JPS62216440A - Communication control method - Google Patents

Abstract

PURPOSE:To eliminate the need for complicated procedures such as error resending control etc., by making a transmission line having parity check function duplex and adopting data of a transmission line in which data transfer error is not found. CONSTITUTION:Another set of transmission line system consisting of a transmission line 15 and accompanying PG14, PC16 is added in parallel to make the system duplex and signal data are transferred in parallel. A processor 9 is made to adopt data of a transmission line in which data transfer error is not found. Accordingly, a control line that returns from a receiving side to a transmitting side is not used. Thereby, it is not necessary to prepare a software program that interprets a error forming signal in a processor 1 of the transmitting side and resends transfer data from a buffer memory 2, and the transfer of correct signal data can be made by inexpensive and relatively simple hardware.

Description

[Detailed Description of the Invention] [Summary] Complicated procedures such as error retransmission control can be eliminated by duplicating transmission paths with a parity check function and using data from transmission paths in which no data transfer errors have been detected. Made unnecessary.

[Industrial application field]

The present invention utilizes a digital data communication system to
For example, related to improvements in communication control methods for devices that convert input signals from subscribers into digital and encoded data into computer-specific terminology when searching for information such as train seat reservations or real estate information. It is.

At this time, if an error occurs in the transferred data for some reason, the error is detected in the receiving microcomputer in the above device, and an error notification signal is sent from the same microcomputer to the transmitting microcomputer, and the data is transmitted. Highly reliable data communication is achieved through a control mechanism in which the processor in the side microcomputer automatically retransmits data.In manufacturing the above control mechanism, we try to make it as inexpensive as possible. things are desirable.

[Conventional technology]

FIG. 2 is a block diagram for explaining a conventional communication control method.

The operation when transferring data using a conventional communication control method will be described below.

The data of the signal sent from the subscriber is stored in the memory (
(not shown) and the same microcomputer 12
After being decoded and processed by the processor 1 in the computer according to instructions from a pre-made software program,
The above data is written to buffer memory 2 on the sending side,
After a parity focus is added by a parity generator (hereinafter referred to as PG) 3, the signal is sent via a transmission line 4 to a parity checker (hereinafter referred to as PC) 5 in a microcomputer 13 on the receiving side, which is shown surrounded by a dotted line. Errors in the signal data are detected.

In the PC 5, when an error in signal data caused by external noise such as signal leakage from an adjacent printed board or wiring is detected, a signal notifying the error is sent to the control line 10 and the transmitting side. The data is sent to the transmitting processor 1 via the buffer memory 2 and the control line 11.

The transmitting side processor 1 issues a command to send the transfer data again from the transmitting side buffer memory 2 using a pre-written software program, and sends the data to the receiving side.

In this way, the above process is repeated several times until the correct data is sent to the receiver.

If an error is detected in PO2 on the receiving side even after repeating the above process several times, a separately provided alarm circuit (not shown) generates an alarm, and the transmission line, buffer memory, etc. are inspected. .

On the other hand, if it is found that the data is normal as a result of the check by PO2 on the receiving side, a normal notification signal is sent to the receiving side processor 9 via the control line 6, buffer memory 7, and control line 8. Line 10, buffer memory 2 on the sending side
, a normal notification signal is also sent to the transmitting side processor 1 via the control line 11 to notify that the next signal data can be transferred.

[Problem that the invention seeks to solve]

However, according to the above-mentioned communication control method, the labor cost for creating a software program that causes the transmitting processor to decode the error notification signal and retransmit the signal data increases significantly, making the production cost too high. There was a problem.

[Means for solving problems]

In the present invention, as shown in FIG. 1, another transmission line system consisting of the transmission line 15 and accompanying PCl3 and PCl3 is added in parallel to make it redundant, and signal data is transferred in parallel, and The processor 9 on the receiving side uses data from a transmission line in which no data transfer error has been detected.

[Effect]

Therefore, in the present invention, unlike the conventional example, the control line 4H that returns from the receiving side to the transmitting side is not used, and therefore the error notification signal is decoded in the processor 1 on the transmitting side and the transfer data is transferred from the buffer memory 2. There is no need to create a software program to retransmit data in advance.

Therefore, correct signal data transfer can be achieved with inexpensive and relatively simple hardware.

〔Example〕

FIG. 1 is a block diagram for explaining a communication control method according to the present invention.

The same reference numerals refer to the same objects throughout the design.

For example, signal data sent from a subscriber is stored in a memory (not shown) in the microcomputer 12 on the sending side.
and is written into the buffer memory 2 by the processor 1.

The above data is stored from buffer memory 2 to PO2 and 14.
After a parity bit is added to each data having the same content, it is sent to PO2 and PO16 on the receiving side via transmission line 4.15, and error detection in the signal data is performed.

When an error is detected in PO2 or 16, an error notification signal is inputted via control line 6.17 to an area (not shown) for storing status information in bathophore memory 7, and further via control line 8.18. The signal data is sent to the processor 9 via the rough 1-ware program to decode errors in the signal data.

At this time, if no error is detected in the signal data sent from either transmission line 4 or 15, the signal data sent via transmission line 4, for example, is adopted as normal data. , it is predetermined in advance that the data will be processed by the processor 9 and then sent to the next device (not shown).

Further, when an error is detected in the data received from the transmission line 4, it is confirmed that there is no error in the data from the other transmission line L5, and then the data is adopted and processed by the processor 9.

When an error is detected in the received data on both of the above two transmission lines 4.15, a separate alarm circuit (not shown) is installed.
An alarm is issued and the transmission line, buffer memory, etc. are inspected.

〔Effect of the invention〕

As explained above, in the communication control method according to the present invention, the transmission line system is duplicated and signal data is transferred in parallel, and the transmission line system in which no data transfer error is detected in the receiving processor By adopting this data, highly reliable signal data transfer can be realized with an inexpensive and relatively simple hardware circuit.

[Brief explanation of drawings]

FIG. 1 is a block diagram for explaining a communication control method according to the present invention, and FIG. 2 is a block diagram for explaining a conventional communication control method. In the figure, 1 is the processor on the sending side, 2 is the buffer memory on the sending side, 3.14 is the parity generator (PG), and 4.15
is the transmission line, 5.16 is the parity checker (PC), 6.8.17
．． 18 is a control line, 7 is a buffer memory on the receiving side, 9 is a processor on the receiving side, 12 is a microcomputer on the transmitting side, and 13 is a microcomputer on the receiving side.

Claims (1)

[Claims] A parity bit is attached to the transmitted data, and the receiving side uses a parity check to detect data transfer errors.The transmission line is duplicated, and the data from the transmission line where no data transfer error is detected is adopted. A communication control method characterized by: