Communication Systems

Abstract

To provide a communication system capable of reducing the number of microcomputer serial ports at a slave side device.SOLUTION: A slave side device 30 includes a wireless communication module 31 capable of receiving data from a master side device 20 by wireless communication. The slave side devices 30, 40 and 50 respectively include microcomputers 34, 43 and 53 connected to the wireless communication module 31 to be capable of data communication. RS485 drivers 32 and 33 are provided between the wireless communication module 31 and the microcomputer 34 in the slave side device 30, data received by the wireless communication module 31 through a communication line L2 are sent to the microcomputer 34 by serial communication in the slave side device 30. Data received by the wireless communication module 31 are sent to the microcomputers 43 and 53 through serial communication by branching the communication line L2 and connecting to the microcomputers 43 and 53 through RS485 drivers 42 and 52 in the slave side devices 40 and 50.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to communication systems. [Background technology]

[0002] In a communication system, in a one (master) to multiple (slave) configuration, as shown in FIG. 2, communication between a master side device 100 and slave side devices 101, 102, 103 is performed by RS485 communication using communication lines L100, L101, L102, L103 (see, for example, Patent Document 1). Also, as shown in FIG. 3, communication between a master side device 200 and slave side devices 201, 202, 203 is performed by wireless communication using wireless communication modules 201a, 202a, 203a. Furthermore, as shown in FIG. 4, as communication from a master side device 300 to slave side devices 301, 302, 303, a relay device such as a gateway 304 receives data by wireless communication and performs RS485 communication using a communication line L300 (see, for example, Patent Document 2). At this time, a microcomputer 304a in a relay device such as a gateway 304 uses multiple serial ports P300, P301. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2018-78502 A [Patent Document 2] JP 2017-98762 A Summary of the Invention [Problem to be solved by the invention]

[0004] In the case of the wired system in Fig. 2, the longer the cable, the higher the cost of the cable and the wiring imposes installation restrictions. Compared to the wired system in Fig. 2, the wireless system in Fig. 3 can eliminate the need for cables, but wireless communication requires wireless communication modules (including communication means such as antennas) 201a, 202a, and 203a for each of the slave devices 201, 202, and 203. In the case of Fig. 4, a relay device such as a gateway 304 is required separately. Incidentally, if a configuration is adopted in which communication from a master side device 400 to slave side devices 401, 402, 403 is received by one wireless communication module 404 and connected to the microcomputer 402a, 403a of the other slave side devices 402, 403 by RS485 communication using a communication line L400 without using a relay device such as a gateway, as shown in FIG. 5, then the microcomputer 401a of the slave side device 401 connected to the wireless communication module 404 will require a serial port P400 connected to the wireless communication module 404, and a serial port P401 connected to the RS485 driver 401b.

[0005] An object of the present invention is to provide a communication system capable of reducing the number of serial ports of a microcomputer in a slave device. [Means for solving the problem]

[0006] A communication system for solving the above problem is a communication system comprising a master side device and a plurality of slave side devices, one of the plurality of slave side devices comprising a wireless communication module capable of receiving data from the master side device via wireless communication, each of the plurality of slave side devices comprising a microcomputer connected to the wireless communication module so as to be capable of data communication, a pair of transmit / receive serial communication drivers is provided between the wireless communication module and the microcomputer in one of the slave side devices, data received by the wireless communication module through a communication line connecting the pair of transmit / receive serial communication drivers is sent by serial communication to the microcomputer in the one of the slave side devices, and a communication line is branched off from the communication line and connected to a microcomputer in another of the plurality of slave side devices via a serial communication driver, so that data received by the wireless communication module is sent by serial communication to the microcomputer in the other slave side device.

[0007] According to this, by branching off a communication line connecting a pair of transmit / receive serial communication drivers between a wireless communication module and a microcontroller in one slave side device and connecting to a microcontroller in another slave side device via a serial communication driver, it is possible to reduce the number of serial ports of the microcontroller in the slave side device.

