JPH054861B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a power outage detection method at a partner station of opposing communication devices.

[Conventional technology]

Conventionally, in a power outage detection method for communication devices, when a communication device that has experienced a power outage detects a power outage, it sends information indicating that a power outage has occurred (for example, “ H”) to the opposite device.

On the other hand, the receiving unit of the opposing device searches the time slot for power outage information, and detects a power outage in the opposing communication device using a means that determines a power outage if the power outage information bit is “H”. It has been common practice to make a determination before communication between devices is interrupted to determine whether a power outage has occurred in the other communication device.

[Problem that the invention seeks to solve]

In the conventional power outage detection method described above, when a characteristic deterioration or failure of the transmission path between the two communication devices occurs, a code error is generated in the communication signal sequence between the two communication devices, and information on the power outage is detected. This can also cause code errors in bits, which may cause the opposing receiving unit to incorrectly determine that the other party's communication device has experienced a power outage. This may lead to failures in the communication device or transmission path being undiscovered, which can have a significant impact on failure recovery. There is a problem with it.

SUMMARY OF THE INVENTION An object of the present invention is to provide a power outage detection method that prevents errors in power outage determination and performs stable power outage detection between communication devices without affecting recovery from failures in transmission lines or the like.

[Means for solving problems]

The power outage detection method of the present invention includes a means for detecting a power outage in one communication device, a means for maintaining power necessary to secure communication for a certain period of time, and multiplex transmission of power outage signals to the other communication device based on this detection. power outage detection means for detecting the power outage signal on the other opposing communication device, communication stoppage detection means for detecting communication stoppage of the communication device, and determining the first arrival of detection signals from both of these detection means. and a means for outputting a power failure determination signal when a detection signal from the power failure detection means arrives first.

〔Example〕

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

FIG. 1 shows the system configuration during communication between the two parties.

The receiving section of the communication device 1 receives a signal from the transmitting section of the opposing communication device 2 via the transmission path 101, and the receiving section of the communication device 2 receives the signal from the transmitting section of the communication device 1 via the transmission path 101. and transmits signals between the two communication devices.

FIG. 2 shows a transmitting section of the communication device 1. As shown in FIG.

In FIG. 2, when the voltage of the device supply power source 102 decreases due to a power outage or the like, it is detected by the power outage detection section 3 and a power outage detection signal 103 is generated. This power failure detection signal 103 is input to the connector 6 connected to the power supply holding section 5, and the connector 6 is closed to ensure power to the communication device ₁ for a certain period of time T1. At the same time, the power outage detection signal 103 is input to the power outage signal generator 4,
The power outage information 104 generated by the power outage signal generator 4 during the certain period T1 is multiplexed into the transmission signal 105 to be transmitted by the multiplexing circuit 7, and the output 10 of the communication device 1 is
6 to the opposing communication device 2.

FIG. 3 shows a receiving section of the communication device 2. As shown in FIG. In FIG. 3, a received signal 107 sent from the opposing communication device 1 is input to a power outage information detection section 8 and a communication stop determination section 9. The power outage information detection unit 8 searches for power outage information from the received signal 107, performs protection to improve detection accuracy, and then generates a power outage detection signal 108 at an average time T ₂ .

On the other hand, in the communication stop determination section 9, the received signal 1
07, and determines whether the communication between the communication devices is normal using, for example, means for determining frame synchronization or the presence or absence of a signal, and if the communication is interrupted, the communication stop detection signal 109 is sent at an average time of _T3 . occurs.

The first arrival determination unit 10 receives the power outage detection signal 108 and the communication stop detection signal 109, and determines which of these two signals occurred first in terms of time. Then, the power outage detection signal 108 is the communication stop detection signal 1
If it occurs earlier than 09, first-come-first-served judgment signal 1
10 is output as a logic "H" level, and conversely, if the communication stop detection signal 109 is early, a logic "L" level is output.

When the opposing communication device 1 has a power outage and sends power outage information, the timer circuit 16 receives the power outage detection signal 108 from the power outage information detection unit 8 and sets the time.
A delayed signal 111 is generated after T ₄ .

