JPH07219631A - Control unit for equipment - Google Patents

Abstract

PURPOSE:To easily detect abnormality such as the disconnection of a transmission line for serial communication between a main control unit and an auxiliary control unit. CONSTITUTION:A dummy bit signal is inputted to the parallel signal input part 22X of the 2nd parallel-serial converting means 22 of the auxiliary control unit 20 to which no external signal is inputted and the main control unit 10 decides whether or not the dummy bit signal is present at a specific position in the received signal from the auxiliary control unit 20, thereby performing abnormality processing unless the presence is decided.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a main controller equipped with a microcomputer (hereinafter referred to as "microcomputer") and an auxiliary controller equipped with controlled elements such as relays whose energization is controlled by a control signal from the main controller. The present invention relates to a control device for equipment such as a boiler.

[0002]

2. Description of the Related Art A conventional control device of this type will be described by taking a boiler as an example. For example, in a control device for a small-sized and simple-class boiler (including a hot water boiler), boiler components (water supply pump, fuel pump, blower, solenoid valve in each pipe, etc.) are responded to by control signals from a microcomputer. It is controlled via a relay. The operating status of the above-mentioned components is detected by various sensors such as a pressure switch, a seismic sensor, an overcurrent detector, etc., and is input to the microcomputer.

Microcomputers generally operate at a very weak voltage and have a problem that they are vulnerable to high-voltage electricity and noise. Relays such as the one above generally open and close high voltage contacts, and also the above pressure switch, seismic
Since contact type sensors such as overcurrent detectors detect the state by opening and closing high voltage contacts, if such a relay or sensor exists near the microcomputer, the microcomputer will malfunction due to noise during opening and closing. There is a lot of fear.

The operating temperature range of the microcomputer and its peripheral semiconductor elements is narrower than that of the relays and sensors as described above, and the vicinity of an operation panel or a display device for a human to operate the boiler, that is, a human. It is usually installed in an environment where it can be operated by. On the other hand, the above-mentioned relays and sensors can be installed even under environmental conditions such as high temperature and high pressure.

In consideration of these points, the main controller including the microcomputer and the auxiliary controller including the relay and the like are separately mounted on the microcomputer board and the relay board, respectively. Is placed in a place where the environmental conditions are good, and both substrates are placed apart from each other. Such a conventional specific configuration will be described with reference to FIG.

That is, the conventional control device includes a main control device 1 including a microcomputer 2 and its peripheral semiconductor elements (not shown),
The auxiliary control device 3 controls the energization of the equipment to be controlled, etc., and is configured on separate substrates. The auxiliary control device 3 also serves as a repeater for inputting an output from a sensor (not shown) to the main control device 1. .. and the main control device 1 of the auxiliary control device 3
The transmission and reception of signals to and from each other and transmission lines 5 and 5 corresponding to the relays 4, 4, ...
, And the sensor output, the connection with the main controller 1 and the transmission / reception of signals between them are individually performed by the transmission lines 6, 6 ... Corresponding to each sensor. It should be noted that a part of the signal from the sensor is performed through the interface circuit unit 7 provided in the auxiliary control device 3, and this interface circuit unit 7 sends a high voltage signal from the sensor to an electronic device such as a microcomputer. It has a voltage conversion function for converting a low voltage signal to be handled (for example, 200 V to 5 V).

[0007]

However, if the number of devices to be controlled or the number of sensors is increased for more efficient operation in the above control device, the increase will be dealt with. Therefore, the number of relays increases, and at the same time, the number of transmission wirings for each relay and each sensor also increases. Therefore, there arises a problem that the cost for the wiring and the cost for the noise measure increase. In particular, when high-speed signal transmission is not required, such as when driving the above-mentioned relay or incandescent lamp, it is excessive quality to route the wiring corresponding to each output as described above.

In order to solve such a problem, in the main control device, the parallel transmission signal output from the microcomputer is converted into a serial transmission signal and is output to the first transmission line to be transmitted to the auxiliary control device. The received signal is converted into a parallel signal and output to the controlled element. The auxiliary control device converts the input parallel external signal into a serial transmission signal and outputs it to the second transmission line. The main control device converts the serial reception signal into a parallel signal. It is conceivable that the number of transmission lines can be reduced and the number of sensors and relays can be increased by configuring the signal to be converted into a signal and input to the microcomputer.

