JPS60260251A - Spread control system in annular communication system - Google Patents

Abstract

PURPOSE:To ensure the communication between slave nodes by transmitting various signals as they are when a signal control supervisory section detects the function stop of a signal control section. CONSTITUTION:A signal arriving from a transmission line 3 is decomposed into communication lines B1-Bm and a signal line D by a frame decomposing section 42, data (B) transmitted by the communication lines B1-Bm is transmitted to a switch section 44 and a control signal (d) attained by the transmission line D is transmitted to a signal control section 45. A frame assembling section 46 assembles the data (b) and the control signal (d) based on the clock signal from the clock generating section 43, adds a frame signal and transmits the result to the transmission line 3. A signal control supervisory section 48 makes a by-pass switch dsw1 conductive when a reset signal (r) reaches the transmission stop, transmits the decomposed data (b) and the control signal (d) to a frame assembling section 46 as they are and transmits various signals reached from the transmission line 3 to the transmission line 3 in the same form.

Description

Detailed Description of the Invention (a) Technical Field of the Invention The present invention relates to a ring communication system, and in particular to a distributed control system in a ring communication system that enables communication between slave nodes even when a master node is affected. (b) Background of the technology In recent years, ring communication systems have become popular, in which a plurality of terminals located within a business office etc. are connected in cascade through a ring transmission line, and they are able to communicate with each other via the transmission line. be.

(C1 Prior Art and Problems FIG. 1 is a diagram showing an example of a ring communication system to which the present invention is applied, FIG. 2 is a diagram showing a multiplexed configuration of the transmission path in FIG. 1, and FIG. The figure is a diagram showing an example of a conventional communication system. In Figure 1, a ring communication system includes one main node 1 and n slave nodes 2-1 to 'l-
The main node 1 and the slave nodes 2-1 to 2-n are connected in series in a circular manner. Transmission line 3
As shown in FIG. 2, at every predetermined period T, a frame signal F and m communication paths B1 and Bm used for data transmission between the main node l and the slave nodes 2-1 to 2-1 are transmitted. ,
It is time-division multiplexed using a control signal d that is commonly used for transmitting various control signals that control the data transmission.

Note that F is a frame signal and T is a period (for example, 125 microseconds).

Note that the communication direction in the transmission path 3 is all clockwise.

In FIG. 3, when the slave node 2-1 desires to communicate with the slave node 2-2, the slave node 2-1 sends a communication request signal d1 indicating a communication request to the slave node 2-2 through the signal path. It is sent to the main node l via. Communication request signal d
1 connects to the main node 1 via slave nodes 2-2 to 2-n.
transmitted to. Main node 1 that received the communication request signal d1
sends a communication interval signal d2, which determines whether communication with the slave node 2-1 is possible or not, to the slave node 2-2 via the signal path. The communication interval signal d2 is transmitted to the slave node 2-2 via the slave node 2-1. The slave node 2-2, which has received the communication interval signal d2, sends a communication confirmation signal d3 to the main node 1 via the signal path if it is in a communicable state.

The communication confirmation signal d3 is transmitted to the main node 1 via slave nodes 2-3 (not shown) to 'l-n. The main node 1 that received the communication confirmation signal d3 connects the communication paths B1 to B.
Two free communication paths (for example, Bl and B2) from m are secured for communication between slave nodes 2-1 and 2-2, and communication path B1 is set as a transmission path and communication path for slave node 2-1. Road B
The slave node, 2-
A communication path instruction signal d4'' is sent to slave node 2 via the signal path, giving an instruction to start communication using communication path B2 as a transmission path and communication path B1 as a reception path. -1, and the communication path instruction signal d4' is the slave node 2.
-1 to the slave node 2-2.

The slave node 2-1 that received the communication path instruction signal d4 sends data b1 addressed to the slave node 2-2 via the communication path B1, and the slave node 2-2 that received the communication path instruction signal d4' starts communication. Data b1 transmitted via path B1 is received. Also, slave node 2-2 receives data b2 addressed to slave node 2-1.
) The data b2 is transmitted via the communication path B2, and the slave node 2-1 receives the data b2 transmitted via the communication path B2.

As is clear from the above description, in a conventional ring communication system, all communication between slave nodes 2-1 to 2-n was controlled by the master node 1. Therefore, if the master node 1 stops the above-mentioned control function due to a failure etc.
There was a drawback that all communications between slave nodes 2-1 to 2-n were paralyzed.

(d) Purpose of the Invention The purpose of the present invention is to eliminate the drawbacks of the conventional ring communication system as described above, and to realize a means that can ensure communication between slave nodes even if the master node stops functioning. There is a particular thing.

(e) Structure of the invention This object has a main node, a plurality of slave nodes, and one or more communication paths that cascade the master node and each slave node in a circular manner and transmit required data in one direction. In a ring communication system composed of transmission paths, the main node and each slave node identify whether the communication channel is empty or blocked, and send data destined for the required master node or slave node via the free communication channel. a first means; a second means for selecting and receiving data addressed to the node from among the data arriving from the communication path; This is achieved by providing a third means for transmitting data arriving from a communication channel to its preferred communication channel.

In other words, in the present invention, each slave node can also select an available communication channel and communicate without being controlled by the master node, and the master node is also able to communicate without being controlled by the master node, and even if the master node stops functioning, the data transmitted through the communication channel is not affected. Transfer without giving. Therefore, even if the master node is affected, communication between slave nodes is ensured.

(fl　Embodiments of the invention An embodiment of the present invention will be described below with reference to the drawings.

