JPS61131643A - Node of interface bus - Google Patents

Abstract

PURPOSE:To attain ease of change for system constitution of devices by comparing an interface clear signal transmitted from other node with an interface clear signal outputted from the own device to decide the operating mode of the said mode. CONSTITUTION:An inter-node transmission control section 1 receives a signal RS and transmits a signal SS processed in a node N to an outgoing node. When an interface clear signal from a device connected to the own interface bus (b), bus management information from the own device is outputted to the internode transmission control section 1 by an interface bus receiver 3. A node operation mode control section 4 compares the interface clear signal outputted from a specific node with the interface clear signal received from the own interface bus to decide the operating mode of the node N.

Description

[Detailed Description of the Invention] <Industrial Application Field> The present invention is applicable to extending the length of an interface bus such as 6GP-IS, which interconnects multiple devices such as computers, voltmeters, and printers. The present invention relates to the node used, and particularly to i-control for switching the operation mode between a specific mode and a general mode in this node.

<Prior Art> A system using an interface bus as shown in FIG. 3 is common in order to exchange information between a plurality of devices such as computers, voltmeters, and printers.

In this figure, 01-G5 are the calculator and voltmeter.

Devices such as printers, b I-b a is the interface bus connected to devices G, ~G5, Q is devices G1 ~ G5
This is a connector that connects the interface buses b+ to b4. In such a system, one of the devices G1 to G5 (for example, device G+) has a system controller that initializes the interface bus, and a controller that specifies the functions of each device (talker, listener, etc.). IIIgl: The receiver operates as a system controller and controller with interface bus B.
,~b4 and machine! l Controls information exchange between G2 to G5.

However, for an interface bus such as GP-IB that connects multiple devices, the length and number of cables are limited depending on the number of devices. Interface bus extent systems using such nodes and cables are known.

In this figure, N+ to N4 are nodes connected to the interface buses b1 to b4 of each i-device, and C is a node N1.
The device G + "Ga" connected to ~N4 on the interface buses b1 to b4 is a cable that is a serial transmission path for dark information exchange, and the part E surrounded by the dotted line is an extent system that extends the interface bus.

Although this figure shows a system in which one device is connected to each of the nodes N1 to N4, it is also possible to connect a plurality of devices to one node.

In such a system, like the system shown in FIG. 3, one of the devices G+ to G4 acts as a system controller and controls the extent system and information exchange between the devices.

In the system shown in FIG. 4, for example, the II unit G+ serves as a system controller and a controller.

In this case, the node NI in the bus extent system E is set as a specific node (specific mode),
The other nodes N2 to N4 are set as general nodes (general mode).

First, device G uses an interface to initialize each interface bus in this extent system E.
7. Outputs the eighth clear signal IFC-1 onto the interface bus b, and the node N+ broadcasts this signal IFC=1 to other nodes N2 to N4, and the other devices 02 to G4 that receive this signal IFC=1. outputs the signal IFC-1 on its own interface buses b2 to b4, and initializes the interface buses of the connected devices.

next,! 1! The device G1 sends a remote/local switching signal REN to each device 02 to G4, and indicates whether the information on the data in the interface bus is an interface message for interface bus III or device data or message. Signal A indicating whether
Management information such as TN is announced via node N1.

On the other hand, the other devices G2 to G4 that have received this management information individually control and transmit No. 18 5RQ-1 requesting service from the device G1 to the respective nodes N2 to N4.
The device GI receives this signal 5RQ-1 and performs corresponding processing.

In this manner, in the extent system E of the interface buses b1 to b4, a signal from one system controller/controller device Q1 is transmitted to a specific node N.
+, is transmitted to the devices G2-G4 via the cable C1 general nodes N2-Na, and the devices 01-G4 exchange information.

However, in this conventional interface bus extent system, a specific 11151 unit operates as a system controller and a controller, and the transmission direction of signals such as bus IF management information is fixed, so each time the system configuration is changed, the device and This eliminates the tedious task of changing the settings of each node, and configuring a system where devices connected to other nodes automatically start backing up if the device that serves as the system controller/controller goes down. It had the disadvantage of not being able to do so.

<Problems to be Solved by the Invention> The problems to be solved by the present invention are to provide an interface that allows a connected device to function as a system controller and a controller without changing the hardware settings of the device, etc. The goal is to realize the bus node.

<Means for solving the problem> In order to solve the above-mentioned problem, in the present invention,
It receives interface clear signals sent from other nodes, and also receives interface clear signals output from its own connected devices, and compares them to determine the operating mode of that node. Configured interface bus nodes.

That is, the configuration of the present invention is as follows.