This delayed signal 111 is the first arrival determination signal 110.
and logic gate 11 (AND gate here)
The output of this logic gate 11 is input as a sampling signal 112 to the sampling section 12. The sampling unit 12 determines whether a communication stop occurs after time _T4 based on the sampling signal 112, and transmits the determination signal 113 to the latch circuit 13.
Output to.

On the other hand, the first-arrival determination signal 110 is passed through an inverting logic gate (inverter) to the communication stop determination prohibition signal 1.
15 and is input to the logic gate 15 (here, an AND gate) together with the communication stop detection signal 109. The output of this logic gate 15 is input to the latch circuit 13 as a communication stop determination signal 116.

The latch circuit 13 outputs a power failure determination signal 114 in response to the determination signal 113, and resets (inhibits) this power failure determination signal 114 in response to the communication stop determination signal 116.

The above-mentioned T ₁ to T ₄ are set as follows in the present invention.

Power failure detection time T ₂ < Power supply holding time T ₁ Power failure holding time T ₁ + Communication stoppage detection time T ₃ < Communication stoppage detection sampling time T ₄ Therefore, when a power outage occurs, the first-come-first-served judgment signal 110
is at “H” level, and the above-mentioned sampling section 12
inputs a communication stop determination signal 113 to the latch circuit 13 and outputs a power outage determination signal 114. At this time, the communication stop determination prohibition signal 115 goes to "L" level and suppresses the communication stop detection signal 109.

As described above, when a power outage occurs, a power outage determination is made based on the logic described above, while when characteristics of the transmission path between both communication devices deteriorate or a failure occurs in the transmission path, erroneous determination of a power outage is prohibited using the following logic.

That is, in the present invention, communication outage detection time T ₃ <power outage detection time T ₂ is set, and first-come-first-served determination unit 10 determines that communication outage occurs first, and first-come-first-served determination signal 110 is at logic “L” level. Output. Therefore, the sampling signal 112 is suppressed by the logic gate 11, and at the same time the communication stop judgment prohibition signal 115 is suppressed.
becomes "H" level, logic gate 15 outputs communication stop judgment signal 116, and resets the power failure judgment of latch circuit 13.

It goes without saying that the transmitting section of the communication device 2 and the receiving section of the communication device 1 are also configured as shown in FIGS. 2 and 3, respectively.

〔Effect of the invention〕

As explained above, the power outage detection method of the present invention is
The power outage information signal is multiplex transmitted from one communication device, and the other communication device determines whether the power outage information signal and the communication stop signal have arrived first, so it is the same as before. A time slot for power outage information is provided in the communication signal train between the communication devices, and if the power outage information bit is still sent to the other communication device, even if there is a failure between the communication devices, it will be incorrectly determined that the other communication device has experienced a power outage. This has the effect of stably detecting a power outage between communication devices without any effect on failure recovery.

[Brief explanation of the drawing]

Fig. 1 is a system configuration diagram between opposing communication devices showing an embodiment of the present invention, Fig. 2 is a block diagram for sending power outage information of the transmitter of the communication device on the side where a power outage occurs, and Fig. 3 1 is a block diagram for determining a power outage in a receiving section of an opposing communication device; FIG. DESCRIPTION OF SYMBOLS 1...Communication device (power outage side), 2...Communication device (opposite side), 3...Power outage detection unit, 4...Power outage signal generation unit, 5...Power supply holding unit, 6...Connector, 7... …
Multiple circuit, 8...Power failure information detection unit, 9...Communication stop determination unit, 10...First come first served determination unit, 11...Logic gate (AND gate), 12...Sampling unit,
13... Latch circuit, 14... Inverting logic gate (inverter), 15... Logic gate (AND gate), 16... Timer circuit.

Claims (1)

[Claims] 1. In communication devices facing each other, there is a means for detecting a power outage in the transmitter of one communication device, a means for maintaining the power necessary to secure communication for a certain period of time, and a means for detecting a power failure in the transmitting section of one communication device, and a means for maintaining the power supply necessary to secure communication for a certain period of time, and based on this detection, power outage detection means for detecting the power outage signal in a receiving section of the other communication device; communication stoppage detection means for detecting communication stoppage of the communication device; and both detection means. A power outage detection method comprising means for determining whether a detection signal from the power outage detection means arrives first, and means for outputting a power outage determination signal when a detection signal from the power outage detection means arrives first.