However, in such a solution, although there is an advantage that the number of transmission lines can be reduced, auxiliary control of external input signals such as all sensor signals is caused only by disconnection or disconnection of the reception transmission line for some reason. Transmission from the device to the main control unit becomes impossible. Then, the specific signal pattern of the external input signal such as the sensor signal input to the auxiliary control device may be the same as the signal pattern in the case where the disconnection of the transmission line occurs. There is a problem that detection cannot be performed easily.

[0010]

The present invention has been made for the purpose of solving the above-mentioned problems.
Of the invention, a microcomputer, a first parallel-serial conversion means for converting a parallel transmission signal output from the microcomputer into a serial transmission signal and outputting the serial transmission signal to the first transmission line, and a serial reception signal from the second transmission line are received in parallel. A main control device including a first serial-parallel conversion means for converting into a signal and outputting to a microcomputer, a controlled element controlled by a signal transmitted from the main control device through the first transmission line, and the first transmission Second serial-parallel conversion means for converting a serial reception signal from the line to a parallel reception signal and outputting the parallel reception signal to the controlled element; and a second serial-parallel conversion means for converting a parallel transmission signal into a serial transmission signal and outputting the serial transmission signal to the second transmission line. The parallel-serial conversion means and the plurality of parallel signal input sections of the second parallel-serial conversion means are connected. In a controller of a device including an auxiliary controller including a plurality of external signal input lines, a dummy signal input unit for inputting a dummy bit signal to the parallel signal input unit to which the external signal of the second parallel-serial conversion unit is not input. And a determination means for determining whether or not the dummy bit signal is present in the received signal from the auxiliary control device, and an abnormality processing means for performing abnormality processing when the presence is not determined by the determination means. According to the invention of claim 2,
The first transmission line and the second transmission line are configured by different signal lines, and the invention of claim 3 is the dummy signal according to claim 1, wherein a dummy bit signal is input to the auxiliary control device at regular intervals. The main control device is provided with determining means for determining the presence / absence of a dummy bit signal for each fixed cycle, and the invention according to claim 4 is a microcomputer and a parallel transmission signal output from the microcomputer. To a serial transmission signal and outputs the same to a first transmission line to a first transmission line, and a first serial-parallel conversion that converts a serial reception signal from the second transmission line into a parallel reception signal and outputs the parallel reception signal to a microcomputer. A main control device including means, a controlled element controlled by a signal transmitted from the main control device through the first transmission line, the first transmission line The converts the serial signal received from the on to the parallel received signal and outputs the to the controlled device 2
Serial-parallel conversion means, second parallel-serial conversion means for converting a parallel transmission signal into a serial transmission signal and outputting the serial transmission signal to the second transmission line, and a plurality of parallel signal input sections of the second parallel-serial conversion means A controller for an apparatus including an auxiliary controller including a plurality of external signal input lines, and a first dummy signal input unit for including a dummy bit signal in a parallel transmission signal output from the microcomputer; and the auxiliary controller. Second
Second dummy signal input means for inputting the dummy bit signal in the serial received signal received by the serial-parallel conversion means to the second serial-parallel conversion means, and included in the received signal from the second parallel-serial conversion means. It is characterized by further comprising a judging means for judging the presence / absence of the dummy bit signal to be generated, and an abnormality processing means for carrying out an abnormality processing when the existence thereof is not judged by the judging means.

