JP2017010229A - Communication device and communication system using the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce the possibility of erroneously obtaining data included in a communication signal.SOLUTION: A communication device 10 (slave unit 1) comprises a reception unit 11 and a control unit 13. The reception unit 11 is electrically connected with a pair of electric wires 41A and 41B, receives a communication signal S1 transmitted by a change of voltage Vt1 applied to between the pair of electric wires 41A and 41B, and outputs a reception signal corresponding to the communication signal S1. The control unit 13 monitors the presence or absence of a rising edge of the reception signal in a first determination period, monitors the presence or absence of a falling edge of the reception signal in a second determination period, thereby determines a bit in data included in the communication signal S1, and obtains the data. Then, the control unit 13 sets timing of each of the first determination period and the second determination period on the basis of the pulse width of a start bit in the reception signal.SELECTED DRAWING: Figure 1

Description

  The present invention generally relates to a communication device and a communication system using the communication device, and more particularly to a communication device that communicates with another communication device using a pair of electric wires as a medium and a communication system using the communication device.

  2. Description of the Related Art Conventionally, an automatic fire alarm system configured by connecting a fire detector to a sensor line derived from a fire receiver is known. The fire receiver of this automatic fire alarm system is configured to output a control signal to a fire detector via a sensor line. The fire detector is configured to execute an abnormality detection mode when receiving a control signal from the fire receiver.

JP 2002-8154 A

  In the automatic fire alarm system (communication system) as described above, for example, when the wiring of the sensor line becomes long, the resistance component and the capacitance component (capacity between the lines of the sensor line) of the sensor line increase. Then, due to the resistance component and the capacitance component of these sensor lines, the waveform (rising waveform and falling waveform) of the control signal (communication signal) may be lost. For this reason, the fire receiver (communication device) may erroneously acquire data included in the control signal.

  The present invention has been made in view of the above points, and an object thereof is to reduce the possibility of erroneously acquiring data included in a communication signal.

  The communication device of the present invention is electrically connected to a pair of electric wires, receives a communication signal transmitted by a change in voltage applied between the pair of electric wires, and outputs a reception signal corresponding to the communication signal. By monitoring the presence or absence of rising of the reception signal in the first determination period and the presence or absence of falling of the reception signal in a second determination period different from the first determination period, A control unit that determines a bit of data included in the communication signal and acquires the data, wherein the communication signal includes a start bit added to the head of the data, and the control unit includes the received signal The timing of each of the first determination period and the second determination period is set based on the pulse width of the start bit.

  The communication device of the present invention is electrically connected to a pair of electric wires, receives a communication signal transmitted by a change in voltage applied between the pair of electric wires, and outputs a reception signal corresponding to the communication signal. By monitoring the receiving unit and the presence or absence of the falling edge of the received signal in the first determination period, and monitoring the presence or absence of the rising edge of the reception signal in a second determination period different from the first determination period, A control unit that determines a bit of data included in the communication signal and acquires the data, wherein the communication signal includes a start bit added to the head of the data, and the control unit includes the received signal The timing of each of the first determination period and the second determination period is set based on the pulse width of the start bit.

  A communication system according to the present invention includes: a slave unit that is the above-described communication device; and a master unit that is electrically connected to the pair of electric wires and transmits the communication signal to the slave unit. .

  The present invention can reduce the possibility of erroneously acquiring data included in a communication signal.

It is a block diagram which shows schematic structure of the communication apparatus and communication system which concern on embodiment. 2A and 2B are operation explanatory diagrams of the communication device according to the embodiment, respectively. It is a block diagram which shows the whole structure of the communication system which concerns on embodiment. FIG. 4 is a waveform diagram of a communication signal and a received signal without waveform rounding in the communication system according to the embodiment. FIG. 5 is a waveform diagram of a communication signal and a reception signal having a rounded waveform in the communication system according to the embodiment. 6A and 6B are waveform diagrams illustrating examples of received signals in the communication system according to the embodiment. It is explanatory drawing which shows an example of operation | movement of the communication apparatus which concerns on embodiment. It is explanatory drawing which shows another example of operation | movement of the communication apparatus which concerns on embodiment. FIG. 9A and FIG. 9B are explanatory diagrams illustrating still another example of the communication device according to the embodiment.

  As shown in FIG. 1, the first configuration example of the communication device 10 (slave device 1) according to the embodiment of the present invention includes a receiving unit 11 and a control unit 13. The receiving unit 11 is electrically connected to the pair of electric wires 41A and 41B and receives a communication signal S1 transmitted by a change in voltage Vt1 (hereinafter referred to as “standby voltage”) applied between the pair of electric wires 41A and 41B. Received and outputs a received signal Rx1 corresponding to the communication signal S1.

  As shown in FIGS. 2A and 2B, the control unit 13 monitors whether the reception signal Rx1 rises during the first determination period T1, and determines whether the reception signal Rx1 falls during the second determination period T2. Monitor. And the control part 13 determines the bit of the data contained in the communication signal S1 by the determination result in these 1st determination period T1 and 2nd determination period T2, and acquires data. The second determination period T2 is different from the first determination period T1.

  Here, the communication signal S1 includes a start bit SB1 added to the head of the data.

