JPS60112339A - Informing system for fault of circular data bus - Google Patents

Abstract

PURPOSE:To ensure transmission of the latest fault information at all times among plural devices by always transmitting a fault display packet to a circular data bus and securing such procedures where each device receives the fault display packet to store the contents of the fault and then displays the own fault information to said display packet. CONSTITUTION:When a fault display packet 3 which is always transmitted to a circular data bus 20 in a packet train is received by a data receiving circuit 5, the circuit 5 detects the packet 3 shown in a packet control field 31 and gives a command to a fault display register circuit 7 to fetch fault display fields N0-Nn. While a fault detecting circuit 8 detects a fault of its own device and sends this fault information to a transmission control circuit 9. The circuit 9 writes the fault information to the field N1 corresponding to the number allocated to the own device and then transmits the information to a data transmission circuit 10. The circuit 10 adds an error detecting code field 32 and sends a new fault display packet to the bus 20.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a circular data bus failure notification system, and more particularly to a concession data bus failure notification system that can be applied to electronic exchanges, electronic computers, regional networks, and the like.

Conventionally, failure notifications for circular data buses have been made by detecting failures when there is no response after transmitting a packet, or when an error occurs in a transmitted packet. Therefore, even if a failure occurs in the equipment connected to the concession data bus,
There is a drawback that the fault cannot be detected and notified unless a packet is sent to the faulty device.

An object of the present invention is to transmit fault indication packets to a circular data bus at all times, and each device receives the fault indication packets, stores fault details, and further displays its own fault information in the fault indication packets. It is an object of the present invention to provide a ring data bus fault notification method which eliminates the drawbacks and enables constant notification of the latest fault information between a plurality of devices.

According to the invention, there is provided a ring data bus connecting a plurality of devices, a means for accumulating and displaying the contents of a fault indication packet from the concession data bus, and a means for storing and displaying the contents of a fault indication packet from the concession data bus, and a means for storing fault information of the own device in the fault indication packet. There is obtained a concession data bus failure notification system characterized in that the present invention includes means for displaying and transmitting to the circular data bus, and the failure indication packet is always transmitted to the failure data bus.

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

FIG. 1 is a diagram showing a complete example of the structure of a packet train passing through a concession data bus in an embodiment of the circular data bus failure notification system of the present invention. In the same figure.

The packet string consists of data packets 1, 2, and 4 and a failure indication packet 3, and failure indication packet 3 is transmitted between data packets 2 and 4.

Next, FIG. 2 is a diagram showing an example of the format of the failure indication packet in FIG. 1. In the figure, a failure indication packet 3 includes a packet ff1l control field 31 and a failure indication field N assigned to each node device. ,
N1. ˜Nn and an error detection code field 32.

Next, FIG. 3 is a block diagram showing an embodiment of a node device in the circular data bus failure notification system of the present invention. In the figure, a node device (hereinafter simply referred to as a device) includes a data receiving circuit 5 that receives data packets on a circular data bus 2o, a shift register 6 that stores fault indication packets detected by the data receiving circuit 5, and a data receiving circuit. A fault display register circuit 7 receives the fault display packet from the shift register 6 according to a command from the shift register 6 and displays its contents; a fault detection circuit 8 detects a fault in its own device; the shift register 6; the fault display register circuit 7. Consists of a transmission control circuit 9 that is connected to the fault detection circuit 8 and controls the transmission of fault indication packets, and a data transmission circuit 10 that formats the fault indication packet from the transmission control circuit 9 and transmits it to the concession data bus 20. be done.

Next, the operation of this embodiment will be explained using FIGS. 1 to 3.

When the data receiving circuit 5 receives the fault indicating packet 3 that is constantly transmitted to the circular data bus 20 in the packet sequence shown in FIG. 1, the data receiving circuit 5 detects the fault indicating packet shown in the packet control field 31. Then, the fault display field No. +N1 is input to the fault display register circuit 7.
Command to take in + to Nn. Fault indication register circuit 7
takes in and displays the fault display data passing through the shift register 6 with proper timing. On the other hand, when the fault detection circuit 8 detects a fault in its own device, it sends the fault information to the transmission control port fNr9. When the transmission control circuit 9 receives all of the failure indication packet transmission timing information from the failure indication register circuit 7, the transmission control circuit 9 receives the device number (
For example, the fault information from the fault detection circuit 8 is written in the fault display field N1 corresponding to static 1) and sent to the data transmission circuit 10.

The data transmitting circuit 10 adds an error detection code field 32 and transmits the new fault indication packet to the concession data bus 20.
Send to. Subsequent devices can receive the fault indication packet and know the fault occurrence status.

As is clear from the above explanation, according to the concession data bus failure notification system of the present invention, each device displays its own failure information in a failure indication packet and always sends it to the circular data bus. This results in the effect that the latest failure information is always communicated to each other.

[Brief explanation of the drawing]

FIG. 1 is a diagram showing an example of the structure of a kerat train passing through a circular data bus in an embodiment of the circular data bus failure notification system of the present invention, and FIG. 2 is an example of the format of the failure indication packet in FIG. and FIG. 3 are block diagrams showing an embodiment of a node device in the circular data bus failure notification system of the present invention.

Claims (1)

[Claims] a concession data bus that connects a plurality of devices; means for accumulating and displaying the contents of fault indication packets from the concession data bus; and means for transmitting to a data bus, the failure indicating packet being always transmitted to the root data bus.