[0011]

According to the means of claim 1, the dummy bit signal is inputted to the signal input portion of the second parallel-serial conversion means to which the external signal is not inputted and is transmitted from the auxiliary control device to the main control device. The dummy bit signal is included in the signal, and the main control unit side determines whether the received signal contains the dummy bit signal by the determination means. When it is determined that the bit signal is not included, the abnormality processing means performs the abnormality processing. According to the means of claim 2, the transmission of the signal from the main control device to the auxiliary control device is performed through the first transmission line,
The reception of a signal from the auxiliary control device to the main control device is the first
The transmission is performed through a second transmission line that is separate from the transmission line, and a signal is transmitted and received between the main control device and the auxiliary control device without requiring a transmission control means such as a microcomputer on the auxiliary control device side. According to the means of claim 3, the dummy bit signal is transmitted from the auxiliary control device to the main control device at regular intervals, and the main control device determines the presence or absence of the dummy bit signal at regular intervals. According to the means of claim 4, in the main control device, the dummy bit signal is included in the parallel transmission signal output from the microcomputer by the first dummy signal input means, and the parallel transmission signal is converted into the serial signal to be the auxiliary control device. The dummy bit signal in the serial reception signal received by the second serial-parallel conversion means in the auxiliary control device is input to the second serial-parallel conversion means.
The parallel signal transmitted to the main control device is transmitted from the second parallel-serial conversion means to the main control device in a state in which the data includes the dummy bit signal. The main control unit receives the serial signal through the second transmission line, determines the presence or absence of the dummy bit signal included in the received signal by the determination unit, and performs an abnormal process when the presence is not determined by the determination unit.

[0012]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The construction and operation of a preferred embodiment of the boiler control apparatus according to the present invention will be described below with reference to FIGS. 1 is a schematic configuration diagram of an electrical main part of the embodiment, and FIG. 2 is a diagram showing a main part of a processing procedure of a microcomputer of the main control device.

The control device according to this embodiment includes a main control device 10 for inputting an external signal such as a sensor and outputting a control signal for a control target device including a boiler component device and a boiler peripheral device (water softener, etc.); Target device is main controller 1
The main controller 10 is controlled directly or indirectly by a control signal from 0 and relays an external input signal from a sensor or the like.
And an auxiliary control device 20 having a function of sending to the.
Incidentally, the equipment to be controlled usually corresponds to a water supply pump, a fuel pump, a blower and solenoid valves in each pipe in a steam boiler, and an electric heater in place of the fuel pump and the blower in an electric boiler. To do.

The main controller 10 includes a microcomputer 11 and peripheral semiconductor elements (not shown) such as a memory, a first parallel-serial conversion mechanism 12, a first serial-parallel conversion mechanism 13, data transmission terminals 14a, 14b, 14
c, 14d, and the sensor terminal group 15 are provided on one substrate, and the auxiliary control device 20 includes the second serial-parallel conversion mechanism 21 and the second parallel-serial conversion mechanism 2.
2, data transmission terminals 23a, 23b, 23c, 23
d, controlled elements 24, 24, ..., Which are composed of relays, and external signal input terminal groups 25, ... For sensors are provided on a board different from the main controller 10. Then, the data transmission terminals on the main control device 10 side and the data transmission terminals on the auxiliary control device 20 side correspond to the corresponding terminals by transmitting the first transmission line 26a for transmission, the third transmission line 26b, and the fourth transmission line 26b. A signal between the main control device 10 and the auxiliary control device 20, that is, a control signal for changing or maintaining the operation of each controlled device and the microcomputer 11 are connected by the transmission line 26c and the second reception transmission line 26d. Boiler operation status output signals from the respective sensors are transmitted and received through these four transmission lines. That is, the serial transmission data from the main controller 10 to the auxiliary controller 20 is transmitted through the first transmission line 26a, and the clock for synchronizing each data of the serial data from the main controller 10 to the auxiliary controller 20 is the third transmission line. 26b, the data start and end timing signals are transmitted through the fourth transmission line 26c, and the serial transmission data transmitted from the auxiliary controller 20 to the main controller 10 is transmitted through the second transmission line 26d.
If asynchronous communication in which clock timing is synchronized is adopted on the controlled element side, the clock signal line 26
b and the timing control line 26c can be omitted.

The microcomputer 11 of the main control unit 10 judges the operation status of the boiler based on external input signals from each sensor described later, and outputs a signal for changing or maintaining the operation status of each controlled equipment. It is what is output. Then, the microcomputer 11 detects whether the data signal received from the auxiliary control device 20 includes a dummy bit signal, which will be described later, according to a processing procedure stored in advance in a storage device (not shown), and detects an abnormality such as disconnection or disconnection of the transmission line. It performs various functions such as an abnormality processing function of notifying it. An example of the main part of the processing procedure is shown in FIG.