[0008] In the communication system, the pair of transmitting and receiving serial communication drivers and the serial communication driver in the other slave device may be RS485 drivers. In this case, the use of RS485 communication makes it possible to improve resistance to noise and to communicate over long distances. Effect of the Invention

[0009] According to the present invention, it is possible to reduce the number of serial ports of the microcomputer in the slave device. [Brief description of the drawings]

[0010] [Figure 1]FIG. 2 is an electrical configuration diagram of a communication system according to an embodiment. [Diagram 2] FIG. 1 is an electrical configuration diagram of a conventional communication system. [Diagram 3] FIG. 1 is an electrical configuration diagram of a conventional communication system. [Figure 4] FIG. 1 is an electrical configuration diagram of a conventional communication system. [Diagram 5] FIG. 1 is an electrical configuration diagram of a communication system for explaining a problem. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0011] DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will now be described with reference to the drawings. In this embodiment, the present invention is applied to a window opening and closing device in an agricultural greenhouse. As shown in Fig. 1, a communication system 10 includes a master device 20 and a plurality of slave devices (30, 40, 50). For ease of explanation, Fig. 1 will be described assuming that the plurality of slave devices include a first slave device 30, a second slave device 40, and a third slave device 50.

[0012] The master device 20 and the multiple slave devices (30, 40, 50) are capable of bidirectional communication, and the master device 20 outputs a control command to each of the slave devices (30, 40, 50) for driving a window opening / closing motor, and each of the slave devices (30, 40, 50) feeds back a motor drive amount corresponding to the actual window opening degree to the master device 20. Alternatively, each of the slave devices (30, 40, 50) sends a detection value of a motor current flowing in association with motor drive to the master device 20.

[0013] The first slave side device 30 includes a wireless communication module 31, an RS485 driver 32, an RS485 driver 33, a microcomputer 34, a first window opening / closing motor 35, and a connector 36. The second slave side device 40 includes a connector 41, an RS485 driver 42, a microcomputer 43, and a second window opening / closing motor 44. The third slave side device 50 includes a connector 51, an RS485 driver 52, a microcomputer 53, and a third window opening / closing motor 54.

[0014] The wireless communication module 31 of the first slave side device 30 is connected to a communication means such as an antenna, and is connected to be able to wirelessly communicate with the master side device 20. In this way, one slave side device 30 among the multiple slave side devices 30, 40, 50 includes a wireless communication module 31 that is able to receive data from the master side device 20 via wireless communication.

[0015] The microcomputer 34 of the first slave side device 30 is communicatively connected to the wireless communication module 31. The microcomputer 43 of the second slave side device 40 is communicatively connected to the wireless communication module 31. The microcomputer 53 of the third slave side device 50 is communicatively connected to the wireless communication module 31. In this manner, the multiple slave side devices 30, 40, 50 each include a microcomputer 34, 43, 53 communicatively connected to the wireless communication module 31.

[0016] In the first slave side device 30, the wireless communication module 31 and the RS485 driver 32 are connected to each other via a communication line L1 so as to be able to communicate serially. The RS485 driver 32 and the RS485 driver 33 are connected to each other via a communication line L2 so as to be able to communicate RS485. Both the RS485 driver 32 and the RS485 driver 33 have a data transmission function and a data reception function. The RS485 driver 33 and the microcomputer 34 are connected to each other via a communication line L3 so as to be able to communicate serially. The microcomputer 34 and the first window opening / closing motor 35 are connected to each other via a communication line L4. In this way, in one slave side device 30, the RS485 drivers 32 and 33 are provided as a pair of transmitting / receiving serial communication drivers between the wireless communication module 31 and the microcomputer 34, and RS485 communication is possible through the communication line L2 connecting the RS485 drivers 32 and 33 as a pair of transmitting / receiving serial communication drivers, and data received by the wireless communication module 31 can be sent to the microcomputer 34 in one slave side device 30 by serial communication.

