JPH06164585A - 1:n communication system - Google Patents

Abstract

PURPOSE:To obtain a 1:N communication system in which a slave machine can output a request to transmit arbitrarily to a master machine, and communication between the master machine and the arbitrary number of the slave machines can be executed. CONSTITUTION:Each slave machine C1, C2,... CN is provided with a computer 6 and two standard interface ports 2,3 controlled by the computer 6 respectively. Information attached with an ID code issued from the master machine P to the slave machines C1, C2,... CN is inputted from the interface port 2 of either of slave machines C1, C2,... Cn. When the information is for the other slave machines, the above-mentioned information is outputted from the interface port 3 of the other side.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a 1: N communication system in which a plurality of slave units are connected to one master unit so that the master unit and the slave units can communicate with each other. .

[0002]

2. Description of the Related Art As an interface port (connector) for connecting a computer and its terminal device to exchange data, there is an RS-232 port defined by the EIA (Electronic Industries Association). By using this RS-232 port, it is possible to connect a plurality of slave units to one master unit and to communicate between the master unit and the slave units.

FIG. 2 shows a conventional 1: N communication system in which a plurality of slave units are connected to one master unit so that the master unit and the slave units can communicate with each other. In this figure, 21 is a master unit and 22 is N slave units. Then, the master device 21 is provided with N RS-232 ports 23,
The slave unit 22 is provided with one RS-232 port 24, and the RS-232 port 23 on the master unit 21 side and the slave unit 2
Between the RS-232 port 24 on the second side, RS-232
It is connected by a communication cable 25 at a ratio of 1: 1.

[0004]

However, in the above-mentioned conventional 1: N communication system, the main unit 21 and the slave unit 2 are connected to each other.
It is necessary to provide RS-232 ports 23 equal to the number N of two, and there is a drawback that the configuration of the base device 21 becomes complicated accordingly. When the parent device 21 is installed at a position away from the group of child devices 22, N long RS-
The 232 communication cable 25 must be used, which is disadvantageous in that it is uneconomical. In addition, when communication is performed using a public line using a modem (modulator / demodulator), it is necessary to install one modem for each of the master device 21 and all the slave devices 22, and 2N modems are required for the entire system. In addition, there is a drawback that the cost for system configuration increases.

As a means for solving such a drawback, there is a communication system disclosed in Japanese Patent Laid-Open No. 62-171250. This communication method, as shown in FIG.
2 RS-232 ports 32 and 33 are provided respectively, and the wiring is crossed inside the cordless handset 31 so that a signal input / output from one RS-232 port 32 is transmitted to another RS-232 port 33. It is designed to input and output from pins. In addition, 34 is a main | base station, 35 is RS-232 port provided in the main | base station 34, 36 is each cordless handset 3
1 is an interface circuit, and 37 is a communication cable.

However, in the communication system according to the above publication, one RS-232 port 32 is for upstream side (for master side) and the other RS-232 port 33 is for downstream side (for slave side). However, there is a limitation that the master unit 34 must be installed at the most upstream end on the upstream side. Further, if the upstream port 32, the downstream port 33 and the communication cable 37 are erroneously connected, there is a disadvantage that the entire system does not operate.

The present invention has been made with the above matters in mind, and an object of the present invention is to provide an inexpensive 1: N configuration which is simple in the master unit and the slave unit and is not restricted in connection.
To provide a communication system.

[0008]

To achieve the above object, in a 1: N communication system according to the present invention, each slave unit is provided with a computer and two standard interface ports controlled by the computer. , The information with the ID code issued from the base unit to the handset is input from one interface port of the handset,
When the information is for another slave, the information is output from the other interface port.

[0009]

In the 1: N communication system having the above-described structure, when the slave unit wants to send information to the master unit, two interface ports are provided with two units by sending the same information. Any of the interface ports may be connected to the base unit side. Then, the cordless handsets can communicate with each other, and each cordless handset can start communication regardless of whether other cordless handsets are communicating or without permission from the cordless handset to communicate. You can

[0010]

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 is a diagram schematically showing a 1: N communication system according to the present invention, in which P is a master unit,
C ₁ , C ₂ , ..., C _N are slaves. Incidentally, in FIG. 1 shows only the inside of the handset C _1, the other handset C _2, for ... C _N does not show its internal structure, all handsets C _1, C _2, ... C _N The configuration of is the same.

Reference numeral 1 is a standard interface port provided on the master device P, 2 and 3 are standard interface ports provided on the slave devices C ₁ , C ₂ , ..., C _N , respectively. These interface ports 1 to 3 are: For example RS-2
32 ports. 4,5 handset C _1, C _2, ... respectively provided interface circuit to C _N, for example R
It is an S-232 interface circuit, and the slave units C ₁ and C
₂ , ... C _N are provided between the computer 6 and the interface ports 2 and 3, respectively.