The first parallel-serial conversion mechanism 12
In addition, the first serial-parallel conversion mechanism 13 includes the microcomputer 11 and the data transmission terminals 14a, 14b, 14
It is connected between c and 14d, and is connected to the microcomputer 11 and the first
Between the parallel-serial conversion mechanism 12, the microcomputer 1
.. are connected by the number of data lines 16, 16 ... Corresponding to the number of processing unit bits of 1, for example, 8 bits, and the processing unit bit number of the microcomputer 11 is similarly set between the microcomputer 11 and the serial-parallel conversion mechanism 13. Connection is made by a corresponding number of data lines 17, 17, ....

The first parallel-serial conversion mechanism 12
Is a plurality of data lines 16, 1 from the microcomputer 11.
The signals transmitted in parallel by 6 ... Are converted into a series (8 bits in this case) of serial data (serial data) signals and output to the auxiliary controller 20. Here, in the data signal output from the parallel-serial conversion mechanism 12, each bit of a series (one or all) of serial data strings corresponds to an operation instruction for each controlled element. Specifically, for example, eight controlled elements 24
"a", 24b, 24c, 24d ...
When it is desired to perform control such that "OFF", "ON", "ON", ..., The 8-bit parallel control signal "1011 ..." Is sent from the microcomputer 11 to the eight data lines 16a, 16
b, 16c, 16d ... That is, the transmission signal "1" by the data line 16a becomes the control signal of the controlled element 24a, the transmission signal "0" by the data line 16b becomes the control signal of the controlled element 24b, and the transmission signal "1" by the data line 16c becomes It becomes the control signal for the controlled element 24c, and the transmission signal "1" by the data line 16d becomes the control signal for the controlled element 24d. Therefore, the controlled element 24a is turned on by the signal of the first bit of the serial data, and the controlled element 2a is turned on by the signal of the second bit.
Each bit of the serial data string of a set of 8 bits corresponds to an operation instruction for each controlled element such that 4b is turned on. Note that, for example, when 18 controlled elements are connected to the second serial-parallel conversion mechanism 21 and it is desired to control them, the microcomputer 11 outputs a set of 8-bit serial data signals twice. . Of course, if the microcomputer 11 uses 16 bits as a processing unit, it only needs to be processed once. In this case, the conversion mechanism 12 uses a 16-bit compatible unit.

Further, the first serial-parallel conversion mechanism 13 outputs a set of time-series data (serial data) from the auxiliary control device 20 for each predetermined number of bits (8 bits in this case). By receiving the signals in a divided manner, the signals are converted into signals transmitted in parallel by the plurality of data lines 17, 17 ... Then, the first serial-parallel conversion mechanism 13
In the data signal output from, each bit of each data line 17, 17 ... Corresponds to the output of each sensor, as described later. The second transmission line 26d is connected to the main controller 10
Since the portion between the terminal 14d of the first and the conversion mechanism 13 is pulled down and maintained at the low level, when the receiving data line 26d is disconnected, the first serial-parallel conversion mechanism 1
The received data of No. 3 are all "0", so that the input signals of the microcomputer 11 are all "0". As the first parallel-serial conversion mechanism 12 and the first serial-parallel conversion mechanism 13, a single shift register or a shift register built in the microcomputer 11 is used.

The second serial-parallel conversion mechanism 21 of the auxiliary control device 20 converts a received data signal (serial data) from the main control device 10 into a parallel control signal for each controlled element 24. To do. Specifically, for example, 8
The bit serial signal is converted into an 8-bit parallel control signal “1011 ...”, and eight control output lines 29a, 29b, 29c, 29d ...
8 controlled elements 24a, 24b, 24c, 24
It is transmitted to d ...
N ”,“ ON ”...

