via a control device, and in particular, a communication system in which data exceeding the buffer capacity of the control device is stored in a previous stage buffer. The present invention relates to a datascape control device that can be used as a storage device.

In a facsimile machine or a system that sends and receives screen data to and from each other, when data is sent from multiple terminal devices via a control device, if the amount of data sent from each terminal device exceeds the data buffer capacity of the control device, Since data is held in the data memory of each terminal device and no further data can be input, usage efficiency decreases, and a method that can deal with this is desired.

[Conventional technology]

Figure 4 shows a block diagram of the multiplex communication system.
A plurality of terminal devices 1a+1b,'- and IA, IB,-.
・Data is transferred between control devices (Terminal Control)
In a system that transmits and receives via 2a and 2A (hereinafter referred to as T/C), there is 1 between T/C 2a and 2A.
It is connected by a main line, and data is transmitted by multiplexing.

In FIG. 5, terminal devices 1a (Ib, . . . , IA
, IB, -...) is the program section 11. in which the CPUIO and control programs are stored. data input button,
A keyboard 12 equipped with a destination selection button (or destination code input button), a transmission command button, etc. A display (hereinafter referred to as CRT) 13 on which input data, received data, etc. are displayed, and a printer section 14 that prints out the received data, etc.
Keyboard 12. Alternatively, a data memory 15 that stores input data from an external device (not shown). Data transmission processing unit 16 that edits the message of transmission data. and transmitting/receiving section 17
It is made up of.

The T/C 2a (same as 2A) includes a CPU 3O and a program section 21. which has a data transfer program. and a data buffer 22a.

With such a configuration and function, the data input to the terminal device 1a is stored in the data memo, and when the destination is selected and the transmission command button is pressed, the stored data is output and data transmission processing begins. The message is edited into a transmission message by the section 16 and sent from the transmitting/receiving section 17 to the T/C 2a. T/C2a
After being stored in the data buffer 22a, it is sent to the line and sent to the destination terminal devices IA and I via the T/C 2A
It is sent to either B or -.

Between terminal devices where data is sent and received in this way, T/
In order to reduce the load due to the amount of data on C2a, the amount of data that can be sent is determined in advance, or the amount of data is determined by pre-procedure processing at the time of connection using a protocol.

However, due to multiplexing, transmission data is also sent to the T/C 2a from terminal devices 1b and - other than the terminal device 1a,
Data that exceeds the transmission processing capacity of the T/C 2a may be accumulated in the data buffer 22a, reaching its storage capacity, and no more transmission data can be accepted.
2a, the order of transmission requests is memorized, and when the transfer from the data buffer 22a progresses and there is storage capacity, the transmission data is accepted in the order of the transmission request and transferred to the data buffer 22a.
Store in.

[Problem to be solved by the invention]

According to the above conventional method, even if the amount of data between individual terminal devices is controlled, if data is sent in excess of the processing capacity of the T/C due to multiplexing, it will be held in the data buffer within the T/C. Data transmission cannot always be performed smoothly because the data exceeds the capacity. In other words, when a peak occurs in the data transmitted from multiple terminal devices and exceeds the storage capacity of the data buffer of the T/C, the data transmission from the terminal devices is put into a busy state and is temporarily put on standby, and then retransmitted after a certain period of time. , reset, and other operations are required, and during this time the data is stored in the data memory of the terminal device. Furthermore, when data is input to the terminal device and the storage capacity of the data memory is reached, no more input can be made, resulting in a reduction in the usage efficiency of the terminal device.

An object of the present invention is to provide a data amount control device that can efficiently transmit data by multiplexing.

[Means to solve the problem]

FIG. 1 is a block diagram of the principle of the present invention.

In the figure, 1 is a plurality of terminal devices, 2 is a control device, 22
is a first storage means, 30 is provided between the plurality of terminal devices 1 and the control device 2, is common to the plurality of terminal devices 1, and is a first storage means from the maximum data amount transmitted from the plurality of terminal devices 1. A second storage means 31 having a capacity equal to or greater than the amount of data obtained by subtracting the predetermined capacity of the means 22 is provided between the plurality of terminal devices 1 and the control device 2, and the second storage means 31 is provided between the plurality of terminal devices 1 and the control device 2, Storage means 22
This data amount control means causes the second storage means 30 to store the amount of data exceeding the predetermined capacity when the data stored therein reaches a predetermined capacity.

Therefore, the configuration is such that the data stored in the second storage means 30 is transferred to the first storage means 22 when the first storage means 22 has data storage capacity.

[Effect]

The transmission data from the plurality of terminal devices 1 is sent to the first terminal of the control device 2.
When the amount of data stored in the first storage means 22 due to multiplexing reaches a predetermined capacity, the data amount control means 31 controls the amount of data that exceeds the predetermined capacity. The data is stored in the second storage means 30. Therefore, data transmitted from the terminal device 1 is sequentially stored in the second storage means 30. When the data stored in the first storage means 22 is sequentially sent out to the next line and there is storage capacity in the storage capacity of the first storage means 22, the data stored in the second storage means 30 is sent out to the next line. 1 storage means 22
will be forwarded to. That is, ■The amount of data that multiple terminal devices 1 send to T/C2 within time T is M.■The amount of data that T/C2 can process within time T is N.■■Multiple terminal devices 1 transmit at the protocol level. The time for monitoring is t.

Then, the amount of data held unprocessed by the T/C2 within a unit time is expressed as (M-N)/T.