  Then, the control unit 13 sets each timing of the first determination period T1 and the second determination period T2 based on the pulse width W0 of the start bit SB1 in the reception signal Rx1.

  Further, the second configuration example of the communication device 10 (slave device 1) according to the embodiment of the present invention is the above-described first configuration example, in which “rise” is set to “fall” and “fall” is set to “fall”. The configuration is read as “rise”.

  Moreover, the communication system 100 which concerns on embodiment of this invention is provided with the subunit | mobile_unit 1 which is the communication apparatus 10, and the main | base station 2 as shown in FIG. The base unit 2 is electrically connected to the pair of electric wires 41 </ b> A and 41 </ b> B and transmits a communication signal S <b> 1 to the handset 1.

  In the communication apparatus 10 and the communication system 100 of the present embodiment, the control unit 13 sets the timings of the first determination period T1 and the second determination period T2 according to the waveform rounding of the communication signal S1. Therefore, in the communication device 10 and the communication system 100 according to the present embodiment, the possibility of erroneously acquiring data included in the communication signal S1 can be reduced.

  Hereinafter, the communication device 10 and the communication system 100 according to the present embodiment will be described in detail. However, the configuration described below is merely an example of the present invention, and the present invention is not limited to the following embodiment, and the technical idea according to the present invention is not limited to this embodiment. Various changes can be made according to the design or the like as long as they do not deviate.

  Moreover, although the following description demonstrates the subunit | mobile_unit 1 of an automatic fire alerting | reporting system as the communication apparatus 10, it is not the meaning which limits the communication apparatus 10. FIG. Similarly, in the following description, the automatic fire alarm system is described as the communication system 100, but the communication system 100 is not intended to be limited.

<Overall configuration>
Below, the case where the communication system 100 of this embodiment is used for an apartment house (apartment) is illustrated. Of course, the communication system 100 according to the present embodiment is not limited to an apartment house, and may be used in various buildings such as commercial facilities, hospitals, hotels, and residential buildings.

  In the communication system 100 according to the present embodiment, as shown in FIG. 3, one master unit 2 and a plurality of slave units 101, 102, 103,... Yes. When each of the plurality of slave units 101, 102, 103... Is not particularly distinguished, it is simply referred to as “slave unit 1”.

  Furthermore, in this communication system 100, a pair of electric wires 41A and 41B are wired for each of the first to fourth floors. In short, two sets of two sets (two-wire type) of electric wires 41 </ b> A and 41 </ b> B are provided for the entire apartment house 5. In addition, the pair of electric wires 41 </ b> A and 41 </ b> B are electrically connected via the terminal resistor 3 at the end of the pair of electric wires 41 </ b> A and 41 </ b> B (the end opposite to the parent device 2). However, the termination resistor 3 is not an essential configuration and may be omitted.

  The basic configuration of the communication system 100 of the present embodiment is the same as a general automatic fire notification system. The communication system 100 is configured such that, for example, the occurrence of a fire is detected by the slave unit 1, and a fire occurrence notification (fire report) is made from the slave unit 1 to the master unit 2. In addition, the subunit | mobile_unit 1 may be the structure containing not only the structure which detects generation | occurrence | production of a fire but a transmitter etc., for example. The transmitter means, for example, a device that has a push button switch and notifies the parent device 2 of the occurrence of a fire by manually operating the push button switch when a person detects a fire.

  In addition, the communication system 100 according to the present embodiment allows other devices such as smoke prevention facilities and emergency broadcasting facilities to be connected when the parent device 2 receives a notification (interlocking report) for linking other devices. Has an interlocking function for interlocking. Therefore, the communication system 100 according to the present embodiment can control the fire door of the smoke evacuation facility or notify the occurrence of the fire by sound or voice in the emergency broadcasting facility when a fire occurs. is there.

By the way, as an automatic fire alarm system, there are generally a P-type (Proprietary-type) automatic fire alarm system and an R-type (Record-type) automatic fire alarm system. The P-type automatic fire notification system is configured such that the slave unit notifies the master unit of the occurrence of a fire by short-circuiting the pair of electric wires. The R-type automatic fire alarm system is configured such that a slave unit notifies the master unit of a fire by communication.

  The communication system 100 of this embodiment is based on a P-type automatic fire alarm system. In the communication system 100 of the present embodiment, the existing wiring (the pair of electric wires 41A and 41B installed for each floor) is used as it is in the apartment house 5 where the P-type automatic fire alarm system has been introduced. The case where the main | base station 2 and the several subunit | mobile_unit 1 are replaced is assumed. In addition, the communication system 100 of this embodiment can also be employ | adopted as an automatic fire alarm system introduced newly.

  Hereinafter, the configuration of the master unit 2 and the plurality of slave units 1 (communication device 10) will be described in detail. In the following description, only one slave unit 1 among the plurality of slave units 1 will be described, and the remaining slave units 1 have the same configuration as the single slave unit 1, and thus description thereof will be omitted. .

<Configuration of base unit>
The master unit 2 is a P-type receiver that receives a notification of fire occurrence (fire report) and a notification (link report) for interlocking other devices from the slave unit 1. Base unit 2 is installed in a management room of a building (apartment house 5).

  As shown in FIG. 1, the master unit 2 includes an application unit 21, a resistor 22, a reception unit 23, a transmission unit 24, a display unit 25 that performs various displays, and an operation that receives an operation input from a user. The unit 26 and a control unit 27 that controls each unit are provided.