Sensor terminal group 2 of the auxiliary controller 20
5 is for inputting a signal from each sensor for detecting the operating condition of the boiler, and the sensor terminal group 2
Examples of sensors connected to 5 ... are contact-type sensors that open and close high-voltage contacts such as the steam pressure switch, seismic sensor, and overcurrent detector described above. As in the conventional example shown in FIG. 2, some of the signals from these sensors pass through the interface circuit section 7 provided in the auxiliary control device 20, and the rest do not pass through the interface circuit section 7,
It is input to the parallel-serial conversion mechanism 22. The parallel-serial conversion mechanism 22 includes a sensor terminal group 25.
Converts external signals input from each sensor connected to ... into serial signals. Specifically, for example, a signal input to the input unit 22N of the conversion mechanism 22 through the number of external signal input lines 27, 27, ... Corresponding to 8 bits is converted into an 8-bit serial data signal, and the second transmission line 26
Output to the main controller 10 through d. And
Among the input sections 22N, there is an input section 22X to which the external signal input line 27 is not connected, and this input section 22X is used as a dummy bit input section. That is, this input unit 2
By inputting a high level signal to 2X, the dummy bit signal "1" is input.

Therefore, each bit data of the set of serial data strings output from the second parallel-serial conversion mechanism 22 is input through the signal lines 27, 27, ..., "0" or "1" for each sensor. And the dummy bit “1”. For example, 7 types of external signals and 1
If the bit is a dummy bit, the conversion mechanism 1
The serial data string output from 2 is "1110 ...
The signal becomes an 8-bit signal such as "1", and the last bit is a dummy bit, for example. The position of the dummy bit is arbitrarily set by hardware depending on which input unit 22N is used as the dummy bit input unit 22X. The second serial-parallel conversion mechanism 21 and the second parallel-serial conversion mechanism 22 described above.
As described above, a single shift register is used as described above.

The controlled elements 24, 24 ...
As described above, it is a means for operating the controlled equipment such as the water supply pump, the fuel pump, the blower, and the solenoid valve in each pipe by a weak low-voltage signal, especially a relay or a driving means instead of the relay. In addition, it is directly driven by the output voltage (for example, 5V) of the second serial-parallel conversion mechanism 21 in the lamps for displaying, warning, illuminating, etc., such as LEDs and incandescent lamps, and in the photo coupler and the like. Controllable devices that can be directly controlled are also included in the controlled element according to the present invention. Further, the auxiliary control device 20 is provided with a power supply line 32, and this line has a contact 30 which is turned on and off by the microcomputer 11.

Further, the sensor terminal group 15 on the main controller 10 side mainly includes a temperature sensor for detecting the temperature of the boiler can body, a flame sensor for detecting the flame condition of the burner,
Connect a sensor that measures and outputs a continuous value, such as a pressure sensor that detects the pressure inside the boiler can. Of course, the contact type sensor as described above may be connected to the sensor terminal group 15 on the main controller 10 side.

Next, the operation of the above embodiment will be described with reference to FIGS. The state signal "1" or "0" signal from the sensor is input to the input unit 22N of the second parallel-serial conversion mechanism 22 and the dummy bit signal "1" is input via the external signal input lines 27. It is input to the section 22X. As a result, the parallel data signal input to the conversion mechanism 22 becomes an 8-bit data signal including a 7-bit external signal such as "1110 ... 1" and a 1-bit dummy bit. In this case, the last bit is "1"
Is a dummy bit. This parallel signal is converted by the conversion mechanism 2
8 bit serial data signal "1" by 2
110 "... 1" is output to the second transmission line 26d, is received by the first parallel-serial conversion mechanism 13 of the main controller 10, and is converted into an 8-bit parallel data signal again, and the data lines 17, 17 ... Is received by the microcomputer 11 via.

In processing step S1 (hereinafter, SN means processing step SN), it is determined whether or not there is received data in the first serial-parallel conversion mechanism 13 (whether it is in the middle of reception). If NO, stay in S1. In the case of YES, the process proceeds to S2 and it is determined whether or not a dummy bit signal is included in a predetermined bit position in the received data. Since the position of the dummy bit is known depending on where the dummy bit signal input section 22X is set, it is programmed in advance so that it can be determined by the microcomputer 11. If YES is determined in S2, the process proceeds to S4, the received data is processed according to a predetermined processing procedure, and the process returns. When NO is determined a predetermined number of times (one or more times) in S2, the process proceeds to S3 to notify an annunciator such as a display (not shown) of the abnormality of the transmission line,
An abnormal process of opening the contact 30 and stopping the boiler device is performed. Incidentally, it is desirable that the notification of the abnormality be made by simultaneously displaying an abnormal stop of the boiler device and displaying "transmission line abnormality" indicating the cause thereof.

