JPH0450782B2 - - Google Patents

Description

[Detailed Description of the Invention] [Objective of the Invention] (Industrial Application Field) This invention is used, for example, in an air conditioner having a plurality of indoor units, and is intended to provide mutual communication between two devices connected by an AC power line. The present invention relates to a serial data transfer device that transmits and receives serial data.

(Prior Art) A conventional device of this type was constructed as shown in FIG. 1 or 2.

That is, in the apparatus of FIG. 1, one side (hereinafter referred to as
In addition to the power supply line AC, two serial signal lines SL are provided between the device 1 on the transmitting side (hereinafter referred to as the receiving side) and the device 2 on the other side (hereinafter referred to as the receiving side). ), data was sent and received alternately in time division.

However, with this device, not only was the connection between devices 1 and 2 complicated with four wires, but the voltage levels on the transmitting and receiving sides were different, and incorrect wiring could lead to destruction of the device. .

Furthermore, in the device shown in FIG. 2, device 1 and device 2 are connected by a power line AC, and serial data is transmitted and received using this single power line.

In other words, the serial signal is modulated by the modulation circuit 3 on the transmitting side.
The receiving side takes out the modulated signal from the power line AC, and demodulates it in the demodulation circuit 4 to obtain data.

This device serves as both a signal line and a power supply line, so there is no need to worry about wiring, but each of the devices 1 and 2 requires a modulation circuit 3 and a demodulation circuit 4 with complex circuit configurations, which are expensive and expensive. Ta.

(Problems to be Solved by the Invention) As described above, conventional serial data transfer devices have problems in that there are many connections, incorrect wiring may damage the device, and the circuit configuration required for transmission and reception becomes complicated. It was hot.

(Means for Solving the Problems) The present invention provides two devices connected by an AC power line, one signal line provided between each device, and one signal line provided on one side of each device to transfer data. between one of the AC power lines and the signal line on one side of each device; a first serial data signal generating means that is connected to the transfer data signal and turns on and off during a positive half cycle period of the AC power supply voltage to create a serial data signal based on the positive half cycle signal of the AC power supply voltage; a first detection means connected between one of the AC power supply lines and the signal line on one side of each device and detecting a half-cycle signal flowing through the signal line during a negative half-cycle period of the AC power supply voltage; a second transfer data signal generating means for generating a transfer data signal corresponding to the transfer data provided on the other side of the device and in which one bit is synchronized with one cycle of the AC power supply voltage; It is connected between the other line and the signal line and turns on and off during the negative half cycle period of the AC power supply voltage in accordance with the transfer data signal to create a serial data signal based on the negative half cycle signal of the AC power supply voltage. a second serial data signal generation means, which is connected between the other AC power supply line and the signal line on the other side of each device, and generates a half-cycle signal that flows through the signal line during a positive half-cycle period of the AC power supply voltage; The serial data transfer device includes a second detection means for detecting the serial data.

(Function) According to such a configuration, serial data is transferred from one device to the other device via a single signal line by a positive half-cycle signal, and from the other device by a negative half-cycle signal. The signal transfers serial data to one device, allowing mutual transmission and reception.

(Example) Hereinafter, an example of the present invention will be described with reference to the drawings.

In FIG. 3, a device 1 and a device 2 are connected by an alternating current power line AC, and one signal line SL is provided between the devices 1 and 2.

The device 1 is provided with a control circuit 10, a first serial data signal generation circuit 11 ₁ , and a first detection circuit 13 ₁ .

The control circuit 10 has a first transfer data signal generating means, and generates transfer data corresponding to data to be transferred (hereinafter referred to as transfer data), in which one bit is synchronized with one cycle of the AC power supply voltage. Create a signal.

The serial data signal generation circuit ₁₁₁ is connected between one side of the AC power supply line AC and the signal line SL, and is configured to generate data according to the transfer data signal generated by the control circuit 10 and during a positive half cycle period of the AC power supply voltage. It turns electricity on and off and creates a serial data signal using a positive cycle signal of the AC power supply voltage.

The detection circuit 13 ₁ is connected between one side of the AC power supply line AC and the signal line SL, that is, connected in parallel with the serial data signal generation circuit 11 ₁ , and detects the negative half cycle period of the AC power supply voltage. This is to detect a negative half-cycle signal of the AC power supply voltage flowing through the signal line SL, that is, a serial data signal from the device 2, which will be described later.

Furthermore, the control circuit 10 has a function of determining the conveyed data of the device 2 based on the serial data signal detected by the detection circuit 13 ₁ .

Next, the device 2 is provided with a control circuit 12, a second serial data signal generation circuit 11 ₂ , and a second detection circuit 13 ₂ .

The control circuit 12 has a second transfer data signal generating means, which generates a transfer data signal corresponding to the transfer data and in which one bit is synchronized with one cycle of the AC power supply voltage.