  The application unit 21 applies a predetermined voltage to the pair of electric wires 41A and 41B. Here, as an example, the voltage applied between the pair of electric wires 41A and 41B by the applying unit 21 is 24V DC, but the present invention is not limited to this value.

  The resistor 22 is connected between the applying unit 21 and at least one of the pair of electric wires 41A and 41B. In the example of FIG. 1, the resistor 22 is inserted between one (high potential side) electric wire 41 </ b> A of the pair of electric wires 41 </ b> A and 41 </ b> B and the application unit 21. However, not limited to this example, the resistor 22 may be inserted between the other (low potential side) electric wire 41B and the applying unit 21, or both of the pair of electric wires 41A and 41B and the applying unit 21. Between them.

  The resistor 22 has a first function of converting a current flowing through the resistor 22 into a potential difference (voltage) between both ends of the resistor 22 by a voltage drop, and a pair of wires 41A when the pair of wires 41A and 41B is short-circuited. , 41B, and a second function for limiting the current flowing through 41B. In short, the resistor 22 has a first function as a current-voltage conversion element and a second function as a current limiting element. Here, as an example, the resistance value of the resistor 22 is 470Ω, but the value is not limited to this value.

  The receiving unit 23 is electrically connected between the resistor 22 and the pair of electric wires 41A and 41B. The receiving part 23 receives the communication signal S2 transmitted from the subunit | mobile_unit 1 based on the voltage (standby voltage) Vt1 between a pair of electric wires 41A and 41B. Specifically, when the handset 1 draws in the current flowing through the pair of electric wires 41A and 41B as will be described later, the current value of the current flowing through the resistor 22 changes and the standby voltage Vt1 changes. The receiving unit 23 receives the communication signal S2 transmitted from the child device 1 by detecting the voltage value of the standby voltage Vt1. In addition, the receiving unit 23 receives a fire report (described later) and a linked report (described later) notified from the slave unit 1 by detecting the voltage value of the standby voltage Vt1.

  The transmission unit 24 is electrically connected between the resistor 22 and the pair of electric wires 41A and 41B. The transmission part 24 transmits the communication signal S1 to the subunit | mobile_unit 1 by changing the electric current which flows through a pair of electric wire 41A, 41B. Specifically, when the transmission unit 24 draws a current flowing from the application unit 21 to the resistor 22, the standby voltage Vt1 changes. That is, the transmission unit 24 transmits the communication signal S1 to the child device 1 by changing the standby voltage Vt1 by drawing the current flowing from the application unit 21 to the resistor 22.

  In the communication system 100 of this embodiment, the control unit 27 controls the transmission unit 24 to alternately switch the voltage value of the standby voltage Vt1 between the first level V1 and the second level V2 (<V1). The signal S1 is transmitted to the child device 1 (see FIG. 4A).

  The display unit 25 includes, for example, an LED (Light Emitting Diode), a liquid crystal display, an organic electroluminescence display, and the like. The display part 25 displays the content according to the data contained in the communication signal S2 received from the subunit | mobile_unit 1 by being controlled by the control part 27. FIG. The display unit 25 displays, for example, the occurrence of a fire and the floor (floor) where the fire occurred. Moreover, the display part 25 can also display the installation place of the said subunit | mobile_unit 1 when the specific identification information (for example, address) of the subunit | mobile_unit 1 which detected the fire can be acquired.

  The control unit 27 has a microcomputer (microcomputer) as a main component, and implements a desired function by executing a program stored in a memory. The program may be written in the memory in advance, but may be provided by being stored in a recording medium such as a memory card, or may be provided through an electric communication line.

  As described above, the base unit 2 applies the voltage between the pair of electric wires 41A and 41B from the applying unit 21, thereby including the slave unit 1 connected to the pair of electric wires 41A and 41B. Functions as a power source for operation.

  Furthermore, the base unit 2 further includes a standby power source 28 using a storage battery so that a power source for operation of the communication system 100 can be secured even in the event of a power failure. The main unit 2 uses a commercial power source, a private power generation facility, or the like as a main power source. The application unit 21 automatically switches the power supply source from the main power source to the standby power source 28 when the main power source is interrupted, and automatically switches from the standby power source 28 to the main power source when the main power source is restored.

<Configuration of slave unit>
As shown in FIG. 1, the slave unit 1 (communication device 10) includes a reception unit 11, a transmission unit 12, a control unit 13, a diode bridge (DB) 14, a power supply unit 15, and a sensor 16. And a storage unit 17.

  In the diode bridge 14, a pair of electric wires 41 </ b> A and 41 </ b> B are electrically connected to an input end, and a reception unit 11, a transmission unit 12, and a power supply unit 15 are electrically connected to an output end.

  The power supply part 15 produces | generates the electric power for operation | movement of the subunit | mobile_unit 1 by supplying electric power from a pair of electric wire 41A, 41B.

  The sensor 16 detects the occurrence of fire or smoke, for example, by detecting a change in smoke concentration, a change in temperature, or a change in gas concentration such as carbon monoxide. The detection result of the sensor 16 is input to the control unit 13.