The second transmission line 26d is disconnected or disconnected (note that
In the case of disconnection, the transmission lines are usually bundled or integrated at least in the terminal part (connector part),
If all the transmission lines are disconnected), conventionally, an 8-bit signal of "0000 ... 0" is input to the microcomputer, and the external input signal (status signal) from the sensor is received when all are "0". It could not be identified as a signal "0000 ... 0". However, according to the present embodiment, the dummy bit signal "1" is included in the predetermined bit position of the reception signal of the microcomputer 11 when the transmission line 26d is not disconnected, so that the processing of S2 and S3 can be performed. It is possible to distinguish between normal and abnormal. Then, in the case of abnormality, necessary abnormality processing can be performed, and the control device can be provided with a fail-safe function. As described above, in the first embodiment, there is an effect that a check bit (dummy bit) is input using the empty input section of the second parallel-serial conversion mechanism 22 and abnormality of the transmission line can be easily performed.

Next, a second embodiment of the present invention will be described with reference to FIGS. The difference from the first embodiment of FIGS. 1 and 2 is that in the first embodiment, dummy bits “1” are continuously input to the dummy bit input unit 22X of the second parallel-serial conversion means 22. While this is configured to be detected by the microcomputer 11, in the present embodiment, "1" and "0" are alternately input to the dummy bit signal input section 22X, or "1" is input at regular intervals. Some are configured to enter. Specifically, as shown in FIG. 3, an oscillator 28 is connected to the dummy bit input section 22X, and the microcomputer 1
The processing procedure of No. 1 is characterized in that in the determination of S12, a determination step of dummy bit "1" is provided at regular intervals. In addition, S11 is S1 and S13 is S3.
Further, S14 corresponds to S4, respectively, and since the processing content is the same, description thereof will be omitted. According to the second embodiment, in addition to the effect of the second embodiment, the effect that the check bit signals of "0" and "1" can be input and the abnormality of the transmission line can be surely detected by the two kinds of check bits. There is.

Next, a third embodiment of the present invention will be described with reference to FIGS. The feature of the present embodiment is that, in the main control unit 10, a bit which does not carry a control signal for the controlled element 24 among the output signal from the microcomputer 11, for example, an 8-bit signal is preset and the bit position is set. The dummy bit signal is input to the CPU 11 by the processing of the microcomputer 11 (first dummy bit signal input means), and the second parallel-serial conversion mechanism 2 is provided on the auxiliary control device 20 side.
By connecting the dummy bit signal input unit 22X of No. 2 and the predetermined output unit 21S of the second serial-parallel conversion mechanism 21 corresponding to the output control lines 29 ... Which are not used for controlling the controlled element by the wiring 30. The dummy bit signal input by the main controller 10 is output from the output unit 21S and input to the input unit 22X. The main part of the processing procedure of the microcomputer 11 of this embodiment is shown in FIG. 6, and the operation of this embodiment will be described with reference to FIG. S
At 21, the microcomputer 11 adds the dummy bit signal “1” to the determined position of the 8-bit transmission data, for example, and transmits it to the auxiliary control device 20. In the auxiliary control device 20, the received 8-bit serial signal is converted into a parallel signal by the second serial-parallel conversion mechanism 21 and output from the control output lines 29 .... Although 7 bits out of 8 bits are control signals of the controlled element 24, the signal from the output section 21S is input to the dummy bit signal input section 22X of the second parallel-serial conversion mechanism 22. The 1-bit dummy signal thus input is converted into a serial signal together with the 7-bit signal input from the remaining input unit 22N and transmitted to main controller 10.

