Wireless networking system based on LoRa

Abstract

The invention belongs to the technical field of power distribution network information communication systems, and particularly relates to a wireless networking system based on LoRa. Comprising a terminal node, a routing node, a gateway node, a network node and a data center, the wireless networking system comprises a plurality of jumper networks, the basic structure of each jumper network is composed of a gateway node and a plurality of routing nodes, the gateway nodes and other nodes can perform bidirectional communication, and data messages can be forwarded to the gateway nodes for multiple times by the routing nodes and finally transmitted to a data center through the network nodes; the invention mainly relates to a wireless networking system based on LoRa, which is mainly used for a part of a power distribution network terminal communication system, and is used as a collecting and uploading channel for monitoring data of various terminals, the complexity of a terminal side communication structure is simplified, and a more perfect and efficient communication transmission system is established through a wireless communication mode.

Description

Technical Field

[0001] The present invention belongs to the technical field of information communication systems for power distribution networks, and in particular relates to a wireless networking system based on LoRa. Background Art

[0002] With the continuous improvement of the level of distribution network automation information technology, the basic operating status of the distribution network has been widely perceived through various terminal sensors and terminal monitoring equipment. The basic information obtained through these terminals can help the upper-level decision-making center obtain distribution network status information and complete load forecasting, planning and design, power supply optimization and other contents. At the same time, due to the continuous introduction of various functions, the number of terminal sensing devices used to obtain various types has also increased rapidly, which has led to the increasingly complex distribution network communication system. Various types and frequencies of sampled data need to be able to be transmitted to the data center in a timely and accurate manner, which has led to the increasing operating pressure of the distribution network communication system and the increasing complexity of the communication system, which is not conducive to the efficient and accurate transmission of large amounts of data. Summary of the invention

[0003] The purpose of the present invention is to provide a LoRa-based wireless networking system for simplifying the structure of the distribution network communication system, optimizing the data transmission method, and improving the communication efficiency based on the basic idea of ​​wireless communication technology.

[0004] To achieve the above object, the present invention adopts the following technical solution:

[0005] A LoRa-based wireless networking system of the present application includes a terminal node, a routing node, a gateway node, a network node, and a data center;

[0006] The wireless networking system includes several jumper networks. The basic structure of the jumper network consists of a gateway node and multiple routing nodes. The gateway node and other nodes can communicate bidirectionally. The data message can be forwarded by the routing node to the gateway node multiple times, and finally transmitted to the data center through the network node.

[0007] After the gateway node is powered on, it enters the receiving mode and waits for the information request from the routing node. After the routing node is powered on, it actively initiates a request to apply to join the network. The nodes closest to the gateway node enter the network first, and the nodes that have joined the network can receive and respond to the requests from other nodes that have not joined the network to join the network until a complete network is formed.

[0008] There is only one gateway node in a jumper network. Other nodes communicate data with the gateway node. Due to the limitation of communication distance, nodes far away from the gateway node need to be routed and forwarded by intermediate nodes to communicate with the gateway node. Each node in the network will establish a list of target node addresses and save the addresses of all next-hop nodes in it. When a node receives a routing request packet, it will establish a reverse path to the sender of the routing request packet and forward the routing request to the neighboring node. When a node receives a routing request whose destination node address is itself, it will send a reply packet to the sender of the routing request. Since the routing request packet sent by the sender reaches the target node along a certain path, the routing reply packet can also reach the sender of the routing request in the reverse direction along the path. The node that forwards the routing request packet establishes a path to the receiver of the original routing request packet.

[0009] The network node is the central part of the wireless ad hoc network. Its main function is to establish and maintain the network information table of the entire network. After any node in the network successfully joins the network, it needs to send its own node information to the network node. The network node will add the addresses of all the nodes passed by to the route. After receiving the data packet, the network node will parse the data and write it into the information table. When the parent node of a node has an abnormality and cannot transmit data, the node will rediscover the route and send the new route request information to the network node. After receiving the information, the network node will update the network information table according to the route information in the information, so as to ensure the normal operation of the network.

[0010] The terminal node sends the terminal data to the wireless LoRa network through the 5.8G backbone Wifi communication link.