  The receiving unit 11 receives the communication signal S1 transmitted from the parent device 2 based on the change in the standby voltage Vt1. Specifically, when the base unit 2 draws the current flowing through the pair of electric wires 41A and 41B, the current value of the current flowing through the resistor 22 changes, and the standby voltage Vt1 changes. The receiving unit 11 receives the communication signal S1 transmitted from the parent device 2 by detecting the voltage value of the output voltage Vr1 of the diode bridge 14 corresponding to the standby voltage Vt1.

  The transmission unit 12 is electrically connected to the pair of electric wires 41A and 41B. The transmission part 12 transmits the communication signal S2 to the main | base station 2 by changing the electric current which flows through a pair of electric wire 41A, 41B. Specifically, when the transmission unit 12 draws a current flowing through the pair of electric wires 41A and 41B, the standby voltage Vt1 changes. That is, the transmission unit 12 transmits the communication signal S2 to the parent device 2 by changing the voltage (standby voltage) Vt1 between the pair of wires 41A and 41B by drawing the current flowing through the pair of wires 41A and 41B. .

  The control unit 13 controls the reception unit 11 and the transmission unit 12. The control unit 13 adjusts the amount of current drawn according to the output of the sensor 16 to cause the transmission unit 12 to transmit the communication signal S2 to the base unit 2, or the communication unit S1 receives the communication signal S1 from the base unit 2. To receive. Here, the control unit 13 has a microcomputer as a main component, and implements a desired function by executing a program stored in a memory. The program may be written in the memory in advance, but may be provided by being stored in a recording medium such as a memory card, or may be provided through an electric communication line.

  The control unit 13 periodically reads the output (sensor value) of the sensor 16 and determines that a fire occurs when the output of the sensor 16 exceeds the first reference value. And the control part 13 changes the standby voltage Vt1 to a fire alert level by controlling the transmission part 12 and adjusting the drawing-in amount of the electric current which flows through a pair of electric wire 41A, 41B. Thereby, the control part 13 notifies the main | base station 2 of a fire report.

  In addition, when the output of the sensor 16 exceeds the second reference value (> first reference value), the control unit 13 determines that the other device is linked. Then, the control unit 13 controls the transmission unit 12 to adjust the amount of current drawn through the pair of electric wires 41A and 41B, thereby changing the standby voltage Vt1 to the interlocking reporting level (<fire reporting level). Thereby, the control unit 13 notifies the master unit 2 of the linked information.

  In addition, the control unit 13 controls the transmission unit 12 to communicate with the parent device 2 by alternately switching the voltage value of the standby voltage Vt1 between the first level V1 and the second level V2 (<first level). Signal S2 is transmitted. The communication signal S2 includes, for example, information (identification information) for specifying the issue source for each slave unit, information for automatic testing, and the like. The items of the automatic test include, for example, survival confirmation (keep alive), self-diagnosis of the slave unit 1 and the like.

  The storage unit 17 stores at least identification information (for example, an address) assigned in advance to the child device 1. That is, unique identification information is assigned to each of the plurality of slave units 101, 102, 103. Each identification information is registered in the master unit 2 in association with each installation location (for example, a room number) of the plurality of slave units 101, 102, 103.

<Reception of communication signal>
Hereinafter, reception of the communication signal S1 by the subunit | mobile_unit 1 (communication apparatus 10) is demonstrated in detail. The receiving unit 11 compares the voltage value of the output voltage Vr1 of the diode bridge 14 with the voltage value of the threshold voltage Vs1, thereby receiving the communication signal S1 and outputting the received signal Rx1 corresponding to the communication signal S1. Specifically, as illustrated in FIG. 4, the reception unit 11 receives the low level (“L” illustrated in FIG. 4) received signal Rx <b> 1 if the voltage value of the output voltage Vr <b> 1 exceeds the voltage value of the threshold voltage Vs <b> 1. Is output. Further, the receiving unit 11 outputs a reception signal Rx1 of a high level (“H” shown in FIG. 4) if the voltage value of the output voltage Vr1 is equal to or lower than the voltage value of the threshold voltage Vs1. The reception unit 11 receives a high level signal if the voltage value of the output voltage Vr1 exceeds the voltage value of the threshold voltage Vs1, and receives a low level signal if the voltage value of the output voltage Vr1 is equal to or less than the voltage value of the threshold voltage Vs1. It may be configured to output Rx1.

  And the control part 13 acquires the data contained in communication signal S1 by processing receiving signal Rx1. For example, the control unit 13 samples the reception signal Rx1 for each bit period BT1 (see FIG. 4) of the communication signal S1, thereby converting the reception signal Rx1 into binary values “0” and “1”. It is conceivable to acquire. That is, when the reception signal Rx1 changes to low level, high level, low level, and high level for each bit cycle BT1 of the communication signal S1, the control unit 13 acquires the reception signal Rx1 as 4-bit data “0101”. To do.

<Shape of communication signal waveform>
Here, in the communication system 100 of this embodiment, when the wiring of the pair of electric wires 41A and 41B becomes longer, the resistance component and the capacitance component (interline capacitance) of the pair of electric wires 41A and 41B increase. Then, due to the resistance component and the capacitance component of the pair of electric wires 41A and 41B, the waveforms (the rising waveform and the falling waveform) of the output voltage Vr1 and the communication signal S1 may be rounded.