In S22, it is determined whether or not the data is received (acquired) by the conversion mechanism 13. N at S22
In the case of O, it remains at S22. If YES, the process proceeds to S23, and it is determined whether or not a dummy bit exists at a predetermined position. It should be noted that the microcomputer 11 transmits the 8-bit signal from the conversion mechanism 12 and immediately thereafter, the conversion mechanism 2 of the auxiliary control device 20.
Since the 8-bit signal is transferred from 2 to the conversion mechanism 13, the determination in S23 is possible. S2
If NO is determined in 3, the abnormal process similar to S3 is performed in S25, and the process ends. If YES is determined in S23, the process proceeds to S24 and the normal process similar to S4 is performed.
Go to 6. In S26, the microcomputer 11 adds the dummy bit signal "0" to the determined position of the transmission data and transmits it to the auxiliary control device 20. In S27, the conversion mechanism 1
It is determined in 3 whether the data is received. If NO in S27, the process remains in S27. If YES, the process proceeds to S28, and it is determined whether or not a dummy bit exists at a predetermined position.
If NO is determined in S28, the same abnormal process as in S3 is performed in S29, and the process ends. If YES is determined in S28, the process proceeds to S30 and normal processing similar to S4 is performed.

As described above, in the third embodiment, the following effects can be obtained by sending two kinds of dummy bit signals.
That is, the transmission line 26d is connected to the terminal 14d of the main controller 10.
In this embodiment in which the portion between the conversion mechanism 13 and the conversion mechanism 13 is pulled down and maintained at a low level, when the transmission line 26d is disconnected, all the reception signals of the microcomputer 11 become "0", but the portion is reversed. In the device which is pulled up to and maintained at the high level, when the transmission line 26d is disconnected, on the contrary, all the reception signals of the microcomputer 11 become "1". Therefore,
By sending "1" and "0", there is an effect that any device can be supported. Further, there is also an effect that erroneous judgment due to a signal transmission error can be prevented.

The present invention is not limited to the above-described embodiments, but includes, for example, the following modified embodiments (1) to (5).

(1) Equipment other than a boiler, such as a soft water producing apparatus incorporating the control device according to any one of claims 1 to 4. Also in this embodiment, the same effect as the boiler can be expected.

(2) A control device in which the first transmission line 26a and the second transmission line 26d are shared by one transmission line. In this case, specifically, a microcomputer (not shown) is also provided on the side of the auxiliary control device 20, and half-duplex transmission is performed between this microcomputer and the microcomputer 11 of the main control device 10. According to this embodiment, the number of transmission lines can be further reduced.

(3) First parallel-serial conversion mechanism 12
And an example in which the first serial-parallel conversion mechanism 13 is shared by one conversion mechanism. Specifically, a shift register built in the microcomputer 11 is used. According to this embodiment, the first parallel-serial conversion mechanism 12 and the first serial-parallel conversion mechanism 13 can be shared by a built-in register in one microcomputer, and the main controller can be downsized and the cost can be reduced.

(4) An embodiment in which "0" is input as a dummy bit signal in the embodiment of FIG. In this embodiment, the transmission line 26d is connected to the terminal 14 of the main controller 10.
It is applied to a portion between d and the conversion mechanism 13 that is pulled up and maintained at a high level. In this case, the external signal can be distinguished from the received signal pattern of all "1".

(5) In FIG. 6 of the third embodiment, a series of processing steps S21 to S25 and processing steps S26 to S25.
230 An example in which only one of a series of processes is performed. In the case of performing only the series of processing steps S21 to S25, the transmission line 26d is connected to the terminal 14 of the main controller 10.
It is suitable for a control device that pulls down the portion between d and the conversion mechanism 13 to a low level, and processing steps S26 to S3.
The one performing only a series of processes of 0 is suitable for a control device in which the transmission line 26d is pulled up to a high level at a portion between the terminal 14d of the main control device 10 and the conversion mechanism 13.

[0037]

As described above, according to the control device of the present invention, all the external signals of a plurality of sensors and the like are "0" or "1" and all the received signals of the microcomputer are "0" or "1". It is possible to easily discriminate between the case where the transmission line connecting the main control unit and the auxiliary control unit is disconnected or the transmission line is disconnected and all the reception signals of the microcomputer of the microcomputer become “0” or “1”. It is possible to perform abnormality determination and notification due to disconnection or disconnection. Therefore, it is possible to prevent a malfunction of the device due to an erroneous external input signal, and it is possible to provide a highly safe control device.