[0017] In the first slave side device 30, a communication line L5 for RS485 communication branches off from the communication line L2. A connector 36 is connected to the communication line L5. A communication line L6 for RS485 communication extends from the connector 36. The communication line L6 is connected to a connector 41 of the second slave side device 40 and a connector 51 of the third slave side device 50.

[0018] In the second slave device 40, the connector 41 and the RS485 driver 42 are connected to each other via a communication line L10 so as to be able to communicate via RS485. The RS485 driver 42 has a data transmission function and a data reception function. The RS485 driver 42 and the microcomputer 43 are connected to each other via a communication line L11 so as to be able to communicate serially. The microcomputer 43 and the second window opening / closing motor 44 are connected to each other via a communication line L12.

[0019] In the third slave device 50, the connector 51 and the RS485 driver 52 are connected to each other via a communication line L20 so as to be able to communicate via RS485. The RS485 driver 52 has a data transmission function and a data reception function. The RS485 driver 52 and the microcomputer 53 are connected to each other via a communication line L21 so as to be able to communicate serially. The microcomputer 53 and the third window opening / closing motor 54 are connected to each other via a communication line L22.

[0020] In the first slave side device 30, a wireless communication module 31, an RS485 driver 32, an RS485 driver 33, a microcomputer 34, a connector 36, and communication lines L1, L2, L3, and L5 are mounted on the same board. In the second slave side device 40, a connector 41, an RS485 driver 42, a microcomputer 43, and communication lines L10 and L11 are mounted on the same board. In the third slave side device 50, a connector 51, an RS485 driver 52, a microcomputer 53, and communication lines L20 and L21 are mounted on the same board.

[0021] In this way, RS485 communication is enabled on the board and further branched. That is, the communication line L2 for RS485 communication branches off and is connected to microcomputers 43, 53 via RS485 drivers 42, 52 as serial communication drivers in other slave side devices 40, 50 among the multiple slave side devices 30, 40, 50. Data received by the wireless communication module 31 can then be sent by serial communication to the microcomputers 43, 53 in the other slave side devices 40, 50.

[0022] Next, the operation will be described. Data communication from the master device 20 to each of the slave devices 30, 40, 50 is performed as follows. First, the master device 20 outputs control command data. Then, the wireless communication module 31 of the slave device 30 receives the data. The received data is sent to the microcomputer 34 of the first slave device 30, the microcomputer 43 of the second slave device 40, and the microcomputer 53 of the third slave device 50 via RS485 communication. Then, the microcomputers 34, 43, 53 of the slave devices 30, 40, 50 that have received the operation command start driving the motors 35, 44, 54 to open and close the windows.

[0023] In this way, between the wireless communication module 31 and the microcomputer 34 in one slave side device 30, a communication line L2 connecting the RS485 drivers 32, 33 as a pair of transmitting and receiving serial communication drivers branches off and is connected to the microcomputers 43, 53 via the RS485 drivers 42, 52 as serial communication drivers in the other slave side devices 40, 50. The microcomputer 34 in the first slave side device 30 has a serial port P1, the microcomputer 43 in the second slave side device 40 has a serial port P2, and the microcomputer 53 in the third slave side device 50 has a serial port P3. As a result, the number of serial ports of each of the microcomputers 34, 43, 53 in the slave side devices 30, 40, 50 is "1", and the number of serial ports is reduced.