The serial data signal generation circuit ₁₁₂ is connected between the AC power supply line AC and the other signal line SL, and is configured to generate signals in accordance with the transfer data signal generated by the control circuit 12 and during a negative half cycle period of the AC power supply voltage. It turns electricity on and off and creates a serial data signal using a negative half-cycle signal of the AC power supply voltage.

The detection circuit 13 ₂ is connected between the other AC power supply line AC and the signal line SL, that is, in parallel with the serial data signal generation circuit 11 ₂ , and is connected during the positive half cycle period of the AC power supply voltage. , the positive half-cycle signal of the AC power supply voltage flowing through the signal line SL, that is, the serial data signal from the steam equipment 1 is detected.

Furthermore, the control circuit 12 has a function of determining the transfer data of the device 1 based on the serial data signal detected by the detection circuit 13 ₂ .

Here, the serial data signal generation circuit 11 ₁ ,
11 ₂ and the detection circuits 13 ₁ and 13 ₃ will be described in detail.

First, serial data signal generation circuit 1 of device 1
1 ₁ is a diode D ₁₁ to one L ₁ of the power line AC
The cathode of the diode _D11 is connected to the signal line SL via the switch _SW1 and the resistor _R11 . The switch SW ₁ is turned on and off in response to the transfer data signal b ₁ generated by the control circuit 10 and in synchronization with one cycle of the AC power supply voltage a.

Therefore, when the switch _SW1 is turned on, a positive half-cycle signal appears on the signal line SL as the serial data signal _c1 , and when the switch _SW1 is turned off, no signal is generated on the signal line SL.

The serial data signal generation circuit 11 ₂ of the device 2 is
Connect the cathode of the diode D ₁₂ to the other L ₂ of the power supply line AC, and connect the anode of the diode D ₁₂ to the signal line through the switch SW ₂ and the resistor R ₁₂ .
Connected to SL. The switch SW ₂ is turned on in response to the transfer data signal b ₂ created by the control circuit 12 and in synchronization with one cycle of the AC power supply voltage a.
Turns off to work.

Therefore, when the switch _SW2 is turned on, a negative half-cycle signal appears on the signal line SL as the serial data signal _c2 , and when the switch _SW2 is turned off, no signal is generated on the signal line SL.

Note that it is appropriate to actually use a photocoupler, a photothyristor, or the like as the switches SW ₁ and SW ₂ .

Detection circuit 13 ₁ of device 1 is AC power line AC
The anode of a light emitting diode on the input side of the photocoupler PC 1 is connected to one side L ₁ of the photocoupler PC ₁ via a resistor R ₁₃ , and the cathode of the light emitting diode is connected to the signal line SL. Furthermore, the collector of the phototransistor on the secondary side of photocoupler PC ₁ is connected to a DC power supply.
It is connected to the positive terminal of Vdd, and the emitter of the phototransistor is grounded via resistor _R31 . Then, the voltage generated across the resistor _R31 is supplied to the control circuit 10 as a transfer data detection signal _d1 .

Therefore, the control circuit 10 includes a signal line.
A high-level transfer data detection signal _d1 is input only when a negative half-cycle signal of the AC power supply voltage, that is, a serial data signal _c2 , flows through the SL.

The detection circuit 13 ₂ of the device 2 is an AC power line AC
The anode of the light emitting diode on the input side of the photocoupler PC ₂ is connected to the other end L ₂ of the photocoupler PC 2 via a resistor R ₁₄ , and is connected to the cathode signal line SL of the light emitting diode. Furthermore, the collector of the phototransistor on the secondary side of photocoupler PC ₂ is connected to the DC power supply Vdd.
The emitter of the phototransistor is connected to the positive terminal of the phototransistor and grounded via a resistor _R32 . Then, the voltage generated across resistor _R32 is transferred to the data detection signal.
It is supplied to the control circuit 12 as _d2 .

Therefore, the control circuit 12 includes a signal line.
A high-level transfer data detection signal _d2 is input only when a positive half-cycle signal of the AC power supply voltage a, that is, a serial data signal _c1 , flows through SL.

The operation of this embodiment having the above configuration will be explained.

First, data transfer from device 1 to device 2 will be explained with reference to FIG. 4.

In the device 1, the control circuit 10 creates a transfer data signal _b1 corresponding to the transfer data, for example, "10110011101" and in which one bit is synchronized with one cycle of the AC power supply voltage a. Then, when the transfer data signal _b1 is at the logic "1" level, the switch _SW1 of the serial data signal generation circuit ₁₁₁ is turned on. Further, when the transfer data signal _b1 is at the logic "0" level, the switch _SW1 of the serial data signal generation circuit ₁₁₁ is turned off.

In this way, a serial data signal _c1 is created by the positive half-cycle signal of the AC power supply voltage a, and it flows through the signal line SL.

In the device 2, when the serial data signal _c1 flows through the signal line SL, the light emitting diode of the photocoupler _PC2 in the detection circuit ₁₃₂ emits light, and the phototransistor of the photocoupler _PC2 is turned on.

