JPH0242838A - Duplexing line switching system - Google Patents

Abstract

PURPOSE:To easily execute error detection processing and to eliminate the limitation of a communication speed by adding a prescribed pattern to data in a transmitting side and executing line switching in a receiving side according to the presence and absence of an error in the pattern. CONSTITUTION:In the transmitting side, a pattern data (n)-bit, which has a prescribed pattern sequence to be generated in a pattern generating circuit 2, is added to a transmitting data (m)-bit by a pattern inserting circuit 3 and sent to routes A and B with (m+n)-bit constitution. In the receiving side, the prescribed pattern sequence is detected from respective receiving data, which come from the routes A and B, by a pattern detecting circuit 4 and the receiving data of the (m)-bit corresponding to transmitting data are separated by a separating circuit 5 in correspondence to a detected result and sent to a selecting circuit 6. For example, when a trouble is generated in the route A and the error is detected in the prescribed pattern by the circuit 4 while the receiving data of the route A are received, connection is switched so that the receiving data of the route B can be selected and outputted by the circuit 6. Thus, the error detection processing is easily executed and the limitation is not given to the communication speed.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a duplex line switching system, and more particularly to a duplex line switching system when lines are duplexed to ensure reliability in data transmission.

[Conventional technology]

In this type of conventional duplex line switching system, when an error is detected in the received data stream coming from the selected line, the line is switched to the other line.

[Problem to be solved by the invention]

The disadvantage of the conventional duplex line switching method described above is that it takes processing time to analyze the internal use of the selectively received data string and detect errors, and the communication speed is limited by the processing speed of error detection. There is.

[Means to solve the problem]

The duplex line switching system of the present invention includes a pattern generation circuit that generates data having a predetermined pattern on the transmission side and a pattern insertion circuit that multiplexes the data generated by the pattern generation circuit and the transmission data. two systems of pattern detection circuits for detecting the pattern data; two systems of separation circuits for removing the pattern data from the received data string and outputting the received data; and a selection circuit that selects one of the received data of the system.

〔Example〕

Next, the present invention will be explained with reference to the drawings.

FIGS. 1(a) and 1(b) are block diagrams showing one embodiment of the present invention. Reference number 1 in the figure is a transmission device equipped with the transmitting and receiving circuit shown in the figure (b), 2 is a pattern generation circuit,
3 is a pattern insertion circuit, 4 is a pattern detection circuit, 5 is a separation circuit, and 6 is a selection circuit. The transmission device 1 sends and receives data signals to and from each other via route A and route B duplex lines.

Transmission in the transmission device 1 is performed by sending the output signal from the same circuit to both routes, and reception is performed by providing a circuit for each route and transmitting the output signal of the circuit in which no error has occurred. This is done by selecting and outputting.

That is, in FIG. 2B, on the transmitting side, the pattern insertion circuit 3 adds n bits of pattern data having a predetermined pattern sequence generated by the pattern generation circuit 2 to the m bits of the transmission data, so that (m + n) It is sent to route A and route B in bit configuration.

On the receiving side, a pattern detection circuit 4 detects the above-mentioned predetermined pattern sequence from each received data arriving from routes A and B, and a separation circuit 5 detects the m-bits corresponding to the above-mentioned transmission data according to the detection result. The received data is separated and sent to the selection circuit 6. If the received data from routes A and B are both normal and, for example, a failure occurs in route A while the selection circuit 6 selects the received data from route A and obtains the received data, then route A When the pattern detection circuit 4 on the side detects an error in the predetermined pattern, the 3M selection circuit 6 detects an error in the predetermined pattern.
switches the connection so that the received data of route B is selected and output.

〔Effect of the invention〕

As explained above, the present invention simplifies error detection processing compared to conventional methods by adding a predetermined pattern to data on the transmitting side and switching lines depending on whether or not there is an error in the pattern on the receiving side. This has the effect that there is no need to impose restrictions on communication speed.

[Brief explanation of the drawing]

1 (a> and (b) are block diagrams showing an embodiment of the present invention. 1... Transmission device, 2... Pattern generation circuit, 3...
・Pattern insertion circuit, 4...Pattern detection circuit, 5.
... Separation circuit, 6... Selection circuit.

Claims (1)

[Claims] A pattern detection circuit that includes a pattern generation circuit that generates data having a predetermined pattern on the transmission side and a pattern insertion circuit that multiplexes the data generated by the pattern generation circuit and the transmission data, and that detects the pattern data on the reception side. two systems, two separation circuits that remove the pattern data from the received data string and output the received data, and one of the two systems of received data in response to the error detection result in the pattern detection circuit. A duplex line switching system equipped with a selection circuit for selection.