  For example, in the slave unit 1 at a position away from the master unit 2 in the communication system 100 of the present embodiment, the waveforms of the output voltage Vr1 and the communication signal S1 are rounded by the resistance component and the capacitance component of the pair of electric wires 41A and 41B. (See FIG. 5). In this case, the reception unit 11 outputs a reception signal Rx1 having a high level and a short pulse width as compared with the case where the output voltage Vr1 without waveform rounding is input.

  When the output voltage Vr1 and the communication signal S1 have rounded waveforms as described above, the control unit 13 uses the technique of sampling the reception signal Rx1 for each bit cycle BT1 of the communication signal S1 as described above. There is a possibility that data of will be obtained by mistake. For example, it is assumed that data included in the communication signal S1 is 4-bit “0101”. Then, it is assumed that the reception unit 11 outputs the reception signal Rx1 having a waveform as shown in FIG. 6A due to the waveform rounding of the output voltage Vr1 and the communication signal S1. In this case, since the high-level pulse width W1 of the reception signal Rx1 is longer than the bit period BT1 of the communication signal S1, the control unit 13 erroneously acquires “1” of 1 bit as “11” of 2 bits. there's a possibility that.

  Further, it is assumed that data included in the communication signal S1 is 4-bit “0110”. Then, it is assumed that the reception unit 11 outputs a reception signal Rx1 having a waveform as shown in FIG. 6B based on the waveform rounding of the output voltage Vr1 and the communication signal S1. In this case, since the high-level pulse width W2 of the reception signal Rx1 has substantially the same length as the bit cycle BT1 of the communication signal S1, the control unit 13 sets “11” of 2 bits as “1” of 1 bit. There is a possibility of getting it by mistake.

<Judgment period>
Therefore, in the handset 1 (communication device 10) of the present embodiment, the control unit 13 is configured as follows. That is, the control unit 13 is configured to monitor whether or not the reception signal Rx1 rises during the first determination period T1 (see FIG. 2A). Further, the control unit 13 is configured to monitor whether or not the reception signal Rx1 falls in a second determination period T2 (see FIG. 2A) different from the first determination period T1. And the control part 13 is comprised so that the bit of the data contained in communication signal S1 may be determined by the determination result in these 1st determination period T1 and 2nd determination period T2, and data may be acquired.

  Furthermore, the control unit 13 is configured to set the timings of the first determination period T1 and the second determination period T2 based on the pulse width W0 of the start bit SB1 in the reception signal Rx1. The start bit SB1 is included in the communication signal S1, and is added to the head of the data.

  That is, the control unit 13 estimates the degree of waveform rounding of the output voltage Vr1 and the communication signal S1 based on the pulse width W0 of the start bit SB1. Then, the control unit 13 sets the first determination period T1 and the second determination period T2 at the timing at which the rising / falling of the reception signal Rx1 occurs based on the degree of waveform rounding.

  Hereinafter, the process in which the control unit 13 of the slave unit 1 (communication device 10) acquires the data of the communication signal S1 will be described in detail. First, when receiving the reception signal Rx1 from the reception unit 11, the control unit 13 calculates the pulse width W0 of the start bit SB1 included in the reception signal Rx1. Specifically, the control unit 13 calculates the pulse width W0 of the start bit SB1 by measuring the time required from the time t1 when the start bit SB1 rises to the time t2 when the start bit SB1 falls (FIG. 2A). reference).

  Next, the control unit 13 uses the pulse width W0 of the start bit SB1 to calculate the timings of the first determination period T1 and the second determination period T2 by the following equations (1) and (2). In each of the following expressions (1) and (2), “n” represents the number of times of the first determination period T1 (or the second determination period T2). In each of the following equations (1) and (2), “α” is the value of the bit period BT1 of the communication signal S1, “β” is the value of the pulse width W0 of the start bit SB1 of the received signal Rx1, and “γ”. Represents an allowable error in consideration of variation of the threshold voltage Vs1.

n · α + (α−β) ± γ (1)
n · α− (α−β) ± γ (2)
For example, it is assumed that α = 800 [μs] and γ = 300 [μs]. Further, for example, as shown in FIG. 2A, it is assumed that there is no waveform rounding in the output voltage Vr1 and the communication signal S1. In this case, since the pulse width W0 of the start bit SB1 of the reception signal Rx1 is equal to the bit period BT1 of the communication signal S1, β = 800 [μs]. Therefore, both the first determination period T1 and the second determination period T2 are represented by 800 · n ± 300 [μs].

  That is, in the above case, the first (n = 1) first determination period T1 starts from the falling edge of the start bit SB1 of the reception signal Rx1 (or the falling edge of the reception signal Rx1), and is 500 to 1100 [μs]. Set between. The second (n = 2) first determination period T1 is set between 1300 and 1900 [μs], starting from the falling edge of the start bit SB1 of the received signal Rx1 (or the falling edge of the received signal Rx1). Is done.

  Similarly, the first (n = 1) second determination period T2 is set between 500 and 1100 [μs] starting from the rising edge of the reception signal Rx1. The second (n = 2) second determination period T2 is set between 1300 and 1900 [μs], starting from the rising edge of the reception signal Rx1.

