JPS58151149A - Transmission and reception system of communicating device signal - Google Patents

Abstract

PURPOSE:To decrease the burden on a central processing device and to confirm the normality of other stations including the central processing device, by transmitting and receiving a fill-in signal comprising a specific pattern at prescribed intervals, in a communicating device. CONSTITUTION:In transmitting the fill-in signal, an instruction is fed from the central processing device CP1 to a communicating device 2 via an information transmission line 3 and a 1F4 at each T1sec. In the device 2, a fill-in signal comprising the specific pattern is formed in a buffer memory and the fill-in signal 8 is transmitted to a line 6 for T2sec (T2<=T1) automatically from a 1F7 at intervals (t)(t<T1). When a signal 9 to be transmitted exists in this timing additionally, the signal is transmitted with priority. When the fill-in signal thus transmitted arrives, it is formed and transmitted at the device 2 and since the forming is based on the instruction of the CP1, the normality of the communication system including the CP1 is confirmed. Further, when the fill-in signal being n-set (n>=1) or over and signals other than the fill-in signal are received for a prescribed period T3sec, it is reported to the CP1 at each T3sec. It is not reported for the signals being <n.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention notifies other stations of the normality of its own station, including a central processing unit, by transmitting a fill-in signal consisting of a specific number or turn at regular intervals in a communication device. Alternatively, the present invention relates to a communication device signal transmission/reception method for confirming the normality of other stations including a central processing unit by receiving a signal other than a fill-in signal.

This type of communication system is configured as shown in FIG. In FIG. 1, 1 is a central processing unit, 2 is a communication device, 3 is an information transmission path connecting the central processing unit 1 and the communication device 2,
4 is an information transmission path interface section in the communication device 2;
5 is a buffer memory, 6 is a line, and 7 is a line interface section in the communication device 2. FIG. 2 shows an example of signals transmitted and received in such a communication system. In FIG. 2, a format is described based on the HDLC method as a transmission control procedure. F is a synchronization flag, A is an address note assigned to a communication device, C is a control foot used for controlling the order of signals, etc., ■ is a user data section,
Fe2 is a check motherboard that checks the normality of the signal.

Now, when transmitting certain information to another station, the central processing unit 1 assembles the user data section (2) and temporarily stores it in the buffer memory 5 via the information transmission path 3 and the information transmission path interface 4. The communication device 2 performs address, route A1 control, gate C1 check, and other functions necessary for transmission control procedures.
A tag FC8 is added thereto, and the signal is sent to the line 6 from the line interface section 7 together with the synchronization flag F. Conversely, when information is obtained from another station, the signal is taken in via the line 6 and line interface section and temporarily stored in the buffer memory 5. Thereafter, only the user data section (2) is transmitted to the central processing unit 1 via the information transmission path interface section 4 and the information transmission path 3.

In such communication systems, a method is increasingly adopted in which the normality of a station including the central processing unit 1 is communicated from one station to another station, and from another station to the own station at regular intervals.

Conventionally, when a station no longer receives a signal, it is necessary to distinguish whether there is no signal to be sent from another station or a failure has occurred. In order to notify the other station (or the own station) of the normality of the other station, the central processing unit 1 transmits a specific A' turn signal, which has the same format as the user signal, through the same route as the user signal. It notifies other stations of the normality of its own station, and also receives signals through the same route as normal signals, and if the central processing unit 1 determines that the signal has a specific pattern, the central processing unit 1 of the other station receives the signal. The method used was to check the normality of other stations.

For this reason, when the interval between sending and receiving specific signals is shortened, the load on the central processing unit 1 becomes large, and the effect of distributing transmission control functions to the communication device 2 is not fully realized. was.

Recently, in addition to the HDLC method, CC has also been introduced as a transmission control procedure.
The ITT and A7 signaling systems are used, which adopt the concept of positioning fill-in signals, which are transmitted and received at regular intervals, as signals for transmission control procedures. From this point of view, the conventional method of forming a signal to notify the normality of a communication system in a central processing unit and sending it as it is via a communication device is unnatural due to the division of functions; 2 should be responsible for transmitting and receiving fill-in signals or signals equivalent thereto, but this is not the case, which is a problem from a functional and design perspective.

In order to solve these problems, the present invention allows the communication device 2 to transmit and receive fill-in signals consisting of specific signals, and notifies the normality of the link including the central processing unit 1 between the communication systems. The drawings will be described in detail below.