[Brief description of drawings]

FIG. 1 is an electrical schematic configuration diagram showing an embodiment of the present invention.

FIG. 2 is a flowchart showing an example of a processing procedure of a microcomputer of the same embodiment.

FIG. 3 is an electrical schematic configuration diagram showing another embodiment of the present invention.

FIG. 4 is a flowchart showing an example of a processing procedure of the microcomputer of the embodiment.

FIG. 5 is an electrical schematic configuration diagram showing another embodiment of the present invention.

FIG. 6 is a flowchart showing an example of a processing procedure of a microcomputer according to another embodiment of the present invention.

FIG. 7 is an electrical schematic configuration diagram of a conventional example.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 main control device 11 microcomputer 12 1st parallel-serial conversion mechanism 13 1st serial-parallel conversion mechanism 20 auxiliary control device 21 2nd serial-parallel conversion mechanism 22 2nd parallel-serial conversion mechanism 22X dummy bit input part 23 controlled Element 26a First data transmission wiring 26d Second data transmission wiring

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁶ Identification code Internal reference number FI Technical display location F22B 35/18 7526-3L G05B 9/02 L 15/02 17/02 7531-3H G06F 11/00 310 C 13/00 301 E 15/78 510 K H04Q 9/00 311 L

Claims (4)

[Claims] 1. A microcomputer, a first parallel-serial conversion means for converting a parallel transmission signal output from the microcomputer into a serial transmission signal and outputting the serial transmission signal to the first transmission line, and a serial reception signal from the second transmission line. To a parallel reception signal and output to a microcomputer, the main control device including a first serial-parallel conversion means, and a controlled element controlled by a signal transmitted from the main control device through the first transmission line, Second serial-parallel conversion means for converting a serial reception signal from the first transmission line into a parallel reception signal and outputting the parallel reception signal to the controlled element, and a second transmission line for converting the parallel transmission signal into a serial transmission signal. Second parallel-serial conversion means for outputting to and the second parallel-serial conversion In a controller of a device comprising an auxiliary controller including a plurality of external signal input lines connected to a plurality of parallel signal input sections of the means, a signal input section to which an external signal of the second parallel-serial conversion mechanism is not input is provided. Dummy signal input means for inputting a dummy bit signal, judging means for judging whether or not the dummy bit signal is present in the received signal from the auxiliary control device, and abnormal processing when the existence is not judged by this judging means An abnormality control means for performing the above. 2. The apparatus control device according to claim 1, wherein the first transmission line and the second transmission line are formed by different signal lines. 3. The dummy signal input means for inputting a dummy bit signal to the auxiliary control device at every constant cycle according to claim 1, and the determining means for determining the presence or absence of the dummy bit signal at the constant cycle at the main control device. A device control device characterized in that each device is provided. 4. A microcomputer, a first parallel-serial conversion means for converting a parallel transmission signal output from this microcomputer into a serial transmission signal and outputting the serial transmission signal, and a serial reception signal from the second transmission line. To a parallel reception signal and output to a microcomputer, the main control device including a first serial-parallel conversion means, and a controlled element controlled by a signal transmitted from the main control device through the first transmission line, Second serial-parallel conversion means for converting a serial reception signal from the first transmission line into a parallel reception signal and outputting the parallel reception signal to the controlled element, and converting a parallel transmission signal into a serial transmission signal to the second transmission line. Second parallel-serial conversion means for outputting and this second parallel-serial conversion means In a controller of a device including an auxiliary controller including a plurality of external signal input lines connected to a plurality of parallel signal input sections of a stage, a parallel transmission signal output from the microcomputer includes a dummy bit signal. 1 dummy signal input means, and 2nd dummy signal input means for inputting the dummy bit signal in the serial received signal received by the 2nd serial-parallel conversion means of the auxiliary control device to the 2nd serial-parallel conversion means, It is provided with a judging means for judging the presence / absence of a dummy bit signal included in the received signal from the second parallel-serial converting means, and an abnormality processing means for carrying out an abnormal processing when the presence thereof is not judged by the judging means. Characteristic equipment control device.