JPS59158146A - Data highway device - Google Patents

Abstract

PURPOSE:To eliminate almost completely the system failure of a looped data transmission network by reconstruct one long loop by a loop-back line even in case of an erroneous transmission originating from a fault of a signal line. CONSTITUTION:When a signal received from a high-order station through the signal line is disconnected the loop-back control part 5 of said station operates a disconnection detecting circuit 11 to output a signal with a logical level ''1''. This signal with the logical level ''1'' serves as the control signal of an OR circuit 13 and the 1st switching circuit 14 regards the digital receive signal of a signal converter 4 which converts a transmission line signal received through a low-order station through the loop-back line as the receive data of the station. The signal with the logical level ''1'' outputted by the OR circuit 13 is inverted by an inverter circuit 18 to a logical level ''0'' to obtain a control signal, which permits an AND circuit 19 to stops the transmission of a signal to the high- order station through a signal converter 2 and the loop back line. Thus, one large data highway from the high-order station to this station is constituted by the loop-back line and the transmit data sent out of the high-order station through the loop-back line is received by this station.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention is an application system that is configured in a loop with two transmission lines, a signal line and a loopback line, through which signals are sent in different directions, and that transmits data between multiple stations. -Relating to highway equipment.

Conventionally, in this type of data highway equipment, if one station out of N (N≧2) stations forming a loop data transmission network fails, data transmission between all stations in the loop data transmission network is interrupted. As a means to avoid this, we will monitor the data reception section of the Gata Highway control of each station for frame synchronization loss, error check failure, etc. If the system continues, the relevant station will automatically bypass the system, thereby allowing data transmission only between other stations other than the relevant station.

This type of system is very effective if the cause of the failure is a hardware abnormality in the data highway control units of two stations, as only the corresponding stations need to be affected. If the cause of the failure is on the transmission line side, there is a possibility that bypassing one station will cause successive lower stations to fall into a bypass state.

SUMMARY OF THE INVENTION It is an object of the present invention to provide a data highway device which solves the above-mentioned conventional drawbacks and allows continuous operation of a roots-like data transmission network without system failure.

According to the present invention, in a data highway device configured in a loop with two transmission lines, a signal line and a loopback line, through which signals are sent in different directions, and transmits data between two or more stations, Each station.

When the signal received from the signal line is disconnected or when a transmission error is detected, the signal received from the roots bar or link is used instead of the signal received from the signal line as the reception signal, and the signal is sent to the roots bar or link. A data highway characterized by having means for stopping a transmitted signal to be transmitted, and means for transmitting transmitting data to be transmitted to a signal line also to the loopback line when the signal received from the loopback line is disconnected. equipment is obtained. In other words, in the present invention, when a disconnection of the signal received from the signal line or a transmission error is detected in the data receiving section of the router control section of the station, the corresponding station receives the signal sent from the loopback line. - At the end of the day, it stops sending signals to the loopback line, and when the upper station detects that the signal received from the loopback line is disconnected, it forcibly roofs the data being sent to the signal line. It is sent to the 0 back line, and as a result, one long loop is rebuilt from the upper station to the roof 0 back line of the corresponding station.

The transmission signal from the upper station can be received by the station concerned.

A computer highway system according to the present invention will be explained below with reference to two drawings.

FIG. 1 is a schematic diagram showing the configuration of a computer highway/system according to the present invention. The N stations are connected in the same manner and perform data transmission between the N stations. Any one of these stations, for example, ≠1 station, serves as a master station and intensively corrects delays occurring in the looped Ganita transmission network and monitors the entire system. In FIG.

The counterclockwise line is the signal line, and the clockwise line is the rootsback line. 2 Normal master station ≠ 1 sends the same signal to both the loop/<, 7 line and signal line, and connects from the roof 0 Tsuktsuku line. The received signal is discarded. On the other hand, in each slave station 2-4N, the received signal from the loopback line is only regenerated and relayed and transmitted to the lower station.

FIG. 2 is a frame configuration diagram of data flowing in the scene 0 data transmission network of FIG. 1, where F is a frame synchronization section, D is a data section, and C0NT is a control signal section.

