JPH08223612A - Communication line switching system - Google Patents

Abstract

PURPOSE: To reduce the burden of a software and to shorten the time of communication interruption caused by switching by defining either transmission or reception as a basic layer and defining the result, for which only the signal polarities of input and output are stitched in the same order as the arrangement of input signal sequence and output signal sequence in that layer, as the arrangement of input and output signal sequences in the other layer. CONSTITUTION: This system is composed of a transmission system matrix switch 13 having 4×2 constitution composed of four systems of input signal sequences and two systems of output signal sequences in a transmission system and a reception system matrix switch 16 having 2×4 constitution. The transmission system matrix switch 13 selects one signal from fourinput signal sequence terminals 1-4 while using two four-input/one-output selector circuits 14 and 15 and outputs that signal to output signal sequence terminals 5 and 6. On the other hand, since the constitution of the reception system matrix switch 16 is inverted in comparison with that of the transmission system matrix switch 13, this matrix switch 16 can be composed of four pieces of two-input/one-output selector circuits 17-20. At such a time, the arrangement of input and output sequences is made equal with the transmission system and only the signal polarities of input and output are switched.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a point-to-point system for switching a plurality of communication control lines.

[0002]

2. Description of the Related Art Generally, as a form of a transmission network, from a one-to-one transmission system between two points (point-to-point system), a local area in which one transmission line is shared by a plurality of systems -There are various types up to the network system (LAN system). If the network is configured by the LAN system, the circuit in the LAN interface part becomes complicated and the communication protocol becomes complicated, so that it is not often adopted in a small-scale system. For this reason, the point-to-point method is the mainstream, and switching of nodes is performed by matrix switches. FIG. 2 shows a basic matrix switch 13 and a circuit 22 for controlling it.
26 is shown. In FIG. 2, a matrix switch 1 having a 4 × 2 configuration having four systems of input columns 1 to 4 and two systems of output columns 5 and 6
This will be explained in Section 3. Input columns 1 to 4 are matrix switches 1
A signal having a predetermined input number is selected by the selector circuits 14 and 15 which are the constituent elements of No. 3, and are output to the output column 5 and the output column 6.

Next, a circuit for controlling the selector circuits 14 and 15 will be described. The setting state of the matrix switch 13 is externally given to the microcomputer 22 via the communication port 21. Based on this, the input column register 24 that holds the states of the input columns 1 to 4 and the output register 2 that holds the states of the output columns 5 and 6 connected by the data bus
5, the address bus is decoded by the decoder 23 to generate a strobe signal, and each data is held in each register. Next, in the crosspoint register 26, these data are stored in the strobe signal from the decoder 23 as the input signal number for each output column. A more detailed description will be given with reference to FIG. The matrix switch 13 is composed of four-input, one-output selector circuits 14 and 15. The four input signal trains 1 to 4 are commonly input to the two sets of selector circuits 14 and 15, and the respective outputs are selected according to the matrix setting state to become the output trains 5 and 6.

Next, the control circuit will be described. The value of the input string register 24 is the value of the two sets of crosspoint registers 2
It is commonly input to 8 and 29. The value set in the output column register 25 is decoded by the decoder 27 into two control lines, which are connected to the enable terminals of the crosspoint registers 28 and 29, respectively. Next, the strobe signal from the microcomputer 22 is input to the cross point registers 28 and 29, and the number of the input string for the predetermined output string is stored. This operation is set for all output columns. FIG. 4 shows a flow of setting the crosspoint register. In order from the first output column, the three items of output column, input column, and crosspoint register are set until the maximum number of output columns is reached. In the above description, only one system of the communication line has been described, but since the system actually has two systems of the transmission system and the reception system, the circuit scale is doubled. Also, the burden on the software increases.

[0005]

In the above-mentioned prior art,
Due to the bidirectional nature of the communication line, separate matrix switches are required for the transmission and reception systems, and two control circuits are required accordingly. Furthermore, software is also required to be designed for each system. It is an object of the present invention to eliminate these drawbacks and to provide a communication line switching system in which even if the matrix switch layer has two layers of transmission and reception, it can be managed as one layer on software.