An interface bus node installed on a cable extending the interface bus connected to each of multiple devices includes an inter-node transmission control unit that receives information from the upstream node and transmits information to the downstream node, and other nodes. an interface bus driver that transmits an Inter-7Ace clear signal and bus management information received from a node to the inter-node transmission control unit to a device via an interface bus connected to the node; and a device connected to the interface bus. an interface bus receiver that outputs the interface clear signal and bus management information from the device to the inter-node transmission control unit when an interface clear signal is issued from the device; and an interface bus receiver that outputs the interface clear signal from the other node and the bus management information from the device; The node of the interface bus is characterized by comprising a node operation mode control section that controls switching of the operation mode of the node between a general mode and a specific mode by comparing the node with a clear signal.

Effect〉 The arrangement of the present invention operates as follows.

When the inter-node transmission control unit receives the interface clear signal rFc-1 transmitted from a node in a specific operation mode connected to the system controller/controller, this signal is sent to the node operation mode control unit,
This node functions as a general mode of operation node.

In addition, the node operation mode 1ilJ ti section is connected to this node after a certain period of time has passed after the Inter-7 eighth clear signal IFC received from another specific node switches from "1°" to "Pa0". Interface clear signal 111 I from the interface bus
If t is received, it is interpreted that an interface clear signal has been sent from a device connected to this node, and the node is operated to function from the general mode to the specific mode.

If this node receives an interface clear signal rFC=1 from another device in the specific node state, it switches from the specific mode to a general node.

<Embodiment> An embodiment of an interface bus node according to the present invention is shown in FIG.

In this figure, N is a node according to the invention and RX
is an inter-node transmission receiving section that regenerates the serial signal from the upstream node via an optical fiber or coaxial cable, and outputs the signal R8, and TX converts the level of the signal SS from the inter-node transmission control section 1. optical fiber to the downstream node,
1 is an inter-node transmission control section that receives the signal R8 and transmits the signal SS processed in the node N to the downstream node; 2 is an inter-node transmission transmitter that transmits data via a coaxial cable, etc. an interface bus driver 3 that receives upstream node information (signal R8> from the transmission control unit 1) and outputs the signal to its own interface bus b;
4 is an interface bus receiver that outputs bus management information from its own Ill device to the inter-node transmission control unit 1 when an interface clear signal is issued from a device connected to its own interface bus b; 4 is a specific node; Input and compare the interface clear signal rFcbcd published by IFC and the interface clear signal ■FCbc/rsp received from its own interface bus, and instruct other nodes to detect the interface clear signal IFCs.
The node operation mode control section 5 determines the operation mode of this node N by d, and 5 transmits a signal 5RQsd between nodes requesting a service from another node to the controller device when this node N enters a specific mode. This is a second interface bus driver that receives data from the N controller 1 and outputs it to its own interface bus b.

The operation of the node thus configured and the transmission and reception of signals according to the present invention are as shown in the flowchart shown in FIG.

Next, a detailed explanation will be given using FIG. 1.2.

When the power is turned on, the node operation mode control section 4 sends an interface clear signal I F Cb c / received from its own interface bus b to the inter-node transmission control section 1.
τsp, remote/local signal RENb c, message signal ATNbc, which is an instruction signal that can be broadcast to other two-tots BC = O1 When this node N becomes a specific node, interface clear signal IFCsd of the standard interface bus of another node and service request Signal 5RQ
Signal 5N that instructs to detect and report the state of sci
S=O, and this node N functions as a general node.

When this node N operates as a general node, the interface clear signal IFCbe from the specific node is
d is sent via interface bus driver 2 by connector Q to interface bus b, which is cleared. Further, the remote/local signal RENbcd and message signal ATNbcd from the specific node are transmitted from the inter-node transmission control unit 1 to the interface bus driver 2, and output from the connector Q to its own interface bus b. At the same time, the remote/local signal RENbed and the message signal ATNbcd are transmitted from the inter-node transmission control unit 1 to the downstream node by the inter-node transmission transmitting unit TX.

On the other hand, a service request (g
When the signal 5RQ=1 is output, the SRQ signal of the interface bus b is output to the interface receiver 3, and further sent to the inter-node transmission control unit 1 as service request signal detection information 5RQrsp, and sent to the inter-node transmission transmission section. The signal is sent by X to the system controller and controller device as a response signal to the detection report instruction.

Next, when a device connected to this node N replaces the current system controller/controller and becomes a system controller/controller, this device issues an interface clear signal IFC=1.

