JPH02296430A - Local area network equipment - Google Patents

Abstract

PURPOSE:To prevent production of an address setting error in a system in which reconnection takes place frequently by setting an address to a branch means from a bus to an information processing unit and using the information processing unit connecting to the address. CONSTITUTION:A branching means has an address setting switch 6 and an information processing unit has a receiver circuit 10 reading a station number. The control circuit system is a system using a general-purpose control circuit 15 as a master station and terminal equipments 16, 17 as slave stations, and the communication among the general-purpose computer 15 and the terminal equipments 16, 17 is implemented. Moreover, an address on a network is set to branching filters 20-25 and 28. When the job such as program development is in operation in the system, the communication is initiated in response to the opening of a session from all terminal equipments. Thus, it is not required to fix the address on the network and the user attains the job even when any branching filter connects to the terminal equipment.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention is applied to a C5MA/CD or C3MA bus-type local area network.

In particular, the present invention relates to address setting means in a network for an information processing device connected to the network.

〔overview〕

In a C3MA/CD or C3MA type local area network, the present invention sets an address in the branching means from the bus to the information processing device, and the connected information processing device uses this address, thereby preventing frequent connection changes. This system is designed to prevent address setting errors from occurring even in systems that are used in

[Conventional technology]

A conventional example of this type of local area network is
Network specified by IEB8802.3 and NEC Corporation's tlRANcH4670 and 13RA1
lIfl') 14680 network, etc.

[Problem that the invention seeks to solve]

In such conventional local area networks, the network addresses of information processing devices such as general-purpose computers and terminal devices connected to the network are set in the hardware of each information processing device, or are set in software configuration information. In a conventional environment where each terminal device was installed in a fixed manner, if an address was set for each terminal device at the time of network establishment, there would be little need to change the address thereafter, and problems related to addresses would occur when operating the network system. However, with the recent development of mobile terminal devices and portable personal computers that serve as terminal devices, terminal devices are frequently moved and terminal devices used in other network systems are easily brought in. Currently, if an address is set for each terminal as in the conventional example, there is a high probability that an address setting error will occur at the terminal, and there is a drawback that serious troubles are likely to occur in network system operation.

The present invention aims to eliminate such drawbacks, and aims to provide a local area network device that can prevent address setting errors of connected terminals from occurring.

[Means for solving problems]

The present invention includes a plurality of stations including a branching means inserted into a transmission bus and an information processing device connected to the branching means, and furthermore, each of the stations is configured to allow other stations to communicate via the transmission bus. In the local area network device, the branching means includes a means for determining whether or not the station is transmitting by detecting a carrier wave on the transmission bus, and permitting or temporarily prohibiting transmission of the own station based on the determination result. comprising a setting means for setting the station number of the own means occupying the transmission bus,
The information processing device is characterized in that the information processing device includes a readout device that reads out the station number set in the setting device of the branching device to which the information processing device is connected.

[Effect]

The address information set in the branching means is sent to the information processing device via the transmission means between the branching means for branching the bus signal from the transmission bus of the local area network to the information processing device and the information processing device connected to this branching means. Read it with .

In this way, by setting the local area network address of the information processing device in the branching means, operation can be started immediately even if the terminal is moved and connected.

〔Example〕

An embodiment of the present invention will be described below with reference to the drawings. FIG. 2 is a block diagram showing the configuration of this embodiment.

As shown in FIG. 2, this embodiment is a signal transmission bus that is the main line of a bus type local area network, and electrically consists of transmission lines 3 and 4, which are one transmission line, and this transmission line 3. and 4, and includes a branching device 1 that branches signals (bus signals) on a transmission path to the information processing device, and a terminal 2. Here, the branching device 1 has a branching circuit 5 that branches a bus signal, and a branching circuit 5 that branches a bus signal. The branching device 1 and the terminal 2 are provided with an address setting switch 6 for setting the address on the network of the terminal 2 connected to the device 1, a signal path 9 for branching and transmitting bus signals, and a signal path 9 for setting the address setting switch 6. It is connected by a signal path 8 for transmitting information and a ground signal line 7.

