JPS62249543A - Data broadcasting method - Google Patents

Abstract

PURPOSE:To reduce the influence to be exerted upon a receiving station with fast completion of recording preparation by storing broadcasting data in the buffer memories of all receiving stations by a transmitting station and monitoring the near overflow of a buffer memory in a receiving station with the latest completion of recording preparation. CONSTITUTION:After storing broadcasting data in a buffer memory 18, the transmitting station requests the start of respective receiving stations to broadcast the data. Respective receiving stations store the sent data in respective buffer memories 28. The broadcasting is executed independently of the completion of the recording preparation of all the receiving stations. The transmitting station discriminates whether the memory 28 in the receiving station with the latest completion of the recording preparation is near overflow or not, and at no detection of the near overflow, continues the broadcasting, and at the detection, stops the broadcasting to all the receiving stations. When detecting nonoverflow of respective receiving stations, the transmitting station restarts the broadcasting. Thereby, the receiving station with fast completion of recording preparation can record the broadcasting data faster than the slow receiving station. Consequently, the influence of the receiving station with slow completion of recording preparation to the fast receiving station can be reduced.

Description

[Detailed description of the invention] Industrial applications The present invention relates to a data broadcasting method.

2. Description of the Related Art Conventionally, when transmitting the same data to multiple destinations at the same time in a data transmission device such as a facsimile machine, a transmitting station waits for all receiving stations to complete recording preparations before transmitting the data simultaneously.

Problems to be Solved by the Invention However, in this data broadcasting method, since the transmitting station cannot start data transmission until all receiving stations are ready for recording, it is difficult to receive data as soon as recording is ready. There is a problem in that data reception is delayed due to the influence of slow receiving stations.

SUMMARY OF THE INVENTION In view of the above problems, it is an object of the present invention to provide a data broadcasting method that can reduce the influence of a receiving station that completes recording preparation late on a receiving station that completes recording preparation quickly.

Means for Solving the Problems In order to solve the above-mentioned problems, the present invention provides a backup memory for storing received data in the receiving station, and allows the transmitting station to transmit broadcast data regardless of whether all receiving stations are ready for recording. It is transmitted to all receiving stations and stored in their respective backup memories, and the transmitting station also stops broadcasting to all receiving stations when it detects a near overflow of the backup memory of the latest receiving station that is ready for recording. , a special feature characterized in that when the receiving station starts recording, broadcasting is restarted.The present invention is characterized in that, according to the above-mentioned method, the receiving station that is early in completing preparation for recording receives the broadcasting data stored in the buffer memory. It is possible to start recording earlier than a receiving station that is slow to complete recording preparation.

EXAMPLES Hereinafter, the present invention will be described in detail with reference to the drawings. FIG. 1 is a block diagram showing an embodiment of the data broadcasting system according to the present invention, in which a transmission control section 10 and each reception control section 20
A case is shown in which these are connected via line interfaces (I/F) 30a, 30b and a branch service 31.

The control unit 10 includes a central processing unit (CPU) 11.
21, a data input interface (I/F) 12,
A read-only memory (ROM) 13.23 that stores the execution programs of the CPU 11.21 and the CP
U 1.1.21 Random access memory (RAM) 14, including a working area, etc., and a display section 15.5
, a line interface 16.26, a transmission control unit 17,n for controlling transmitted and received data, a buffer memory 18.28 for temporarily storing data during broadcasting, and a data recording device (not shown) connected Data output interface 2
It has 9. The line 32 includes data from the transmission control unit 10 to the reception control unit, and data from the reception control unit to the transmission control unit 10.
A recording preparation completion notification (ANS, BACK) is transmitted to the

2 and 3 show the operation sequences of the transmission control section 10 and the reception control section of FIG. 1. FIG. 2 shows normal operation, and FIG. This shows the case where

In FIG. 2, after the transmitting station stores the data to be broadcast in the buffer memory 18, it requests each receiving station to start up and broadcasts the data. The receiving station stores the sent data in buffer memory 4. This broadcast is performed regardless of whether all receiving stations are ready for recording.

Here, the transmitting station answers whether the buffer memory 28 of the receiving station that is the latest to complete recording preparation is near overflow.
It is detected by the back logical sum, and if it is not detected, the broadcast continues. Each receiving station sequentially records data in the buffer memory path starting with the earliest receiving station that is ready for recording.

On the other hand, in FIG. 3, when the transmitting station detects a near overflow of the buffer memo IJ 28 of the receiving station that is the latest to complete recording preparation by using the logical sum of the answer and the bank, it stops broadcasting to all receiving stations. .

Next, when the transmitting station detects non-overflows from all receiving stations by ORing the non-overflows from each receiving station, it resumes broadcasting. The transmitting station always logically detects non-overflow of the receiving station, and continues broadcasting to all receiving stations as long as there is no near overflow of the receiving station that is the latest to complete recording preparation.

Therefore, a receiving station that completes recording preparation earlier can record broadcast data earlier than a receiving station that is slower.

DETAILED DESCRIPTION OF THE INVENTION As described above, the present invention allows a transmitting station to store broadcast data in the buffer memories of all receiving stations, and to monitor the near overflow of the buffer memory of the receiving station that is the latest to complete recording preparation. Since transmission of the information data is stopped or restarted, a receiving station that completes recording preparation earlier can complete recording earlier than a receiving station that completes recording preparation earlier by the amount of backup memory capacity of the receiving station.

[Brief explanation of drawings]

FIG. 1 is a block diagram showing an embodiment of a data broadcasting system according to the present invention, FIG. 2 is a diagram showing a normal operation sequence of the system of FIG. 1, and FIG. 3 is a buffer memory of a receiving station. FIG. 3 is a diagram illustrating an operation sequence at a time of near overflow. 10... transmitting station control section, addition... receiving station control section, 11
．． 21... Central processing unit (CPU), 12... Data input interface, 13, Z3... Read only memory (ROM), 14.24... Random access memory (RAM), 16.26...・Line control section, 17
, n...Transmission control unit, 18, A...Buffer memory, 4...Data output interface.

Claims (1)

[Claims] The transmitting station transmits the broadcast data to all receiving stations and stores it in their respective buffer memories regardless of whether all receiving stations are ready for recording, and detects an overflow in the buffer memory of the receiving station that is the latest to complete recording preparations. A data broadcasting method characterized in that data transmission to all receiving stations is stopped when this is detected, and data transmission to all receiving stations is resumed when the latest receiving station that has completed recording preparation starts recording. .