FIG. 4 is a diagram showing the configuration of a master node and a slave node according to an embodiment of the present invention. Note that the same reference numerals indicate the same objects throughout the figures. The configuration of the target ring communication system is shown in Figure 1, and the multiplex configuration of the transmission line 3 is shown in Figure 2.
Figure. In FIG. 1, the main node 1 and each machine node 2-1 to 2-n each have a configuration as shown in FIG. In FIG. 4, the signal arriving from transmission line 3 is
It is transmitted to the frame decomposition unit 42 via the reception unit 41.

The frame decomposition unit 42 separates the communication paths B1 to Bm and the signal path from the signals arriving from the transmission path 3 based on the clock signal supplied from the clock generation unit 43, and separates the data b transmitted by the communication paths B1 to Bm. is switch part 4
control signal d transmitted to 4 and also transmitted by the signal path.
is transmitted to the signal control section 45. As in the conventional main node 1, the signal control unit 45 controls the frame decomposition unit 42.
a function of analyzing the control signal d transmitted from the frame assembly unit 46, a function of generating the required control signal d and transmitting it to the frame assembly unit 46;
It has a function of managing the empty state of the communication paths B1 to Bm and a function of controlling the settings of the switch section 44. The frame assembling section 46 assembles the data b transmitted from the switch section 44 and the control signal d transmitted from the signal control section 45 based on the clock signal supplied from the clock generation section 43, and further adds a frame signal F. , and sent to the transmission path 3 via the transmitter 47. Furthermore, when the signal control section 45 is normally executing the above-mentioned functions, it transmits a reset signal r to the signal control monitoring section 4B at regular intervals. The signal control monitoring unit 4B determines that the signal control unit 45 is functioning normally while the reset signal r is being transmitted at regular intervals, and sets the bypass switch dswl to the blocked state and switches the bypass switch dswl to the blocked state. Switch dsw2 is set to conductive state. When the signal control unit 45 stops the above-mentioned function, it outputs a reset signal r.
Stop sending. The signal control monitoring section 48 receives a reset signal r.
When the signal controller 45 stops, the signal control unit 45 determines that the function has stopped, turns the bypass switch dswl into a conductive state, puts the bypass switch dsw2 into a blocked state, and switches the switch unit 44 into a conductive state.
connects the frame disassembly section 42 and frame assembly section 46. As a result, the data b decomposed by the frame decomposition unit 42 is transferred to the frame assembly unit 4 via the switch unit 44.
6, and the control signal d is also transmitted to the bypass switch dswl
The signal is transmitted to the main frame assembly section 46 via the main frame assembly section 46. Therefore, various signals arriving at the receiving section 4I from the transmission path 3 are sent out from the transmitting section 47 to the transmission path 3 in the same format.

As is clear from the above description, according to this embodiment, each of the machine nodes 2-1 to 2-n also has a communication path B in the same way as the main node 1.
The main node 1 and each machine node 2-1 to 2-n are equipped with an air blockage management function of 1 to Bm, and each of the main node 1 and each aircraft node 2-1 to 2-n performs transmission control when the signal control monitoring unit 48 detects that the signal control unit 450 has stopped functioning. Since various signals transmitted through the path 3 are transferred sideways, communication between the slave nodes 2-1 to 2-n is ensured even if the temporary master node 1 stops functioning due to a failure or the like.

It should be noted that FIG. 4 is only one embodiment of the present invention, and for example, the configurations of the main node 1 and the slave nodes 2-1 to 2-n are not limited to those shown in the figure, and there may be many other configurations. However, the effects of the present invention do not change in any case. It goes without saying that the configuration of the ring communication system to which the present invention is applied is not limited to that shown in the drawings.

(gl) Effects of the Invention According to the present invention, even if the main node stops functioning in the ring communication system, communication between slave nodes is ensured, and reliability and availability of the ring communication system are improved. will improve.

[Brief explanation of the drawing]

FIG. 1 is a diagram showing an example of a ring communication system to which the present invention is applied, FIG. 2 is a diagram showing a multiplexed configuration of the transmission path in FIG. 1, and FIG. 3 is a diagram showing an example of a conventional communication system. , FIG. 4 is a diagram showing the configuration of a master node and a slave node according to an embodiment of the present invention. In the figure, 1 is a main node, 2-1 to 2-n are slave nodes, 3 is a transmission path, 41 is a receiving section, 42 is a frame disassembly section, 43 is a clock generation section, 44 is a switch section, and 45 is a signal control section. section, 46 is a frame assembly section, 47 is a transmitting section, 48
is the signal control monitoring section, b, bl and b2 are data, B1
~Bm is a communication path, D is a signal path, d is a control signal, dl is a communication request signal, d2 is a communication interval signal, d3 is a communication confirmation signal, d4 and a41 are communication path instruction signals, dswl and dsw2 are side signals. F is a frame signal, r is a reset signal, and T is a period. Folding 21!1 dice 3 concave '44 圀

Claims (1)

[Claims] In a ring communication system consisting of a main node, a plurality of slave nodes, and a transmission path having one or more communication paths that cascade the master node and each slave node in a ring and transmit required data in one direction. , a first means for identifying an empty/blocked state of the communication path to the main node and each slave node, and transmitting data destined for the desired master node or slave node via the free communication channel; a second means for selecting and receiving data addressed to the own node from the arriving data; and a second means for selecting and receiving data addressed to the own node from among the arriving data; 1. A distributed control method in a ring communication system, characterized in that a third means for transmitting data to a network is provided.