JPH06120855A - Automatic signal switching method - Google Patents

Abstract

PURPOSE:To provide an automatic signal switching method which can shorten the switching time of such signals like a duplexed clock, etc. CONSTITUTION:A 0 system package 10 and a 1 system package 20 have the input break detection processing means 11 and 21 which report the signal abnormality states to each other to decide its own state and the state of the other party and output a switching instruction signal. A switching part 40 includes a selection circuit 41 and a processing circuit 42 which inputs the switching instruction signal received from the packages 10 and 20 and decides both instruction signals to second a selection signal to the circuit 41. When the valid one of both switching instruction signals of both systems to be inputted to the circuit 42 is inputted, the circuit 42 transmits a signal to select the system that inputted the valid instruction signal. If the same switching instruction signals are inputted from both systems, circuit 42 transmits continuously the signals equal to the precedent one.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a signal switching method of a transmission device in which clock or data is duplicated in 0 system and 1 system.

In recent years, transmission clocks or data are duplicated in transmission lines and packages for the 0-system and the 1-system to prevent deterioration of transmission quality. However, switching from the 0 system to the 1 system, switching back from the 1 system to the 0 system, and the like still have some unstable factors, and further improvement is desired.

[0003]

2. Description of the Related Art A conventional example will be described with reference to FIGS. FIG. 7 is a diagram showing an example of a conventional automatic signal switching method for switching clocks and the like, and FIG. 8 is a diagram showing an operation sequence example in the conventional example.

Conventionally, when switching between 0 system and 1 system,
The control unit 30 is caused to recognize the states of 0 system and 1 system, and the control unit 30
The switching instruction from the control unit 30 based on the determination of
To the 1 system by the selection circuit 41 of the switching unit 40.
Alternatively, the system 1 was switched to the system 0.

For example, the control unit 30 periodically polls a plurality of monitoring control points periodically and sequentially monitors and controls them. As an input signal such as a clock, the control unit 30 sequentially orders 0-system and 1-system. , Monitor and control.

Then, as shown in the example of FIG.
When a control signal is sent to absorb the state of an input signal such as a 1-system clock or a 1-system clock, and an error is detected in the 0-system, the 0-system with the error is detected as "0-system error". Returns the error notification signal.

Next, when a control signal for absorbing the state of the input signal such as the clock of the 1-system is transmitted, the normal 1-system returns a "1-system normal" notification signal. Control unit 30
Judges two input signals, and switches to the switching unit 40 "0 system →
A switching instruction signal to the "1 system" is transmitted.

Upon receiving the switching instruction signal, the selection circuit 41 of the switching unit 40 switches the signal to be sent to the next stage such as a clock from the 0 system to the 1 system.

[0009]

However, in this circuit, switching is not performed automatically as shown in FIG.
The control unit 40 recognizes the states of the 0 system and the 1 system, and then issues a switching instruction based on the judgment by the control unit 40 to perform the switching.

As one of a plurality of monitoring control points by polling control determined by the control unit 40, a switching instruction is issued when an abnormality is detected. Therefore, if there are many monitoring control points, it takes time to switch due to an abnormality. There was a problem that it took.

An object of the present invention is to solve the above problem and to provide an automatic signal switching method capable of shortening the switching time in switching signals such as dual clocks.

[0012]

FIG. 1 is a block diagram showing the principle of an automatic signal switching method according to the present invention. In the figure, the same reference numerals as those in FIG. 6 indicate the same things, 11 and 21 are input disconnection detection processing means, and 42 is a processing circuit.

According to the present invention, a control unit 30 for inputting abnormality information from each system in a transmission system of a clock duplicated in a 0-system package 10 and a 1-system package 20.
In the automatic signal switching method of switching the selection circuit 41 of the switching unit 40 under the control of 1., the 0-system and 1-system packages 10 and 20 are notified of a signal abnormal state, respectively, and the state of the other party and the self The input disconnection detection processing means 11 and 21 for outputting the switching instruction signal are provided.

Further, the switching section 40 is provided with a processing circuit 42 which inputs a switching instruction signal from each of the packages 10 and 20 of the system, judges both signals and sends the selection signal to the selection circuit 41. .