  On the other hand, for example, as shown in FIG. 2B, assuming that the output voltage Vr1 and the communication signal S1 have waveform rounding, the pulse width W0 of the start bit SB1 of the reception signal Rx1 is shorter than the bit period BT1 of the communication signal S1. Become (or become longer). Here, it is assumed that β = 300 [μs]. In this case, the first determination period T1 is represented by 800 · n + 500 ± 300 [μs], and the second determination period T2 is represented by 800 · n−500 ± 300 [μs].

  That is, in the above case, the first (n = 1) first determination period T1 starts at the falling edge of the start bit SB1 of the reception signal Rx1 (or the falling edge of the reception signal Rx1), and starts at 1000 to 1600 [μs]. Set between. The second (n = 2) first determination period T1 is set between 1800 and 2400 [μs], starting from the falling edge of the start bit SB1 of the received signal Rx1 (or the falling edge of the received signal Rx1). Is done.

  Similarly, the first (n = 1) second determination period T2 is set between 0 and 600 [μs] starting from the rising edge of the reception signal Rx1. The second (n = 2) second determination period T2 is set between 800 and 1400 [μs], starting from the rising edge of the reception signal Rx1.

  Here, the first determination period T1 is set with the falling edge of the start bit SB1 (or the falling edge of the reception signal Rx1) as the starting point, but may be set with another timing as the starting point. For example, the first determination period T1 may be set starting from the rising edge of the start bit SB1 (or the rising edge of the reception signal Rx1).

  And the control part 13 determines the bit of the data of communication signal S1, and acquires data using 1st determination period T1 and 2nd determination period T2. For example, when detecting the rising edge of the reception signal Rx1 in the first (n = 1) first determination period T1, the control unit 13 determines 1-bit “0”. On the other hand, when the rising of the received signal Rx1 is not detected in the first determination period T1 for the first time, the control unit 13 monitors the presence or absence of the rising of the received signal Rx1 in the second (n = 2) first determination period T1. To do. And the control part 13 will determine with "00" of 2 bits, if the rising of received signal Rx1 is detected in the said period. That is, when the control unit 13 detects the rising edge of the reception signal Rx1 in the n-th first determination period T1, the control unit 13 determines that “0” is n-bit continuous data.

  When detecting the rising edge of the reception signal Rx1 in the first determination period T1, the control unit 13 monitors the presence or absence of the falling edge of the reception signal Rx1 in the second determination period T2, using the rising time as a starting point. Similarly to the above, when the control unit 13 detects the falling edge of the reception signal Rx1 in the n-th second determination period T2, the control unit 13 determines that “1” is data having n bits in succession. Then, when detecting the falling edge of the reception signal Rx1 in the second determination period T2, the control unit 13 determines whether or not the reception signal Rx1 has risen next in the first determination period T1, starting from this falling time. Monitor.

  The control unit 13 repeats the above process to determine the data bit of the communication signal S1 and acquire the data. Here, since the control unit 13 monitors whether or not the reception signal Rx1 rises only during the first determination period T1, the rise of the reception signal Rx1 at a timing other than the first determination period T1 is ignored as noise. Similarly, the control unit 13 monitors the presence / absence of the fall of the reception signal Rx1 only in the second determination period T2. Therefore, the fall of the reception signal at timings other than the second determination period T2 is ignored as noise.

  Hereinafter, specific examples assuming that the data included in the communication signal S1 is 7-bit “0010110” are shown in FIGS. 2A and 2B. As described above, FIG. 2A shows a case where no waveform rounding exists in the output voltage Vr1 and the communication signal S1, and FIG. 2B shows a case where waveform rounding exists in the output voltage Vr1 and the communication signal S1. Is shown. Accordingly, the timing of each of the first determination period T1 and the second determination period T2 is different between the case shown in FIG. 2A and the case shown in FIG. 2B. Therefore, the values of time t1 to time t20 shown in FIG. This is different from the values of time t1 to time t20 shown in 2B.

  In the case shown in FIG. 2B, the second determination period T2 to be set between time t8 and time t9 has its start point before the end point (time t6) of the immediately preceding first determination period T1. Here, it is set between time t6 and time t9. Similarly, the second determination period T2 to be set between time t14 and time t15 has its start point before the end point (time t12) of the immediately preceding first determination period T1, so here the time t12 to It is set during time t15.

  In either case of FIG. 2A or FIG. 2B, the control unit 13 sets the received signal Rx1 in the first determination period T1 (time t3 to time t4) for the first time starting from the end point (time t2) of the start bit SB1. Does not detect rising edge. Then, the control unit 13 detects the rising edge of the reception signal Rx1 in the second first determination period T1 (time t5 to time t6). That is, the control unit 13 determines “00” of 2 bits at this time. Further, the control unit 13 receives the signal at the first second determination period T2 (time t8 to time t9 in FIG. 2A, time t6 to time t9 in FIG. 2B) with the rising edge of the reception signal Rx1 as the start point (time t7). The falling edge of the signal Rx1 is detected. That is, the control unit 13 further determines “1” of 1 bit at this time. Further, the control unit 13 detects the rising edge of the reception signal Rx1 in the first first determination period T1 (time t11 to time t12) with the falling edge of the reception signal Rx1 as the start point (time t10). That is, the control unit 13 further determines 1-bit “0” at this time.

