JP2734859B2 - Communication path switching device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention is used for digital communication. In particular, the present invention relates to a communication path switching monitoring technology having a system confounding function.

[0002]

2. Description of the Related Art System switching of a duplex communication channel is performed by ACT / SBY (Active / S) received from both transmission side systems.
In this case, system switching is performed by a system selection signal generated by the receiving side in response to a (standby) signal, and normality of system switching is guaranteed by monitoring the system switching signal.

[0003]

In this system, the normality of the system switching cannot be guaranteed if there is an abnormality in the device that actually selects the reception data by the system selection signal.

The present invention has been made in view of such a background, and provides a communication path switching apparatus capable of monitoring whether or not the system has been properly selected by checking the parity of received data immediately after switching. With the goal.

[0005]

According to the present invention, there are provided two transmission apparatuses each including a driver having a system confound and transmitting data to a duplex communication path, and two transmission apparatuses from the transmission apparatus. And a selector for selecting the data from the receiver.
A communication path switching device including a receiving apparatus of a system, wherein the transmitting apparatus includes a unit that transmits a signal to which a parity bit of reverse logic is added to each of the two communication paths immediately after switching, The receiving side device is provided with means for checking a parity logic of the received data.

[0006]

According to the present invention, the communication path switching device of the present invention adds parity bits of different logics (ODD and EVEN) to transmission data on the transmission side and transmission side on the transmission side in a communication path having system confounding. The normality of the system switching is monitored by simultaneously switching the system selection of the received data and the logic selection of the parity check in synchronization with the system selection signal generated by the ACT / SBY signal received from both systems.

[0007]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described with reference to FIG. FIG. 1 is a configuration diagram of an embodiment of the present invention.

According to the present invention, there are provided two transmitting side devices 15 and 15 'each including drivers 2 and 2' for transmitting data to a duplex communication path having system confounding, and the transmitting side devices 15 and 15 ' Receivers 4 and 4 'for receiving the two systems of data from 15', and receivers 4 and 4 '
In the communication path switching device including two receiving devices 16 and 16 'each including selectors 6 and 6' for selecting the data from the communication devices, the transmitting devices 15 and 15 ' Parity generating circuits 1 and 1 'are provided as means for transmitting a signal having a parity bit of reverse logic added to each of the two communication paths, and the receiving devices 16 and 16' check the parity logic of the received data. And parity check circuits 7 and 7 '.

Next, the operation of the embodiment of the present invention will be described with reference to FIGS. FIG. 2 is a flowchart showing the operation of the embodiment of the present invention.

[0010] From transmission data of system 0 and system 1 to transmission side C
PUs 9 and 9 'receive the switching instruction (S0 and S').
1). The 0-system parity generation circuit 1 and the 1-system parity generation circuit 1 'add parity of opposite logic to the 8-bit data (S2), and the 9-bit communication path data 10 is transmitted to the receiver 4 via the drivers 2 and 2'. And 4 '. The system selection circuits 8 and 8 'of the receiving-side devices 16 and 16' receive the system selection signal 14
And 14 ', and switches the selectors 6 and 6' and the parity check circuits 7 and 7 '(S
3). Further, the parity check circuits 7 and 7 'check the parity logic (S4). At this time, if an error occurs in the parity check, the receiving CPUs 3 and 3 '
Determines that the system selection system of the receiving-side devices 16 and 16 'is abnormal, and outputs an abnormality detection signal (S6).

Thus, the system selection signals 14 and 14 '
After the selectors 6 and 6 'are switched, the check results of the parity check circuits 7 and 7' are monitored to confirm the normality of the system switching.

[0012]

Since the parity switching is finally checked by checking the parity logic, the system switching fault detection capability is improved, and as a result, the reliability of the entire system is improved.

[Brief description of the drawings]

FIG. 1 is a configuration diagram of an embodiment of the present invention.

FIG. 2 is a flowchart showing the operation of the embodiment of the present invention.

[Explanation of symbols]

 1, 1 'parity generation circuit 2, 2' driver 3, 3 'reception side CPU 4, 4' receiver 6, 6 'selector 7, 7' parity check circuit 8, 8 'system selection circuit 9, 9' transmission side CPU 100 system communication data 11 system 1 communication data 12 system 0 ACT / SBY signal 13 system 1 ACT / SBY signal 14, 14 'system selection signal 15, 15' transmission side device 16, 16 'reception side device

Claims (1)

(57) [Claims] 1. Two systems of transmitting devices each including a driver having system confounding and transmitting data to a duplex communication channel, a receiver for receiving two systems of data from the transmitting device, And a selector for selecting the data from the receiver. The communication path switching device includes two receiving apparatuses each including a selector for selecting the data from the receiver. A communication path switching device, comprising: means for transmitting a signal to which the parity bit has been added; and wherein the reception-side apparatus has means for checking a parity logic of the received data.