This is the Fe2 id frame check sequence part.

FIG. 3 is a block diagram showing the configuration of an embodiment of a station of a data network device according to the present invention.

In the figure, 1 to 4 are signal converters, of which 1
and 4 are for converting the transmission line signal from the transmission line into a digital signal, and 2 and 3 are for converting the digital signal into a transmission line signal to be sent to the transmission line. Reference numeral 5 denotes a loopback control section which performs loopback control in the present invention. 6 shows a timing extraction circuit, and the receiving r
-This is a circuit that extracts timing from evening. Reference numeral 7 denotes a loop synchronization control unit, which is a circuit that only the master station≠1 has, and which intensively corrects delays occurring in the loop data transmission network and monitors the entire system.

Reference numeral 8 denotes a data highway control section, which is divided into two parts: 7' - an evening reception section and a data reception section. this house,
The data receiving section determines the presence or absence of frame synchronization, determines whether frame synchronization is established (9) or removed, and checks Fe2 to detect whether the frame synchronization is good or not. Then, the received data is imported only when all checks are normal. On the other hand, 7″-
The evening transmitter creates frame synchronization, creates Fe2, 7
``'' - data is inserted into the control signal section, control data is inserted into the control signal section, and the transmission data is sent out. 9 indicates an interface section with a terminal device (not shown).

FIG. 4 is a circuit diagram showing in detail the configuration of the loopback control section 5 in FIG. 3. In fig.

IJ and 12 are circuits that detect disconnection of the signal line reception signal sent from the signal converter 1 and the loop bar and line duplication signals sent from the signal converter 4, respectively, and when disconnection is detected, the logic Outputs level "1". Reference numeral 13 denotes an OR circuit which takes the logical sum of the output from the disconnection detection circuit 11 and the loop/pull command sent from the data highway control section 8 and outputs a control signal. 14 is a first switch which switches the signal line reception signal sent from the signal converter 1 and the loopback line reception signal sent from the signal converter 4 and outputs the received data by the control signal from the OR circuit 13; It is a circuit. 15 is a second switching circuit that switches between the loopback line reception signal sent from the signal converter 4 and the transmission data sent from the data highway control section 8 in accordance with the control signal output from the disconnection detection circuit J2. . 16
is an exclusive NOR circuit that performs an exclusive NOR between the master station display and the loopback signal through command sent from the loop synchronization control unit 7 and outputs a control signal. 17 is.

Transmission r- sent from the iway control unit 8
The output signal of the second switching circuit 15 is connected to the exclusive NOR circuit 1.
This is a third switching circuit that switches according to a control signal from 6. 18 is an inverter circuit that outputs a control signal obtained by negating the control signal of the OR circuit 13). Reference numeral 19 denotes an AND circuit for controlling the roof 0 back line transmission signal output from the third switching circuit in accordance with the control signal from the in/output circuit 18.

In FIG. 4, when the master station ≠ 1, the master station display from the loop synchronization control section 7 is at a logic level of 1''.

Each slave station 2~≠N is set so that the master station display is at the logic level ``0''.In addition, for each slave station 2~≠N, the root is 0, and the signal through command is set at the logic level ``0''. o''. If the master station ≠ 1, the roof 0 synchronization control unit 7 sends out a loopback signal through command based on the control data of the control signal section C0NT in the received data. That is, the loopback signal Through command is 2 normal logic level '0'
'', but if the signal sent from the higher-level station via the signal line is disconnected or a transmission error is detected.
Then, control data indicating a failure is placed in the control signal section C0NT constituting the data, and the loop synchronization control section 7 detects it and becomes the logic level "'1". Therefore, slave station≠
2 to ≠N, the control signal from the exclusive NOR circuit 16 is always at the logic level "1", so the second switching circuit 1
The output signal of No. 5 becomes the output signal of the third switching circuit 17.

On the other hand, when the master station ≠ 1, the control signal from the non-alternative NOR circuit becomes logic level ``1'' and the third switching occurs when the 1 normal Lucy Back signal through command is at the logic level "'O" and is detected. The circuit 17 passes through the output signal of the second switching circuit 15 as is.