When a valid switching instruction signal for instructing switching is input from one of the switching instruction signals of both systems which is input to the processing circuit 42, the processing circuit 42 outputs the effective switching instruction signal. A signal for selecting the system to which is input is sent.

Further, when the same switching instruction signal is input from both the 0 system and the 1 system, the processing circuit 42 sends the same signal as the one sent last time, whereby the object can be achieved.

The signal input / output here may be data instead of the clock. Further, the 0-system package 10 and the 1-system package 20 are provided with an identification line for identifying the 0-system or 1-system, and one of the identification lines is the 0-system on the backboard 50 side of the transmission device. Either the mounting side of the package 10 or the mounting side of the 1-system package 20 has a structure that drops to the ground.

The 0-system package 10 and the 1-system package 20 use the same package, and
Different identification signals are sent when the system package 10 is mounted at the mounting position and when the first system package 20 is mounted at the mounting position.

Further, capacitors C11 and C11 are provided in both the 0-system package 10 and the 1-system package 20, respectively.
C12; Time constant circuit 15, 25 having C21, C22
And one of the capacitors C11, C12; C21, C22 of each of the packages 10, 20 is grounded in the package 10, 20, and the other capacitor C12, C11; C22, C21 is grounded. The side lead is connected to a connector connected to the backboard 50 side of each of the packages 10 and 20.

The backboard 50 of the transmission device
Has a structure in which, on the mounting side of the 1-system package 20, the capacitors C22 and C21 whose ground-side leads are connected to the connector of the 1-system package 20 are grounded.

After the power supply of the transmission device is turned on, the 0-system package 10 and the 1-system package 20 start processing in this order. In addition, the 0 package 10
A mounting identification line for identifying mounting is provided on each of the 1-system package 20 and the mounting identification signal of the 0-system package 10 between the processing circuit 42 and the selection circuit 41 of the switching unit 40. Forced selection including a mounting detection circuit 45 for inputting a mounting identification signal of the 1-system package 20 and performing mounting detection processing, and an AND circuit 44 of the transmission signal of the mounting detection circuit 45 and the transmission signal of the processing circuit 42. A circuit 43 is provided.

When neither the 0-system package 10 nor the 1-system package 20 is mounted, the selection circuit 41 selects the 0-system package 10 side.

[0023]

According to the present invention, the processing means 11 for notifying the 0-system package 10 and the 1-system package 20 of the signal abnormal states, and judging the other party's state and the own state and issuing the switching instruction signal. , 21 are provided.

Further, the switching unit 40 is provided with the 0-system package 10
Inputting the switching instruction signal from the 1-system package 20 and the switching instruction signal from the 1-system package 20, making a judgment as shown in the table of FIG. A processing circuit 42 is provided.

By doing so, the processing circuit 42
When a valid switching instruction signal for instructing switching is input from one of the switching instruction signals of both systems to be input to the processing circuit 42, the processing circuit 42 outputs a selection signal for selecting the system to which the valid switching instruction signal is input. Can be sent out.

Further, in order to send the same switching instruction signal from both the 0-system and the 1-system, which occur at the time of state transition during the switching processing, both are effective for switching as shown in the table of FIG. When it is a signal, or when both are signals that are invalid for switching, the processing circuit 42 can send the same signal that was sent previously in order to keep the previous state.

As described above, according to the present invention, the switching time can be shortened by using not the switching by the control of the control system of the software operation but the switching by the hardware circuit directly.

Since the automatic signal switching method of the present invention is used not for non-interruptive interruption but for signals for which interruption is permitted, the signal input / output here is not a clock for which interruption is permitted, It can also be used for data that allows momentary interruptions.

Further, the 0-system package 10 and the 1-system package 20 are provided with an identification line for identifying the 0-system or the 1-system, and one of the identification lines is the 0-system on the backboard 50 side of the transmission device. Mounting side of package 10 or 1-system package 20
Either of the mounting sides of the above shall be constructed so that it can be grounded.

By doing so, the 0-system and the 1-system can be discriminated by the treatment on the backboard 50 side, so that the 0-system package 10 and the 1-system package 20 can use the same package. It will be possible.