[0011] A further improvement or preferred implementation of the aforementioned wireless networking system based on LoRa, the terminal node is based on a design scheme of separating the MCU microcontroller and the RF radio frequency module, and the microcontroller and the wireless radio frequency transceiver each use a chip. In this application, it includes a microprocessor GD32F103VET6, an STM8L151 / 152 and a SX1278 wireless radio frequency module; the wireless data transceiver is composed of STM8L151 / 152 and SX1278, and the Rime protocol stack is used to implement functions such as routing networking; GD32F103VET6 implements system management, data acquisition packaging and analysis, and communicates with STM8L151 / 152 through a serial port, so that the terminal node communicates with the network system, and the terminal node collects the corresponding data information, which is processed by GD32F103VET6 and sent to STM8L151 / 152, and is packaged and uploaded through the LoRa wireless network in a single hop or multi-hop manner.

[0012] The STM8L151 / 152L microprocessor in the terminal node sets the working mode of the SPI module to the host mode, and determines whether the SPI sends or receives data through the high and low levels of the PB4 pin; the wireless node STM8L151 / 152L turns on the SPI communication function by setting the corresponding GPIO during the initialization process; after the host STM8L151 / 152L writes the data into the data register corresponding to its SPI module, it automatically starts the clock, and then shifts and sends the written data according to the hardware circuit SPI timing. The data is sent to the MISO pin of the SX1278 module through the MOSI pin, and finally sent out by the SX1278 radio frequency; the data transmission mode between SX1278 and STM8L151 / 152L is to transmit one byte at a time when sending data. Only when all the data are shifted out can the STM8L151 / 152L and the radio frequency module complete a data exchange.

[0013] As a further improvement or preferred implementation of the aforementioned wireless networking system based on LoRa, the wireless LoRa network adopts a Mesh multi-hop method to send the terminal data of collectors, sensors, etc. to the next hop node through the Mesh device on the tower, and then reaches the destination node, i.e. the gateway node, after several hops of forwarding, and finally transmits the data information to the monitoring management center through GPRS technology;

[0014] LoRa management system hardware: GD32F103VET6 processor, LoRa RF transceiver, GPRS module, WIFI module, RS485 interface and Ethernet interface;

[0015] GD32F103VET6 executes control actions and completes data parsing or packaging; LoRa RF transceiver realizes networking functions and data sending and receiving; GPRS enables the monitoring terminal aggregation node or central node to communicate with the monitoring management center server, thereby transmitting the on-site data of the transmission line back to the monitoring management center so that management personnel can understand the transmission status in a timely manner; the WIFI module is mainly used for network debugging of 5.8G wireless devices, network pan-tilt cameras and other network devices during on-site construction, and its function is turned off after debugging is completed; RS485 communicates with business equipment, such as sensor equipment; the Ethernet interface communicates with the wireless private network system power management motherboard to realize remote viewing of battery power information and system power management.

[0016] As a further improvement or preferred implementation of the aforementioned LoRa-based wireless networking system, the GPRS module adopts E840-TTL-GPRS03, and serial communication is adopted between the MCU and the GPRS module. Data transmission and sharing are realized through the GPRS network and the Internet. Simple AT commands are used for settings during use, so as to easily realize two-way transparent data transmission from the serial port to the network.

[0017] The LoRa-based wireless networking system according to claim 4 is characterized in that, in particular, the STM8L151 / 152L processor communicates bidirectionally with the SX1278 chip through a 4-wire SPI interface (SCK, MOSI, MISO, NSS); wherein the STM8L151 / 152L is the host, the SX1278 is the slave, the microprocessor reads the SX1278 RF chip status information in SPI mode, and the wireless data in the SX1278 FIFO register is read and written by interruption.

[0018] A further improvement or preferred implementation of the aforementioned wireless networking system based on LoRa is that the RF module of the system adopts a combination of ultra-low power consumption STM8L151 / 152 and SX1278. The STM8L151 / 152L runs an operating system and a protocol stack and improves the corresponding data interface for serial communication. The STM8L151 / 152L circuit uses its own 16M internal RC clock to provide a clock source for the RF part to minimize power consumption. The microprocessor GD32F103VET6 completes the acquisition and control functions of the entire power transmission monitoring system.