  Further, the control unit 13 receives signals in the first second determination period T2 (time t14 to time t15 in FIG. 2A, time t12 to time t15 in FIG. 2B) with the rising edge of the reception signal Rx1 as the start point (time t13). The falling edge of the signal Rx1 is not detected. Then, the control unit 13 detects the falling edge of the reception signal Rx1 in the second second determination period T2 (time t16 to time t17). That is, the control unit 13 further determines “1” of 2 bits at this time. Then, the control unit 13 does not detect the falling edge of the reception signal Rx1 in the first first determination period T1 (time t19 to time t20) with the falling edge of the reception signal Rx1 as the starting point (time t18). That is, the control unit 13 determines 1-bit “0” at this time.

  By processing the reception signal Rx1 as described above, the control unit 13 correctly acquires 7-bit “0010110” as data included in the communication signal S1 in both cases of FIG. 2A and FIG. 2B. Can do.

  As described above, in the slave unit 1 (communication device 10) of the present embodiment, the control unit 13 monitors whether the reception signal Rx1 rises or falls during the first determination period T1 and the second determination period T2. Thus, the bit of data included in the communication signal S1 is determined. Further, the control unit 13 calculates the pulse width W0 of the start bit SB1 of the reception signal Rx1, thereby determining the timing of each of the first determination period T1 and the second determination period T2 and the waveform of the output voltage Vr1 and the communication signal S1. The timing is set according to the rounding. For this reason, in the subunit | mobile_unit 1 (communication apparatus 10) of this embodiment, possibility that the data contained in communication signal S1 will be acquired accidentally can be reduced.

  By the way, in the subunit | mobile_unit 1 (communication apparatus 10) of this embodiment, the control part 13 is each timing of 1st determination period T1 and 2nd determination period T2 based on pulse width W0 of start bit SB1 of communication signal S1. However, other configurations may be used. For example, the controller 13 may be configured to update the timings of the first determination period T1 and the second determination period T2 based on the bit width W11 of the determined data in the reception signal Rx1.

  Hereinafter, specific examples will be described. As shown in FIG. 7, the control unit 13 detects the rising edge of the reception signal Rx1 in the first determination period T1 starting from the end point of the start bit SB1, and then rises the reception signal Rx1 in the second determination period T2. Assume that a fall has been detected. In this case, the control unit 13 calculates the bit width W11 of the determined data by measuring the time required from the time t21 when the reception signal Rx1 rises to the time t22 when the reception signal Rx1 falls.

  And the control part 13 updates each timing of 1st determination period T1 and 2nd determination period T2 by Formula (1), (2) using the bit width W11 of this determined data. In FIG. 7, the updated first determination period T1 is indicated by “T11”, and the updated second determination period T2 is indicated by “T12”. Hereinafter, every time the bit width of the determined data is calculated, the control unit 13 updates the timing of each of the first determination period T1 and the second determination period T2.

  In this configuration, the timing of each of the first determination period T1 and the second determination period T2 is sequentially updated each time a data bit is determined, so that the control unit 13 is more accurately included in the communication signal S1. Data can be acquired.

  Moreover, the subunit | mobile_unit 1 (communication apparatus 10) of this embodiment may be provided with the following structures. That is, the control unit 13 may be configured to determine a bit of data by ignoring a pulse shorter than a predetermined pulse width in the reception signal Rx1.

  Hereinafter, specific examples will be described. As shown in FIG. 8, it is assumed that noise N1 having a pulse width W12 is generated in the output voltage Vr1 or the communication signal S1. Then, the reception unit 11 outputs a reception signal Rx1 reflecting this noise N1.

  On the other hand, it is assumed that the controller 13 detects the rising edge of the noise N1 as the rising edge of the reception signal Rx1 in the first determination period T1. Then, before determining the data bit, the control unit 13 measures the time from the time t31 when the rising edge of the reception signal Rx1 is detected to the time when the reception signal Rx1 falls next time. Here, the control unit 13 detects the falling edge of the noise N1 as the falling edge of the reception signal Rx1 at time t32.

  Then, if the time required from time t31 to time t32 (that is, the pulse width W12 of the noise N1) is shorter than the predetermined pulse width, the control unit 13 causes the rising and falling edges of the received signal Rx1 to be pulsed by the noise N1. Ignore it. That is, the control unit 13 filters the noise N1 and determines a bit of data included in the communication signal S1.

  Although the case where the rising edge of the noise N1 is detected in the first determination period T1 has been described here, the control unit 13 performs the same process as described above even when the falling edge of the noise N1 is detected in the second determination period T2. Run.

  In this configuration, even if the noise N1 occurs in the output voltage Vr1 or the communication signal S1, the control unit 13 can determine the bit of data included in the communication signal S1 without being affected by the noise N1.

  Moreover, the subunit | mobile_unit 1 (communication apparatus 10) of this embodiment may be provided with the following structures. That is, when the control unit 13 cannot detect the next change in the reception signal Rx1 even after measuring the predetermined time T3 after detecting the change (rise or fall) in the reception signal Rx1, the control unit 13 changes the standby voltage Vt1. The communication signal S1 may not be acquired.

  In this configuration, it is assumed that the communication signal S1 is Manchester encoded. That is, the receiving unit 11 outputs a Manchester-encoded received signal Rx1 as shown in FIG. 9A.