Next, the operation of the embodiment of the present invention will be explained with reference to FIGS. 3 and 4.

First, the operation in 2 normal conditions will be explained. A transmission line signal sent via a signal line from an upper station is received by a signal converter 1, and the digital reception signal converted here is input to a loopback control section 5. In the loopback control unit 5, the control signal from the OR circuit 13 is at the logic level "o".
Therefore, the first switching circuit 14 outputs the diisotal reception signal as it is as reception data. This received data is input to the timing extraction circuit 6 and also input to the loop synchronization control unit 7 only if the master station≠1. Child station 2~
If ≠N, this received data is directly input to the data/way control section 8. In the master station 41, the loop synchronization control unit 7 uses the received data to correct delays occurring in the root-0 state dinner transmission network and to monitor the entire system. It is output to the highway device 8. The data/way control unit 8 performs frame synchronization playback from the received data, outputs the data 9, passes this data to the interface unit 9, and uses the data passed from the interface unit 9. Transmission data to which a frame synchronization signal etc. have been added is sent to the loopback control section 5. The loopback control unit 5 immediately sends this transmission data to the signal converter 3, which converts this transmission data into a transmission line signal and outputs this transmission line signal to the lower station via the signal line. do. Here, master station 4 = 1
Only the third
The switching circuit 17 outputs the transmission r-t, and the AND circuit 19
This transmission data is sent to the signal converter 2 via the signal converter 2, which converts the transmission data into a transmission line signal, and outputs this transmission line signal to the upper station via the loopback line.

On the other hand, the transmission line signal sent from the lower station via the roof 0 back line is received by the signal converter 4, and the dinotal reception signal converted here is input to the loopback control section 5. When the slave station ≠ 2 to 4N, the control signal from the disconnection detection circuit 12 is at the logic level ``0'', so the second switching circuit 15 outputs the above received signal, and the exclusive NOR circuit 16 outputs the control signal. Since the signal is at the logic level "1", the third switching circuit 17 outputs the reception signal sent from the second switching circuit 15, and the reception signal output from the third switching circuit 17 is an AND signal. It is input to the signal converter 2 via the circuit 19. That is, in the slave stations 4P2 to 4PN, the received signal output from the signal converter 4 is immediately input to the signal converter 2 via the loopback control unit 5. Become.

This received signal is converted into a transmission line signal by a signal converter 2 as a transmission signal.

This transmission line signal is output to the upper station via a loopback line. On the other hand, if the master station≠1, the control signal from the exclusive NOR circuit 16 is at the logic level LIO11, so the second
The received signal sent from the switching circuit 15 is stopped at the third switching circuit 17. That is, when the master station≠1, the loopback control unit 5 discards the signal sent from the lower station via the loopback line.

Next, the operation when the signal received from the upper station via the signal line is disconnected will be explained. Such a disconnection occurs when the signal line between the upper station and the relevant station is disconnected.

At this time, the disconnection detection circuit 11 operates in the loopback control unit 5 of the station and outputs a logic level "1". This logic level "1" signal is the OR circuit 130 control signal9. The first switching circuit 14 uses a signal obtained by converting a transmission line signal received from a lower station via a roots-back line into a dinotal reception signal by the signal converter 4 as reception data of the station. On the other hand, a signal of logic level "1#" outputted from the OR circuit 13) becomes a control signal of logic level "0" by the inverter circuit [8].・Eway moaning part 8 r
- The evening receiving unit detects that the status sent from the upper station via the signal line has changed to the status sent via the loopback signal line of the lower station, and transmits the data. A control arc indicating a fault is placed on the control signal section C0NT of the transmission r-event sent from the sound μ.

On the other hand, at the second-ranked station, signals are no longer sent to the lower-ranked station via the loopback line, so
In the Luzino 4-switch control section 5, the disconnection detection circuit 12 operates and outputs a logic level "'1".

The second switching circuit 15 outputs all the transmission data in response to the control signal of logic level ``1'' from the disconnection detection circuit 12.