Further, two capacitors C11 and C are provided on both the 0-system package 10 and the 1-system package 20, respectively.
Time constant circuits 15 and 25 having 12, C21 and C22 are provided. And capacitors C1, C2, C2, respectively
One of the two, C1 and C22, is grounded in the package, and the other is grounded on the backboard 50 side of the transmission device. In addition, the transmission device backboard 5
0 system 1 package 20 mounted side, 1 system package 20
The one of the capacitors C22 and C21 that is grounded on the package side is grounded.

By doing so, the time constant of the 1-system package 20 becomes larger than the time constant of the 0-system package 10, and the operation start time of the 1-system package 20 is delayed, so the power supply of the transmission device is turned on. After that, processing such as abnormality detection can be started in the order of the 0-system package 10 and the 1-system package 20.

Further, the 0-system package 10 and the 1-system package 20 are provided with mounting identification lines respectively for mounting identification, and further, between the processing circuit 42 and the selection circuit 41 of the switching section 40,
System package 10 mounting identification signal and 1-system package 20
And a compulsory selection circuit 43 including an AND circuit 44 for the signal sent from the mounting detection circuit 45 and the signal sent from the processing circuit 42.

By doing so, the selection circuit 41 can select the 0-system package 10 side when neither the 0-system package 10 nor the 1-system package 20 is mounted. Alternatively, the 1-system package 20 side may be selected.

As a result, when there are a plurality of clocks and data to be transmitted and all the packages are not mounted, the selection signal input to the switching unit 40 becomes unstable and the selection circuit 4
It is possible to prevent the selection of 1 from being mixed up.

[0036]

EXAMPLES Next, examples will be described with reference to FIGS. 2 shows an embodiment of an automatic signal switching method according to the present invention, and FIG. 3 shows an example of an operation sequence in the embodiment of the present invention. Further, FIG. 4 shows an example of a method for discriminating between 0 system and 1 system in the embodiment of the present invention, and FIG. 5 shows 0 in the embodiment of the present invention.
FIG. 6 shows an example of a startup method when the power supplies of the systems 1 and 1 are turned on, and FIG. 6 shows an example of the startup method when both packages are not mounted in the embodiment of the present invention.

In the figure, the same reference numerals as those in FIG.
Reference numerals 12 and 22 are input disconnection detection processing circuits, 13 and 23 are change detection circuits, 14 and 24 are masks, 15 and 25 are time constant circuits, 42 is a processing circuit, 43 is a forced selection circuit, and 44 is AN.
D circuit, 45 mounting detection circuit, 50 backboard, C
11, C12, C21, C22 are capacitors, R11,
R21 is a resistor.

First, a basic automatic signal switching method according to the embodiment of the present invention will be described with reference to FIGS. Signals indicated by circles in FIG. 2 correspond to signals indicated by circles in FIG.

As shown in (1) 0-system abnormality in FIG. 3A, when an abnormality such as an input disconnection is detected in the 0-system package 10, a state information signal for notifying the abnormality is sent from the 0-system to the 1-system. In the 1-system, the 0-system abnormality notification causes the switching process to be performed in the 0-system, so the 1-system holds the selection instruction until the 0-system processing is completed. If the state of the 1-system that has been sent to the 0-system processing circuit at regular intervals by this time is normal, a switching instruction is sent to the switching unit 40 and another system (1-system) selection instruction is sent.

However, if the state of the 1-system is abnormal, the switching instruction remains the self-system (0-system) selection instruction. And
The system 1 is informed of the content of the switching instruction to the switching unit 40. The 1-system follows the switching instruction of the 0-system.

That is, when the switching instruction of the 0 system is the own system (0 system) selection, the other system (1 system) selection instruction is issued, and when the 0 system switching instruction is the other system (1 system) selection, It issues an instruction to select its own system (0 system).

As described above, when an abnormality such as a clock interruption occurs in the 0-system, the 0-system performs processing, and the 1-system holds a selection instruction by processing standby, and after the 0-system processing is confirmed, a switching instruction is issued. Switching out is possible by putting it out.

Next, as shown in FIG. 3 (2) 1-system abnormality, when an abnormality such as an input disconnection is detected in the 1-system package 20, a status information signal of abnormality notification is sent from the 1-system to the 0-system. To do.