  Here, the Manchester-encoded received signal Rx1 always transitions from the low level to the high level or from the high level to the low level even when “0” or “1” continues. Therefore, in such a received signal Rx1, for example, when a low level or high level period continues for a length corresponding to 3 bits or more, it is considered that a communication error has occurred.

  Therefore, for example, as shown in FIG. 9B, the control unit 13 measures a predetermined time T3 from the time t41 when detecting the change (falling) of the reception signal Rx1 at the time t41. If the next change (rise) of the reception signal Rx1 is not detected at the time t42 when the predetermined time T3 has elapsed, the control unit 13 does not acquire the change in the standby voltage Vt1 as the communication signal S1.

  In this configuration, the control unit 13 does not acquire the change in the standby voltage Vt1 as the communication signal S1 when any communication error occurs, so that the communication signal S1 can be prevented from being erroneously acquired. In addition, in this configuration, when the standby voltage Vt1 changes to the fire alarm level or the interlocking alarm level when the other slave unit 1 notifies the master unit 2 of the fire alarm or the interlocking alarm, the change of the standby voltage Vt1 is also achieved. Can be prevented from being erroneously acquired as the communication signal S1.

  In the above description, the state in which the received signal Rx1 transitions from the low level to the high level is “1”, and the state in which the reception signal Rx1 transitions from the high level to the low level is “0”. That is, the state in which the reception signal Rx1 transitions from the high level to the low level may be “1”, and the state in which the reception signal Rx1 transitions from the low level to the high level may be “0”.

  By the way, in the subunit | mobile_unit 1 (communication apparatus 10) of this embodiment, the control part 13 monitors the presence or absence of the rising of received signal Rx1 in 1st determination period T1, and falls of received signal Rx1 in 2nd determination period T2. However, other configurations may be used. For example, the control unit 13 may be configured to monitor whether or not the reception signal Rx1 falls in the first determination period T1, and monitor whether or not the reception signal Rx1 rises in the second determination period T2.

  Moreover, in the communication system 100 of this embodiment, although the subunit | mobile_unit 1 is the communication apparatus 10, the main | base station 2 may be the communication apparatus 10, and both the subunit | mobile_unit 1 and the main | base station 2 are the communication apparatuses 10. It may be. When the parent device 2 is the communication device 10, the receiving unit 23 of the parent device 2 receives the communication signal S2 and outputs a reception signal corresponding to the communication signal S2. Then, the control unit 27 of the base unit 2 monitors the presence / absence of rising / falling of the received signal in the first determination period T1 and the second determination period T2, respectively, so that the bit of data included in the communication signal S2 is obtained. Judge and get data. Further, the control unit 27 sets the timings of the first determination period T1 and the second determination period T2 based on the pulse width W0 of the start bit SB1 of the received signal.

  Note that the operations of the receiving unit 23 and the control unit 27 of the parent device 2 are the same as the operations of the receiving unit 11 and the control unit 13 of the child device 1, respectively, and thus description thereof is omitted here.

1 slave unit 2 master unit 10 communication device 11 receiving unit 13 control unit 41A, 41B pair of wires 100 communication system Rx1 received signal S1 communication signal SB1 start bit T1 first determination period T2 second determination period T3 predetermined time Vt1 voltage ( Standby voltage)
W0 pulse width W11 bit width

Claims (6)

A receiving unit electrically connected to the pair of electric wires, receiving a communication signal transmitted by a change in voltage applied between the pair of electric wires, and outputting a reception signal corresponding to the communication signal;
By monitoring the presence or absence of rising of the reception signal in the first determination period and monitoring the presence or absence of falling of the reception signal in a second determination period different from the first determination period, A control unit for determining a bit of data included and acquiring the data;
The communication signal includes a start bit added to the head of the data,
The communication unit is characterized in that the timing of each of the first determination period and the second determination period is set based on a pulse width of the start bit in the received signal. A receiving unit electrically connected to the pair of electric wires, receiving a communication signal transmitted by a change in voltage applied between the pair of electric wires, and outputting a reception signal corresponding to the communication signal;
By monitoring the presence or absence of the falling edge of the received signal in the first determination period and monitoring the presence or absence of the rising edge of the received signal in a second determination period different from the first determination period, A control unit for determining a bit of data included and acquiring the data;
The communication signal includes a start bit added to the head of the data,
The communication unit is characterized in that the timing of each of the first determination period and the second determination period is set based on a pulse width of the start bit in the received signal.   The said control part updates the timing of each of the said 1st determination period and the said 2nd determination period based on the bit width of the said data determined in the said received signal, The Claim 1 or 2 characterized by the above-mentioned. Communication device.   4. The communication apparatus according to claim 1, wherein the control unit determines a bit of the data by ignoring a pulse shorter than a predetermined pulse width in the received signal. 5. The communication signal is Manchester encoded;
When the control unit cannot detect the next change in the received signal even after measuring a predetermined time after detecting the change in the received signal, the control unit detects the change in the voltage applied between the pair of wires. The communication device according to claim 1, wherein the communication device is not acquired as a signal. A handset which is the communication device according to any one of claims 1 to 5,
A communication system comprising: a master unit electrically connected to the pair of electric wires and transmitting the communication signal to the slave unit.

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