If the relevant upper station is a slave station ≠ 2 to ΦN, exclusive NOR circuit 1
Since the control signal from 6 is always at the logic level tt 1 n, the third switching circuit 17 outputs the transmission data output from the second switching circuit 15, and this transmission data is subjected to signal conversion via the AND circuit 19. Sent to vessel 2. Signal converter 2
converts the transmitted signal into a transmission line signal, and this transmission line signal is sent to the upper station of the upper station concerned via the Rootsback line.

On the other hand, in the master station≠1, the loop synchronization control section 7 turns on the loop no.<> through command, that is, turns on the logic level "1", based on the control data indicating that the control signal section C0NT is faulty in the received data. The control signal from exclusive NOR circuit 16 becomes logic level "'1".

Therefore, if the parent station≠1 is the upper station, the parent station is.

The transmission data is converted into a transmission line signal by the signal converter 2 and sent to the upper station of the relevant upper station (master station) via the loopback line. teeth,
The signal received from the lower station of the master station via the loopback line is passed through as is and sent to the upper station of the master station via the loop back line.

As a result, one large data highway route is constructed from the upper station to the station using the loopback line.
Transmission data sent from the higher-level station via the loopback line can be received at the station.

When the above-mentioned disconnection is restored, the disconnection detection circuit 1 of the station concerned outputs a logic level of 60'', and the disconnection detection circuit 1 of the upper station of the concerned station
2 outputs a logic level ``0'''' and restores the information before the control data of the control signal section C0NT constituting part 7 was cut off, thereby resuming the normal operation described above. Return to

Next, the operation when a transmission error occurs in a signal received from a higher-level station via a signal line will be described. At this time, the data highway control unit 8 in the station continuously monitors transmission errors for a certain period of time.

If the transmission error is not recovered within the certain period of time, the loopback command to the loopback control unit 5 is turned on, that is, the logic level is set to "]". This logic level "1" signal becomes a control signal for the OR circuit 13. The following operations are the same as those in the case of disconnection described above, so the explanation will be omitted. However, in this case, the received signal sent from the higher-level station via the loopback line is input to the computer highway control unit 8 as received data, but the computer highway control section 8 Part 8.

The loopback command was turned on even when there was no transmission error on this receiving date! , even.

Even if such control is performed, the results of monitoring for out-of-synchronization, error checking, etc. of the received data inputted by the data receiving section of the 7''-way control section 8.

If this out-of-synchronization or incorrect check failure continues.

The station determines that there is an abnormality in the data receiving section of the data-eway control section 8, and bypasses the station.

As is clear from the above description, one aspect of the present invention.

Even in the event of a transmission error caused by a failure in the signal line, by rebuilding one long root using the roof-0 back line, system failures in the roof-0 data transmission network can be almost completely eliminated. be.

[Brief explanation of drawings]

° Figure 1 is a schematic diagram showing the configuration of a data highway system according to the present invention, and Figure 2 is a diagram showing the configuration of the data highway system in Figure 1.
FIG. 3 is a block diagram showing the structure of an embodiment of a station of the data highway device according to the present invention. FIG. 4 is a circuit diagram showing in detail the configuration of the loopback control section in FIG. 3. 1.2, 3.4... Signal converter, 5... Loopback control unit, 6... Timing extraction circuit, 7... Loop synchronization control unit, 8... Garta highway control unit, 9・
...Terminal device interface section, 11, 12... disconnection detection circuit. 13...OR circuit, 14.15...switching circuit, 16
...Exclusive NOR circuit, 17...Switching circuit, 18...
・Inverter circuit, 19...AND circuit. 25 Figure 1 Figure 2 F D C0NTF
C5 Figure 3

Claims (1)

[Claims] 1. In a data highway device configured in a loop with two transmission lines, a signal line and a loose pack line, through which signals are sent in different directions, and transmits data between multiple stations, When the signal received from the signal line is disconnected or when a transmission error is detected, each station uses the signal received from the loopback line as reception data instead of the signal received from the signal line, and sends the signal to the rootsback line. A data highway characterized in that it has means for stopping a transmission signal to be transmitted, and means for transmitting transmission data to be transmitted to a signal line also to the loose pack line when the signal received from the loopback line is disconnected. Device. Margin below