FIG. 3 is a diagram illustrating the embodiment shown in FIG. 2 in more detail, and the address setting switch 6 of the branch 1 is composed of a group of individual switches sw, , sw2, SW, , ) SWo, This switch sw, , sw2,
One end of swn, , sw is connected to the ground signal line 7, and the other end is connected to each signal line forming the signal path 8. The signal lines constituting this signal path 8 are connected to pull-up resistors R, , R2RI%l and Rn at the terminal 2, respectively, and the receiver circuit 10.
It becomes logic "1" or logic "0" according to the opening/closing of switches SW1 to SW7, and constitutes address information. Further, the output of the receiver circuit 10 is connected to the internal bus of the terminal 2 by a signal group 12, and the control section of the terminal 2 (not shown) reads out the setting state of the address setting switch 6 to the receiver circuit 10 via a signal line 14. The address information set by the address setting switch 6 can be read out.

That is, this embodiment includes a plurality of stations including a branching device 1, which is a branching means inserted into a transmission bus, and a terminal 2, which is an information processing device connected to this branching means. is equipped with a means to determine whether or not another station is transmitting via this transmission bus by detecting the carrier wave on this transmission bus, and to permit or temporarily prohibit transmission of the own station based on the result of this determination. Further, as a feature of the present invention, the branching means includes an address setting switch 6 which is a setting means for setting the station number of the top means occupying the transmission bus, and the information processing apparatus It has a receiver circuit IO which is a readout means for reading out the station number set in the setting means of the connected branching means.

FIG. 1 is a diagram showing the configuration of a data communication system to which this embodiment is applied.
A general-purpose computer 15 and terminals 16 and 17 are connected to a network constituted by transmission lines 1, 22, 23, 24, 25 and 26, and transmission lines corresponding to transmission lines 3 and 4 shown in FIG. This communication system is a system in which the general-purpose computer 15 is the main station and the terminals 16 and 17 are slave stations. is not performed. Further, addresses on the network are uniquely set to the branchers 20, 21, 22, 23, 24, 25 and 26. When operations such as program development are performed using such a data communication system, the main station, general-purpose computer 1, is used.
5 does not actively output a specific message to a specific terminal, and communication starts in response to the session opening from the terminal, so there is no need for each user to fix the address on the network, and the user You can connect your terminal to any branch and still be able to perform your business.

〔Effect of the invention〕

As explained above, according to the present invention, the address setting of the local area network system is performed at the branch switch, and a data communication system is obtained in which the address is uniquely set for each branch switch, regardless of the hardware and software settings of the terminal etc. This has the effect of centralizing address management in the network and preventing troubles caused by incorrect address settings. In addition, for the user, if the address of the general-purpose computer is constant, the own address is set by the branch and can be read every time, so even if the terminal is moved and connected to another branch, operation will start immediately. This has the advantage of being able to connect terminals used in other network systems operated in a similar manner.

■... Branch, 2... Terminal, 3.4... Transmission line,
5... Branch circuit, 6... Address setting switch, 7
...Ground signal line, 8.9...Signal path, 10...Receiver circuit, 12...Signal group, 14...Signal, 15
... General-purpose computer, 16.17 ... Terminal, 18.19
... Termination, 20.21.22.23.24.25.2
6-... Turnout, SW, , SW2 , SW, -, ,
SW.

...Switch, Rl, R2, Rr+-1, Rh...
・Pull-up resistor.

Claims (1)

[Scope of Claims] 1. A plurality of stations including a branching means inserted into a transmission bus and an information processing device connected to the branching means, and each of the stations is configured to allow other stations to use the transmission bus. In a local area network device that is equipped with means for detecting carrier waves on this transmission bus to determine whether transmission is being transmitted via the transmission bus, and permitting or temporarily prohibiting transmission from the own station based on the result of this determination, the above-mentioned The branching means has a setting means for setting the station number of the own means occupying the transmission bus, and the information processing device reads out the station number set in the setting means of the branching means to which the own device is connected. A local area network device comprising: means.