In the present invention, a signal consisting of a specific turn is transmitted and received in the following manner. That is, when transmitting and receiving data, the central processing unit 1 periodically issues an instruction to the communication device 2 via the information transmission path 3 and the information transmission path interface section 4 every T1 seconds. In the communication device 2, a fill-in signal consisting of a specific pattern is formed on the buffer and memory based on the instruction, and the fill-in signal is automatically transmitted from the line interface section 7 every second at intervals shorter than the period of 71 seconds of the instruction from the central heating device 1. A fill-in signal is sent to line 6 for 12 seconds (T2≦T1).

If there is another signal to be sent at the timing when the fill-in signal is sent, the sending of the fill-in signal is stopped while that signal is being sent. The transmission of the fill-in signal during this transmission is shown in FIG. After receiving instructions from the central processing unit every T1 seconds, the fill-in signal 8 is repeatedly sent out at intervals of t seconds during 12 seconds, but when there is a signal 9 to be sent to another station at the timing of sending out the fill-in signal 8. is that signal 9
Priority is given to sending out the fill-in signal 8, and the fill-in signal 8 is not sent out.

When the fill-in signal sent out in this way arrives, it is formed and sent out by the communication device 2, but since it is based on the instructions from the central processing unit 1, the normality of the communication system including the central processing unit 1 is affected. This can be confirmed. Note that the normal command method for issuing instructions from the central processing unit 1 to the communication device 2 does not mean that the normality of the user data transmission route between the central processing unit 1 and the buffer memory 5 has been checked. In a system where it is necessary to ensure the specified A? It is necessary to use a method in which a signal consisting of a turn (not necessarily the same as a fill-in signal or a turn) is transmitted via a normal transmission route, and the communication device 2 determines that the signal is an instruction from the central processing unit 1. be.

On the other hand, as shown in Figure 4, n pieces (
n>1) When a fill-in signal or a signal other than a fill-in signal is received, the reception of the signal is reported to the central processing unit 1 every 73 seconds. If the number is less than n, it is not reported to the central processing unit. As with sending,
In a system that requires absolute security, one way to report this is to send a signal consisting of a certain number of turns (not necessarily the same number of turns as the fill-in signal) to the central processing unit 1 on the buffer memory 5. It is necessary to form a signal, transmit it to the central processing unit 1 via a normal signal reception route, and then confirm that there is a received signal in the central processing unit 1.

Since fill-in signals are transmitted and received at regular intervals in step 2, the burden on the central processing unit 1 is reduced, and the normality of other stations including the central processing unit 1 can be confirmed. In addition, the present invention
In transmission control systems such as CITT and A7 signaling systems, a fill-in signal consisting of a specific turn is positioned as a signal in the transmission control procedure, so it is a natural method in terms of functional division when all the transmission control procedures are assigned to communication equipment. This has the advantage of being easier to understand from a design standpoint.

[Brief explanation of the drawing]

FIG. 1 is a schematic diagram of a communication system, and FIG. 2 is an example of the format of signals transmitted and received in the communication system of FIG. FIG. 3 is a diagram showing the relationship between the fill-in signal and the signal to be sent to another station in the case of transmission according to the present invention, and FIG. 4 is a diagram showing the report of signal reception to the central processing unit in the case of reception according to the present invention. FIG. DESCRIPTION OF SYMBOLS 1... Central processing unit, 2... Communication device, 3... Information transmission path connecting central processing unit 1 and communication device 2, 4...
Information transmission path interface unit in the communication device 2, 5.
... Buffer memory, 6... Line, 7... Line interface section in communication device 2, 8... Fill-in signal, 9... Signal to be sent to another station, F... Synchronization flag, A... ...Address/Guito, C...Control No.e
), Fe2...check part. Figure 1 Continued from page 1 0 Inventor Masaaki Nagai Inside NEC Corporation, 5-33-1 Shiba, Minato-ku, Tokyo

Claims (1)

[Claims] In a communication device connected to a central processing unit, accommodating a communication line, and transmitting and receiving signals, the communication device receives an instruction from the central processing unit to transmit a fill-in signal every T1 seconds, and receives an instruction from the central processing unit. , If there is another signal to be sent at the timing of transmitting the fill-in signal, the transmission of the fill-in signal is stopped during the transmission of that signal, and when n (n≧1) or more fill-in signals or fill-in A communication device signal transmission and reception method characterized in that when a signal other than a signal is received, the reception of the signal is reported to a central processing unit every 13 seconds.