[0006]

In order to achieve the above object, the present invention uses either transmission or reception as a basic layer, and inputs and outputs signals in the same order as the arrangement of input signal sequences and output signal sequences in that layer. The input and output signal trains in the other layer are arranged by exchanging only the output signal polarities. Then, the input signal string register and the output signal string register in the base layer are commonly used in the other layer, and in this layer, the input signal string register is used as the output signal string register and the output signal register is used as the input signal string register. It was done.

[0007]

As a result, the number of registers can be halved, and the structure can be further managed by software. Therefore, not only the load on software can be reduced, but also the time required for switching the matrix switch can be reduced. It can be done in about half compared to the conventional method.

[0008]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to FIG. In FIG. 1, a transmission system matrix switch 13 having a 4 × 2 configuration of four input signal trains and two output signal trains for the transmission system.
2 is a configuration of the reception system matrix switch 16 having a 2 × 4 configuration. The transmission system matrix switch 13 selects one signal from four sets of input signal string terminals 1 to 4 by two sets of four-input and one-output selector circuits 14 and 15 and outputs it to the output signal string terminals 5 and 6. . One of the reception system matrix switches 16 has an input / output configuration opposite to that of the transmission system matrix switch 13, and thus can be configured by four sets of 2-input and 1-output selector circuits 17 to 20. At this time, the arrangement of the input and output columns is in the same order as in the transmission system, and only the input and output signal polarities are switched.

That is, the first output signal train of the transmission system is the output signal train terminal 5, the second is the terminal 6, and the first to fourth input signal trains are assigned to the terminals 1, 2, 3, and 4, respectively. At this time, the first input signal sequence of the receiving system is arranged at the terminal 7, the second is arranged at the terminal 8, and the first to fourth output signal sequences are arranged at the terminals 9, 10, 11, 12 respectively. With this arrangement, the receiving system can be automatically set only by setting the transmitting system matrix switch 13. Specifically, when setting the fourth terminal 4 as the input signal string and the first terminal 5 as the output signal string in the transmission system,
In the receiving system, it is necessary to set the first terminal 7 of the input signal sequence and the fourth terminal 12 as the output signal sequence, but since the input / output sequence of the receiving system is arranged according to the above rules, the transmission system The input / output signal train of the receiving system can be set only by exchanging the output signal train and the input signal train of.

Next, the control circuit will be described. The control circuit externally gives the setting state of the matrix switch to the microcomputer 22 via the communication port 21.
Based on this information, the input column register 24 and the output column register 25 connected by the data bus are set. In this setting, the decoder 23 connected to the microcomputer 22 via the address bus outputs strobe signals at predetermined addresses, and this is used as a clock.
Holds each register data. Next, the data of these input / output conditions are input to the crosspoint registers 26 and 27. At this time, the input / output conditions input to the receiving side are set such that the input is output and the output is input. Next, the strobe signal for the cross point register is output from the decoder 23 to store the setting condition of the matrix switch.

[0011]

According to the present invention, the load on the software can be reduced, and the time required for switching the matrix switch can be reduced to about 1/2 of that required in the prior art, so that the communication interruption time due to switching can be shortened.

[Brief description of drawings]

FIG. 1 is a block diagram showing the overall configuration of the present invention.

FIG. 2 is a block diagram showing a configuration example of a conventional matrix switch.

FIG. 3 is a block diagram showing a configuration example of a conventional matrix switch.

FIG. 4 is a cross-point register setting flowchart.

[Explanation of symbols]

 13 transmission system matrix switch 14, 15 selector circuit 16 reception system matrix switch 17-20 selector circuit 22 microcomputer 23 decoder 24 input column register 25 output column register 26, 27 cross point register

Claims (1)

[Claims] 1. A connection between a plurality of communication lines and a plurality of communication lines
In a communication line switching method in which bidirectional communication of transmission and reception is performed by arbitrarily switching and connecting to pair 1, either transmission or reception is used as a reference layer, and the arrangement of the input signal sequence and output signal sequence of the layer is the same. A memory circuit that holds the state of the input signal string in the above-mentioned reference layer and a memory circuit that holds the state of the output signal string in which the input and output signal strings in the other layer are arranged by switching only the input and output signal polarities The communication line switching system is characterized in that the other layer is also arranged by exchanging the input / output signal train states.