At this time, if the time that triggers retransmission, reset, etc. in the terminal device 1 is t, the following formula holds true, ((M-N
)/T) t > (M/T) tl, °, t > (M
/M −N) tl −・−・−−−−−−Il) Therefore, by increasing the right side of equation (1), the probability of occurrence of retransmission, reset, etc. can be reduced. Here, ■ the amount of transmission data generated by the plurality of terminal devices 1 within time T is U; ■ the storage capacity of the second storage means 30 and the first storage means 22;
If the sum of the storage capacities of is S, then in general, N≦SOU -·······−(2). In the case of the conventional example, M=U in Equation 11, but if M=S, the right side of Equation 11 becomes a larger value than when M=U.

Therefore, the plurality of terminal devices 1 can smoothly transmit data to the T/C 2 with less load.

〔Example〕

An embodiment of the present invention will be described below with reference to FIGS. 2 and 3. The same reference numerals indicate the same objects throughout the figures. In FIG. 2, parts corresponding to those in FIG. 1 are shown surrounded by a dashed line.

In FIG. 2, the data amount control device 3 is provided in common to the plurality of terminal devices 1allb+-, -, at the front stage of the T/C 2b, and includes a data memory 30a and a data amount control section 31a.

The data memory 30a includes terminal devices 1a, 1b+...-
・Has a capacity greater than or equal to the maximum amount of data to be transmitted minus the capacity of the data buffer 22a of the T/C 2b, and when the data buffer 22a reaches a predetermined capacity, the amount of data described below Under the control of the control unit 31a, transmission data sent from the terminal devices 1a+1b, - is sequentially stored.

The data amount control unit 31a controls the terminal devices 1a, lb, .
is transmitted from T/ and stored in the data buffer 22a.
When the amount of data exceeding the transmission processing capacity of C2b is accumulated and reaches a predetermined capacity, a notification is received and the amount of data exceeding the predetermined capacity is stored in the data memory 30a, and the data stored in the data buffer 22a is stored. is transmitted and a certain amount of storage capacity is available in the data buffer 22a, T/
Upon receiving the notification from the C2b, the data stored in the data memory 30a is transferred to the data buffer 22a.

In addition, the T/C 2b includes a CPU 20a, a program section 21
a.

and a data buffer 22a, which transfers transmitted and received data, and when the amount of data exceeding the transmission processing capacity reaches a predetermined capacity of the data buffer 22a, it notifies the data amount control section 31a to that effect, and also controls the data buffer 22a. 22a
When a certain amount of storage capacity is available, the data amount control unit 31a is notified of this fact.

Since it has such a configuration and function, the operation will be explained with reference to the flowchart in FIG. 3.

(2) First, transmission data from the terminal devices 1a, lb, - is sent to the T/C 2b via the data amount control device 3, stored in the data buffer 22a, and immediately sent out to the line.

(2) Data exceeding the transmission processing capacity of the T/C 2b is accumulated in the data buffer 22a, and when the data amount reaches a predetermined capacity, the data amount control device 3 is notified.

■Then, the data amount control unit 31a selects the terminal device 1a+lb
Subsequent data from t are sequentially stored in the data memory 30a.

■When the data stored in the data buffer 22a of the T/C 2b is transmitted and a certain amount of storage capacity is available, the data in the data memory 30a is transferred to the T/C 2b by a corresponding amount in the order in which it was stored.
The data is sent to C2b and stored in data buffer 22a.

In this way, since the sum of the storage capacities of the data memory 30a and the data buffer 22a corresponds to the maximum amount of data to be sent from the terminal devices 1a, lb, -, the terminal devices 1a+lb,
- Transmission data is sent out smoothly, the load on the T/C 2b is reduced, the probability of occurrence of retransmission, reset, etc. is reduced, and transmission efficiency can be increased.

〔Effect of the invention〕

As explained above, according to the present invention, by providing a second storage means common to a plurality of terminal devices and a data amount control means for controlling storage and transmission of data to the second storage means, Since the load on the control device can be reduced, the transmission of data from the terminal device is facilitated, the probability of occurrence of retransmission, reset, etc. is reduced, and transmission efficiency can be improved.

FIG. 5 is a block diagram showing a conventional example.

In the figure, 1. la and lb are terminal devices, 2a, 2b, 2A are T/C.

22 is a first storage means; 30 is a second storage means; 31 is a data amount control means; 31a indicates a data amount control section.

2 is a control device; 3 is a data amount control device; 22a is a data buffer; 30a is data memory;

[Brief explanation of the drawing]

Fig. 1 is a block diagram of the principle of the present invention, Fig. 2 is a block diagram showing an embodiment of the invention, Fig. 3 is a flowchart of the embodiment, and Fig. 4 is a block diagram showing the communication system. Kuri F'rosov [child 1 drawing hand? Genji O and 1 Dari's 20-Tema-F 1,000 3 ■

Claims (1)

[Claims] Data from a plurality of terminal devices (1) is provided to the control device (2) between a plurality of systems in which a plurality of terminal devices (1) are controlled by a control device (2). of the predetermined capacity
In a communication system that performs multiplex transmission and reception via a storage means (22), provided between the plurality of terminal devices (1) and the control device (2), the plurality of terminal devices (1) In common, the plurality of terminal devices (
a second storage means (30) having a capacity equal to or greater than the amount of data obtained by subtracting a predetermined capacity of the first storage means (22) from the maximum amount of data transmitted from 1); and the plurality of terminal devices (1). When the data transmitted from and stored in the first storage means (22) reaches a predetermined capacity, the amount of data exceeding the predetermined capacity is stored in the second storage means (30). and a control means (31), when the first storage means (22) has a data storage capacity, the data stored in the second storage means (30) is transferred to the first storage means (22). ).