[0013] 7 The interface port 1 of the master unit P most upstream slave unit C ₁ of one of the interface ports 2 and communication cable connecting, 8 of the slave unit C ₁ of the most upstream the other interface port 3 and the following A communication cable connecting one of the interface ports ₂ of the child device C ₂ and, similarly, the adjacent child devices up to the most downstream child device C _N are similarly connected by the communication cable 8.

The parent device P and the child devices C ₁ , C ₂ , ... C _N
All of the the respective is set with a unique ID code, base unit computer provided in P (not shown) and child devices C _1, C _2, ... computer provided in C _N 6
Recognizes its own ID code. And the parent machine P
An ID code is always attached to the information issued from the slave units C ₁ , C ₂ , ... C _N.

In each of the slave units C ₁ , C ₂ , ..., C _N , the information input from one interface port 2 is always input to the computer 6. Then, in the computer 6, it is confirmed whether or not the ID code attached to the information and that of the own machine match, and if they match, the information is taken in (received), or If not, the information is output from the other interface port 3.

Further, each child device C ₁ , C ₂ , ... C _N has information on the parent device P (with the ID code of the parent device P attached).
2 interface ports 2 and 3
It is configured to be able to call from any of.

The 1: N communication system configured as described above
In this case, the information transmitted from the parent device P is
Child having an ID code that matches the ID code attached to
Machine C ₁, C₂, ... C_NOnly received by. Also,
Handset C₁, C₂, ... C_NFrom the main unit P to
The same information can be sent from the interface ports 2 and 3
Then, whichever of the two interface ports 2 and 3 is the parent
Even though the machine P is connected, the master P is the slave C₁, C₂、…
C_NCan receive information from.

The computer 6 provided in each of the slaves C ₁ , C ₂ , ... C _N may be a computer for exclusively performing the above-mentioned operation, or the slaves C ₁ , C ₂ ,. _It may be for performing another operation of _N. And cordless handset C
_{Of the} two interface ports 2 and 3 provided at ₁ , C ₂ , ..., C _N , either of them may be set as the master side or the terminal side, but either one is determined in advance as the master side and the terminal side. , handset _{C 1, C 2, ... C} N when sending information to the base unit P from may be transmitted from only the master unit P side interface port 2.

In the above-mentioned 1: N communication system, inter-slave unit communication is possible. Further, when the information input to one interface port 2 in one slave is output from the other interface port 3, the information can be changed, modified, or added. As a result, even if a plurality of slaves having the same ID code are connected, information can be sent to a predetermined slave.

That is, there are four slaves with an ID code of "5", and information A from the master P for only the third slave.
When sending a message, the parent device P sends data “5”, “3”, and “A” to the first child device (ID = 5). The first handset that received this data sets the data to "5""
After changing to 2 "" A ", change this to the second cordless handset (ID =
5) is sent. And the data received 2
The first slave unit changes to "5", "1", and "A" and transmits this to the third slave unit (ID = 5). In this case, since the second digit is "1" for the third cordless handset,
Judge that this is the information for himself and take in that information. In this example, any number of slave units other than ID = 5 may be connected, and those slave units only transmit the received information as it is.

Further, the ID code of the transmitted devices P, C ₁ , C ₂ , ..., C _N is added to the information to be transmitted,
If the received devices P, C ₁ , C ₂ , ... C _N send back a reply indicating that they have been received to the sender, more reliable information communication can be performed. In this case, if there is no reply, it is retransmitted. In addition, if the received data is insufficient, or if the checksums do not match, a resend request may be made.

Further, as the ID code, a "code which all machines respond" can be used.

[0022]

The present invention constructed as described above has the following effects. Only one interface port needs to be provided on the base unit. Even if the parent machine and the child machines are separated, the child machines can be connected with a short communication cable. Even if the master unit and the slave units are separated, communication can be performed by providing a modem in the middle and using a public line or the like. In that case, one pair (two) of modems is sufficient. In particular, it is possible to send and receive information without causing a collision without using a device or a circuit for adjusting between the slaves. Both the parent device and the child device can arbitrarily send information without checking the communication status of the other device. The communication cable may be a normal RS-232 cable. Either of the two interface ports provided in the slave unit may be the master unit side or the terminal side. Therefore, it is possible to obtain an inexpensive 1: N communication system in which the configuration of the master unit and the slave unit is simple and there is no restriction in connection.

[Brief description of drawings]

FIG. 1 is a diagram schematically showing a 1: N communication system according to the present invention.

FIG. 2 is a diagram for explaining a conventional example.

FIG. 3 is a diagram for explaining another conventional example.

[Explanation of symbols]

P ... Master, C ₁ , C ₂ , ... C _N ... Slave, 2, 3 ... Interface port, 6 ... Computer.

Claims (1)

[Claims] 1. In a 1: N communication system configured to connect a plurality of slave units to one master unit and to enable communication between the master unit and the slave units, each of the slave units. In addition, a computer and two standard interface ports controlled by this computer are provided, and the information attached with the ID code issued from the master unit to the slave unit is
A 1: N communication system, characterized in that when input from one interface port of a slave unit and when the information is for another slave unit, the information is output from the other interface port.