The interface bus receiver 3 sets this interface clear signal [FC to signal IFCbc/rsp=1, and responds to the current detection report instruction signal from the specific node.
This signal IFCbc/l'sp is sent to the node circle transmission control section 1 as a response signal from the node N, and at the same time, this signal IFCbc/l'sp is sent to the node operation mode control section 4.

The node operation mode control unit 4 controls the interface clear signal IFCbed from the specific node while it is not output to its own interface bus (IFCbcd=O
), the signal IFCb is sent from its own interface bus b.
When c/rsp=1 is received for more than a time and the inter-node transmission control unit 1 issues a signal CHAV indicating that the line can be advertised and detected by the inter-7 eighth clear signal IFC, this node N is set to a specific mode. (1), and the device connected to this node serves as a system controller.

Next, a public information instruction signal B is sent to the inter-node transmission control unit 1.
Output C-1. Then, node N receives remote/local signal R from the device via interface bus b.
EN and the message signal ΔTN are given to the interface bus receiver 3, and the signal RENbc and the signal ATNb c
Inter-node transmission - These signals are transmitted to other nodes via the control unit 1.

That is, ((IFCbc /rspha1Fcbcd)>t>1-
Under the conditions of XCHAv, this node N is a specific node (specific mode (
1)).

Next, when the interface clear signal rFC from its own interface bus b changes from "'1" to O, the node operation mode control unit 4 outputs the signal IFCbc/rs.
p = O (condition IFCbc/τSp) is detected and a signal 5NS-1 for detecting a signal from another node is output to the inter-node transmission control unit 1, and this node N is set to the specific mode (2).
The state changes from the signal publicity state to the other node signal detection state.

Here, if another node outputs the service request signal 5RQ=1, this node N outputs the inter-node transmission control unit 1.
This service request signal is received as a signal 5RQsd, and this signal 5RQsd is transmitted to the second interface driver 5, and is applied from this node N to the device via the interface bus b.

Also, when the interface clear signal IFC from its own device changes from "O'° to "1", (I
FCbc /rgp-1), this node N returns to the specific mode (1) again and repeats the same operation as described above.

In the detection state of specific mode (2), if another node outputs the interface clear signal IFC=1 in order to function as a system controller and controller, and this node N detects the signal IFC=1, the inter-node The interface clear signal rFc-1 of the other node is received from the transmission 1IIIi1 section 1 by the node operation mode control section 4 as the signal IFCsd=1.

At the time when this signal IFCsd is given, the node operation mode control unit 4 outputs the public information signal BC=O1 and the detection signal 5N.
S-0, the signal line (line) of the interface bus is opened, and this node N is made to function as a general node.

In this way, this node N can switch and function as a specific node or a general node depending on signals from other nodes.

<Effects of the Invention> As described above, according to the present invention, in a node of an extent system of an interface bus, the operation mode of the node can be controlled to be switched to a specific mode or a general node by a signal from another node. Therefore, there is no need to change the hardware settings every time the system configuration of the device is changed.Also, even if the system controller/controller device goes down, if this is detected, the connection will be restarted. By switching the operation mode of the existing node, its own device starts operating as a system controller and controller, and a backup system can be automatically configured.

[Brief explanation of drawings]

1 is a block diagram of nodes of an interface bus according to an embodiment of the present invention; FIG. 2 is a 70-chart showing switching conditions of nodes of an interface bus according to an embodiment of the present invention; and FIG. 3 is a block diagram of nodes of an interface bus according to an embodiment of the present invention. Figure 4 is a diagram of an extent system for extending an interface bus connected to equipment. DESCRIPTION OF SYMBOLS 1... Inter-node transmission control unit, 2... Interface bus driver, 3... Interface bus receiver, 4... Node operation mode control unit, 5... Second interface bus driver, G, G
l~G5...Equipment, E...Extent system, N, N blind~N4...Node, b...Interface bus, 9...Connector, RX...Receiving section for inter-node transmission, TX: Transmission unit for inter-node transmission. Figure 3 Figure 4

Claims (1)

[Claims] (1) In an interface bus node installed on a cable that extends the interface bus connected to each of multiple devices, an inter-node transmission control unit that receives information from an upstream node and transmits information to a downstream node. an interface bus driver that transmits an interface clear signal and bus management information received by the inter-node transmission control unit from another node to a device via an interface bus connected to the node; and an interface bus driver connected to the interface bus. When an interface clear signal is issued from a device, an interface bus receiver outputs this interface clear signal and bus management information from the device to the inter-node transmission control section; 1. A node of an interface bus, comprising: a node operation mode control unit that controls switching of the operation mode of the node between a general node and a specific mode by comparing the node with an interface clear signal.