At the same time, processing is performed in the 0-system due to the abnormality detection of the 1-system, and since there is a switching instruction from the 0-system, the 1-system waits for the processing. In the 0-system, when the status information signal of the abnormality notification from the 1-system is input, if the 0-system clock interruption state is normal and the 0-system clock is selected, the 0-system switching instruction is continued, If the 0 system is abnormal and the 1 system is selected, the 0 system switching instruction is issued. In any case, the 0 system is selected. Then, the switching unit 40 is notified of the contents of the switching instruction to the first system. The 1-system retains the selection instruction so far, receives the processing notification from the 0-system after confirming the processing of the 0-system, sends a switching instruction to the 0-system to the switching unit 40, and Then, the switching unit 40 is notified of the content of the switching instruction.

In this way, switching is possible. Since the automatic signal switching method of the present embodiment is used not for non-interruptive interruption but for signals for which instantaneous interruption is allowed, by replacing the clock with data in FIG. , It can also be used for data that allows interruption.

FIG. 4 shows 0 system and 1 system in the embodiment of the present invention.
It is a figure which shows the example of the identification method of a system. One terminal of the resistor R11 of the 0-system package 10 is the power source of the backboard +
Although it is connected to V _CC , the other terminal is open on the backboard 50 side, so "H" is taken out as an identification signal.

On the other hand, one terminal of R21 of the 1-system package 20 is connected to the power source + V _CC of the backboard 50,
Since the other terminal is connected to the ground GND of the backboard 50, "H" is taken out as an identification signal. This identification signal can be used to identify the 0-system and the 1-system, and can be used to create a switching operation sequence.

FIG. 5 shows an example of a start-up method at the time of power-on of the 0-system and 1-system in the embodiment of the present invention.
In the 1-system package 20, using the masks 14 and 24 and the time constant circuits 15 and 25 to input the status information from the other side, which is input to the processing units 12 and 24, until the package becomes stable after the transmission device is powered on. For a certain period of time, another system is made to appear to be in an abnormal state temporarily and masked like an input interruption.

A time constant circuit is formed by the capacitor C11 of the time constant circuit 15 on the 0-system 10 side and a resistor (not shown). However, in addition to the capacitor C21 of the time constant circuit 15 on the 1-system 20 side, a backboard. Capacitor C2 through 50
2 is connected to ground GND, resulting in capacitor C2
Since it is connected in parallel with 1, the time constant becomes longer than that of the 0-system package 10 in forming a resistor and a time constant circuit (not shown).

Therefore, after turning on the power of the transmission device,
The masks 14 and 24 can be masked with the respective time constants in the order of the 0-system package 10 and the 1-system package 20, and processing such as abnormality detection is started in the order of the 0-system package 10 and the 1-system package 20. become.

Next, FIG. 6 shows an example of a start-up method when both packages are not mounted in the embodiment of the present invention. Also, 0
The system package 10 and the 1-system package 20 are each provided with a mounting identification line for mounting. When the packages 10 and 20 are mounted, the ground level "L" rises from the backboard 50 side, and when not mounted, "H" is mounted. It is sent to the detection circuit 45.

When both the 0-system package 10 and the 1-system package 20 are mounted, since "L" is input to both the mounting detection circuits 45, the AND circuit 44 outputs the output of the processing circuit 42. Follow the signal.

When neither the 0-system package 10 nor the 1-system package 20 is mounted, "H" is input to both of the mounting detection circuits 45 and a switching instruction is input to the processing circuit 42. Both signals are in the state of no input, and thus are in an unstable state. In such a case, the AND circuit 44 sends the 0-system selection signal. Here, as the selection signal to be transmitted, a signal for selecting one system may be transmitted.

[0054]

As described above, according to the present invention,
When switching dual clocks, etc., a method of directly issuing a switching instruction from the 0-system and 1-system packages to the switching unit is used, so that the switching time can be reduced, and as a result, the abnormal time of the transmitted clock, etc. Can be reduced.

Further, since the switching operation can be set in advance such as giving priority to the 0 system, it is possible to avoid confusion when an abnormality occurs in a plurality of lines at one time in operation and maintenance handling a plurality of lines. Etc., which greatly contribute to operation and maintenance.