[0024] As shown by the imaginary lines in FIG. 1, the wireless communication module 80 and the RS485 driver 81 for the second slave device 40 are not required, and the wireless communication module 90 and the RS485 driver 91 for the third slave device 50 are not required. That is, a wireless communication module is not required for each of the slave devices 30, 40, and 50, and long cable wiring is not required. Furthermore, relay devices such as a gateway are not required, so that costs can be reduced. In addition, since the cable shown in FIG. 2 can be eliminated, wiring can be simplified. The microcomputer 401a connected to the wireless communication module 404 in FIG. 5 requires a serial port P400 for the wireless communication module and a serial port P401 for the RS485 driver, but in this embodiment shown in FIG. 1, the microcomputer 34 has one serial port P1, and the serial port P400 with the wireless communication module 404 in FIG. 5 and the serial port P401 with the RS485 driver 401b can be shared to form one serial port.

[0025] In this manner, by using RS485 communication instead of serial communication for communication between the wireless communication module 31 and the microcomputers 34, 43, and 53, it becomes possible to send data received by one wireless communication module 31 to each of the microcomputers 34, 43, and 53 via RS485 communication. The "wireless communication" here can be applied to various communication standards. Serial communication is short-distance communication (basically communication used within a board). RS485 communication is resistant to noise and allows long-distance communication.

[0026] The details are explained below. When the master side controls each slave side device (motor) by communication, conventionally, in FIG. 2, the device is controlled by RS485 communication (wired), in FIG. 3, the device is controlled by wireless communication, and in FIG. 4, data from the master side device 300 by wireless communication is received by a relay device such as a gateway 304, and the data is transmitted to the RS485 driver 305 via a microcomputer 304a and the device is controlled by RS485 communication via wires, connectors, etc. In FIG. 5, data is received by wireless communication and the device is controlled (no gateway). In such a conventional method, when wireless communication is used, a wireless communication module is required for each slave side device. Also, when RS485 communication is used, a relay device such as a gateway is required. Even when a relay device is not used as in FIG. 5, the microcomputer 401a in the slave side device needs serial ports P400 and P401 for the wireless communication module and the RS485 driver.

[0027] In this embodiment, wireless communication data is converted to RS485 communication and branched to control each device, thereby reducing the number of components such as wireless communication modules and relay devices while suppressing communication costs. That is, in Fig. 1, branching is possible by RS485 communication between the wireless communication module 31 and the microcomputer 34, and one wireless communication module can receive data and control multiple devices by RS485 communication.

[0028] According to the above embodiment, the following effects can be obtained. (1) In a configuration of a communication system 10 including a master device 20 and a plurality of slave devices 30, 40, 50, one of the slave devices 30, 40, 50 includes a wireless communication module 31 capable of receiving data from the master device 20 via wireless communication. The slave devices 30, 40, 50 each include a microcomputer 34, 43, 53 connected to the wireless communication module 31 so as to be able to communicate data with each other. In one slave side device 30, RS485 drivers 32, 33 are provided between the wireless communication module 31 and the microcomputer 34 as a pair of transmitting and receiving serial communication drivers, and data received by the wireless communication module 31 is sent by serial communication to the microcomputer 34 in one slave side device 30 through a communication line L2 connecting the RS485 drivers 32, 33 as a pair of transmitting and receiving serial communication drivers, and a line branching from the communication line L2 is connected to the microcomputers 43, 53 via RS485 drivers 42, 52 as serial communication drivers in other slave side devices 40, 50 among the multiple slave side devices 30, 40, 50, and data received by the wireless communication module 31 is sent by serial communication to the microcomputers 43, 53 in the other slave side devices 40, 50. This makes it possible to reduce the number of serial ports of the microcomputers 34, 43, 53 in the slave side devices 30, 40, 50.

[0029] (2) The pair of transmitting and receiving serial communication drivers (32, 33) and the serial communication drivers (42, 52) in the other slave devices 40, 50 are RS485 drivers. Therefore, by using RS485 communication, it becomes more resistant to noise and enables long-distance communication.