In this way, the serial data signal _c1 is transmitted to the detection circuit 1.
3 ₂ , and the transfer data detection signal d ₂ corresponding to the serial data signal c ₁ is taken into the control circuit 12 .

The control circuit 12 receives the captured transfer data detection signal.
Determine the transfer data "10110011101" from _d2 .

Next, data transfer from device 2 to device 1 will be explained with reference to FIG. 5.

In the device 2, the control circuit 12 creates a transfer data signal _b2 corresponding to the transfer data, for example, "10100111001" and in which one bit is synchronized with one cycle of the AC power supply voltage a. Then, when the transfer data signal _b2 is at the logic "1" level, the switch _SW2 of the serial data signal generation circuit ₁₁₂ is turned on. Further, when the transfer data signal _b2 is at the logic "0" level, the switch _SW2 of the serial data signal generation circuit ₁₁₂ is turned off.

In this way, the serial data signal _C2 is created by the negative half-cycle signal of the AC power supply voltage a, and it flows through the signal line SL.

In the device 1, when the serial data signal _c2 flows through the signal line SL, the light emitting diode of the photocoupler _PC1 in the detection circuit ₁₃₁ emits light, and the phototransistor of the photocoupler _PC1 is turned on.

In this way, the serial data signal c ₂ is transmitted to the detection circuit 1
3 ₁ , and the transfer data detection signal d ₁ corresponding to the serial data signal ₂ is taken into the control circuit 10 .

The control circuit 10 receives the captured transfer data detection signal.
Determine transfer data “10100111001” from d ₁ .

In this way, in one cycle of the AC power supply voltage a, the positive half cycle signal is used as the serial data signal _c1 from device 1 to device 2, and the negative half cycle signal is used as the serial data signal c1 from device 2 to device 1. By using it as the signal _c2 , bidirectional data transfer between the devices 1 and 2 is possible.

Therefore, it is possible to transmit not only commands from one side of the device to the other side of the device, but also abnormalities and requests of the other side of the device to the one side of the device.

In particular, since only a single signal line SL is provided, there is no _need to worry about incorrect wiring _.
1 , 13 ₂ are circuits that handle AC power supply voltage, so
Even if the wiring is incorrect, no damage will occur. Moreover, the serial data signal generation circuit 11 ₁ ,
11 ₂ and the detection circuits 13 ₁ and 13 ₂ have a simple configuration that only generates and detects a half-cycle signal of the AC power supply voltage, and are inexpensive.

[Effects of the Invention] As described above, in this invention, in two devices connected by an AC power line, one signal line provided between each device and one signal line provided on one side of each device for transmission. Transfer data signal generating means for generating a transfer data signal having a level corresponding to the data and in which one bit is synchronized with one cycle of the AC power supply voltage; A serial data signal generating means is connected between the terminals and the serial data signal generating means for turning on and off the current in accordance with the transfer data signal to generate a serial data signal depending on the presence or absence of the half-cycle signal of the AC power supply voltage, and the signal line on the other side of each device. and the other side of the AC power supply line and detecting the serial data signal, the device 1 and 2 can be connected to each other using a single signal line and with a simple circuit configuration. It is possible to provide a serial data transfer device that enables signal transfer.

[Brief explanation of the drawing]

Figures 1 and 2 are block diagrams of a conventional serial data transfer device, Figure 3 is a block diagram of an embodiment of the present invention, and Figures 4 and 5 are signal waveforms of various parts in the same embodiment. It is a diagram. 1, 2...Equipment, AC...AC power line, SL
... Signal line, 10, 12 ... Control circuit, 11
₁ ...First serial data signal generation circuit, 11 ₂
...Second serial data signal generation circuit, 13 ₁
...first detection circuit, 13 ₂ ...second detection circuit.

Claims (1)

[Claims] 1 In two devices connected by an AC power line, one signal line provided between each of the devices and one bit provided on one side of each device corresponds to the transfer data, and one bit is connected to the AC power source. a first transfer data signal generating means for generating a transfer data signal synchronized with one cycle of voltage; a first serial data signal generating means that turns on and off during a positive half cycle period of the AC power supply voltage in response to the positive half cycle period of the AC power supply voltage to create a serial data signal according to the positive half cycle signal of the AC power supply voltage; a first detection means connected between one of the power supply lines and the signal line for detecting a half-cycle signal flowing through the signal line during a negative half-cycle period of the AC power supply voltage; and a first detection means provided on the other side of each of the devices. a second transfer data signal that corresponds to the received transfer data and in which one bit is synchronized with one cycle of the AC power supply voltage;
a transfer data signal generating means connected between the other side of the AC power supply line and the signal line on the other side of each of the devices and turned on and off during a negative half cycle period of the AC power supply voltage according to the transfer data signal; and a second serial data signal generating means for generating a serial data signal based on a negative half-cycle signal of the AC power supply voltage; A serial data transfer device comprising: second detection means for detecting a half-cycle signal flowing through the signal line during a positive half-cycle period of a power supply voltage.