[Brief description of drawings]

FIG. 1 is a principle configuration diagram of an automatic signal switching method according to the present invention.

FIG. 2 is an embodiment of an automatic signal switching method according to the present invention.

FIG. 3 is a diagram showing an operation sequence example in the embodiment of the present invention.

FIG. 4 is an example of a method for discriminating between a 0 system and a 1 system in the embodiment of the present invention.

FIG. 5 is an example of a start-up method at power-on of the 0-system and 1-system in the embodiment of the present invention.

FIG. 6 is an example of a start-up method when both packages are not mounted in the embodiment of the present invention.

FIG. 7 is an example of a conventional automatic signal switching method.

FIG. 8 is a diagram showing an operation sequence example in a conventional example.

[Explanation of symbols]

 10,200 System package, 1 system package 11,21 Input break detection processing means 12,22 Processing circuit 13,23 Change detection circuit 14,24 Mask 15,25 Time constant circuit 30 Control section 40 Switching section 41 Selection circuit 42 Processing Circuit 43 Forced selection circuit 44 AND circuit 45 Mounting detection circuit 50 Backboard C11, C12, C21, C22 Capacitor R11, R21 Resistance

Claims (5)

[Claims] 1. A control unit (3) for inputting abnormality information from each system regarding a transmission device of a clock that is duplicated in a 0 system package (10) and a 1 system package (20).
In the automatic signal switching method for switching the selection circuit (41) of the switching unit (40) under the control of 0), the 0-system package (10) and the 1-system package (2)
0) to notify each other of signal abnormal conditions, and
An input disconnection detection processing means (11, 21) for outputting a switching instruction signal based on the state of the other party and its own state is provided, and the switching unit (40) includes the packages (10, 20) is provided with a processing circuit (42) for inputting the switching instruction signal from 20), judging the signals of both systems and sending the selection signal to the selection circuit (41), and inputting to the processing circuit (42) When a valid switching instruction signal for instructing switching is input from one of the switching instruction signals of 1), the processing circuit (42) outputs a signal for selecting the system to which the valid switching instruction signal is input, When the same switching instruction signal is input from both systems, the processing circuit (42) sends out the same signal as previously sent out, the automatic signal switching method. 2. The automatic signal switching method according to claim 1, wherein the input / output signals are data instead of clocks. 3. The 0-system package (10) and the 1-system package (2) according to claim 1 or 2,
An identification line for identifying 0 system or 1 system is provided on both 0),
One of the identification lines is grounded on the backboard (50) side of the transmission device, and the 0-system package (10) and the 1-system package (20) use the same package. The 0-system package (10) and the 1-system package (20) are mounted between the position where the 0-system package (10) is mounted and the position where the 1-system package (20) is mounted. An automatic signal switching method characterized by transmitting an identification signal different from that of. 4. The 0-system package (10) and the 1-system package (2) according to claim 1 or 2,
0) to both capacitors (C11, C12;
A time constant circuit (15, 25) having C21, C22) is provided, and one of the capacitors (C11, C12; C21, C22) of each of the packages (10, 20) is provided in the package (10, 20) is grounded, and the ground side leads of the other capacitors (C12, C11; C22, C21) are connected to the respective packages (10, 20).
Of the transmission device, the backboard (50) of the transmission device is mounted on the first system package (20) mounting side of the first system package (2).
The capacitor (C22, C21) whose ground side lead is connected to the connector of (0) is grounded, and after the power of the transmission device is turned on, the 0-system package (1
0), the automatic signal switching method characterized by starting the processing in the order of the 1-system package (20). 5. The 0-system package (10) and the 1-system package (2) according to claim 1 or 2,
0) is provided with a mounting identification signal line for mounting respectively, and the 0-system package (10) is mounted between the processing circuit (42) and the selection circuit (41) of the switching unit (40). A mounting detection circuit (4) for inputting an identification signal and a mounting identification signal of the 1-system package (20) to perform mounting detection processing.
5) and a forced selection circuit (43) consisting of the output signal of the mounting detection circuit (45) and the output signal of the processing circuit (42), and the 0-system package (10). , The 1-system package (2
When neither of 0) is mounted, the selection circuit (4
1) is an automatic signal switching method, characterized in that the 0-system package (10) side is selected.