[0030] The embodiment is not limited to the above, and may be embodied as follows, for example. The number of slave devices may be two or more. Although bidirectional communication is possible between the master device 20 and the multiple slave devices (30, 40, 50), the present invention is not limited to this and may be unidirectional (one-way) communication in which communication is only possible from the master device 20 to the multiple slave devices (30, 40, 50). When performing this unidirectional (one-way) communication, instead of an RS485 driver, an RS422 driver, for example, may be used as the pair of transmitting / receiving serial communication drivers (32, 33) and the serial communication drivers (42, 52) in the other slave devices 40, 50.

[0031] In short, the system configuration must be such that at least a master device can communicate with a plurality of slave devices. In FIG. 1, motors 35, 44, and 54 are used as actuators, but devices other than motors may also be used.

[0032] Although the present invention has been applied to a window opening and closing device in an agricultural greenhouse, it may be applied to communication systems in other agricultural fields. Furthermore, the present invention may be applied to communication systems used in general industrial equipment other than agricultural communication systems, such as a communication system in a device for driving a solenoid valve. [Explanation of symbols]

[0033] 10...communication system, 20...master side device, 30...first slave side device, 31...wireless communication module, 32...RS485 driver, 33...RS485 driver, 34...microcontroller, 40...second slave side device, 42...RS485 driver, 43...microcontroller, 50...third slave side device, 52...RS485 driver, 53...microcontroller, L2...communication line.

Claims

1. A communication system including a master device and a plurality of slave devices, one of the plurality of slave-side devices includes a wireless communication module capable of receiving data from the master-side device by wireless communication, and a microcomputer mounted on the same substrate as the wireless communication module; each of the plurality of slave devices includes another microcomputer connected to the wireless communication module so as to be capable of data communication; a pair of transmitting and receiving serial communication drivers is provided between the wireless communication module and the microcomputer in the one slave side device and within the same board, data received by the wireless communication module is sent by serial communication to the microcomputer in the one slave side device through a communication line connecting the pair of transmitting and receiving serial communication drivers, and a communication line is branched off from the communication line and connected to another microcomputer in another slave side device among the plurality of slave side devices via another serial communication driver, so that data received by the wireless communication module is sent by serial communication to the other microcomputer in the other slave side device; the pair of transmitting and receiving serial communication drivers and the other serial communication driver in the other slave device are a pair of RS485 drivers and another RS485 driver, a motor is connected to each of the microcomputer and the other microcomputer; A communication system characterized in that one of the pair of RS485 drivers provided in one of the slave side devices sends a control command for driving a motor from the master side device received by the wireless communication module to the other of the pair of RS485 drivers connected to the microcontroller and to the other RS485 driver connected to the other microcontroller.

2. 2. The communication system according to claim 1, wherein the one slave device has a communication line connecting the pair of RS485 drivers, a communication line for RS485 communication branched off from the communication line connecting the pair of RS485 drivers, and a connector connected to the communication line for RS485 communication mounted on the same board.

3. A communication system including a master device and a plurality of slave devices, one of the plurality of slave-side devices includes a wireless communication module capable of receiving data from the master-side device by wireless communication, and a microcomputer mounted on the same substrate as the wireless communication module; each of the plurality of slave devices includes another microcomputer connected to the wireless communication module so as to be capable of data communication; a pair of transmitting and receiving serial communication drivers is provided between the wireless communication module and the microcomputer in the one slave side device and within the same board, data received by the wireless communication module is sent by serial communication to the microcomputer in the one slave side device through a communication line connecting the pair of transmitting and receiving serial communication drivers, and a communication line is branched off from the communication line and connected to another microcomputer in another slave side device among the plurality of slave side devices via another serial communication driver, so that data received by the wireless communication module is sent by serial communication to the other microcomputer in the other slave side device; the pair of transmitting and receiving serial communication drivers and the other serial communication driver in the other slave device are a pair of RS485 drivers and another RS485 driver, A communication system characterized in that one of the slave side devices has a communication line connecting the pair of RS485 drivers, a communication line for RS485 communication branched off from the communication line connecting the pair of RS485 drivers, and a connector connected to the communication line for RS485 communication implemented on the same board.

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