[0019] The connection diagram of SX1278 wireless module and STM8L151 / 152L circuit; DIO is the interrupt output pin of SX1278 chip, connected to the IO pin of STM8L151 / 152L; NRESET of SX1278 RF is connected to PC1 of STM8L151 / 152L and is valid at low level, NSS chip select pin is connected to PB4 of STM8L151 / 152L and is valid at low level, and PB5, PB6 and PB7 of SPI1 module of STM8L151 / 152L are connected to SCK, MOSI and MISO of SX1278 wireless module.

[0020] For further improvement or preferred implementation of the aforementioned LoRa-based wireless networking system, the SX1278 RF transceiver pins RF1_LF and PA_BOOST are the RF transceiver ports of the chip. A filtering circuit is added to the RF transceiver circuit to purify the receiving and transmitting signals. The RF receiving and transmitting circuits share an antenna through the PE4259 RF switch; the chip uses a 32M external crystal oscillator as the clock source, and filter capacitors are added to other digital power ports to stabilize the voltage; STM8L151 / 152L is used as a control chip, and a 32M external crystal oscillator is also used to provide a clock source. A debugging interface is reserved for debugging convenience, and a status indicator light is added to display the operating status.

[0021] A further improvement or preferred implementation of the aforementioned LoRa-based wireless networking system further includes a GD32F103VET6 peripheral circuit; specifically:

[0022] Power supply circuit: 3.3V voltage provides a stable voltage source through 3 linear voltage regulator chips; RS485 conversion circuit: The communication chip is MAX485ED, and the communication between the wireless node and the acquisition device is completed through USART3 of GD32F103VET6; External flash drive circuit: SPI serial flash W25Q64 chip is used as the system flash resource. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 This is a schematic diagram of a wireless networking system based on LoRa. DETAILED DESCRIPTION

[0024] The present invention is described in detail below in conjunction with specific embodiments;

[0025] The present application mainly relates to a LoRa-based wireless networking system, which is mainly used as part of the distribution network terminal communication system, and is used as a collection and upload channel for various terminal monitoring data, simplifies the complexity of the terminal side communication structure, and establishes a more complete and efficient communication transmission system through wireless communication.

[0026] like Figure 1 As shown, the LoRa-based wireless networking system of the present application mainly includes terminal nodes, routing nodes, gateway nodes, network nodes, and data centers;

[0027] The wireless networking system includes several jumper networks. The basic structure of the jumper network is composed of a gateway node and multiple routing nodes. The gateway node and multiple routing nodes constitute a wireless multi-hop network. The gateway node and other nodes can communicate bidirectionally. The data message can be forwarded by the routing node to the gateway node multiple times, and finally transmitted to the data center through the network node;

[0028] After the gateway node is powered on, it enters the receiving mode and waits for the information request from the routing node. After the routing node is powered on, it actively initiates a request to apply to join the network. The nodes closest to the gateway node enter the network first, and the nodes that have joined the network can receive and respond to the requests from other nodes that have not joined the network to join the network until a complete network is formed.

[0029] There is only one gateway node in a jumper network. Other nodes communicate data with the gateway node. Due to the limitation of communication distance, nodes far away from the gateway node need to be routed and forwarded by intermediate nodes to communicate with the gateway node. Each node in the network will establish a list of target node addresses and save the addresses of all next-hop nodes in it. When a node receives a routing request packet, it will establish a reverse path to the sender of the routing request packet and forward the routing request to the neighboring node. When a node receives a routing request whose destination node address is itself, it will send a reply packet to the sender of the routing request. Since the routing request packet sent by the sender reaches the target node along a certain path, the routing reply packet can also reach the sender of the routing request in the reverse direction along the path. The node that forwards the routing request packet establishes a path to the receiver of the original routing request packet.

[0030] The network node is the central part of the wireless ad hoc network. Its main function is to establish and maintain the network information table of the entire network. After any node in the network successfully joins the network, it needs to send its own node information to the network node. The network node will add the addresses of all the nodes passed by to the route. After receiving the data packet, the network node will parse the data and write it into the information table. When the parent node of a node has an abnormality and cannot transmit data, the node will rediscover the route and send the new route request information to the network node. After receiving the information, the network node will update the network information table according to the route information in the information, so as to ensure the normal operation of the network.

[0031] The terminal node sends the terminal data to the wireless LoRa network through the 5.8G backbone Wifi communication link;

[0032] The terminal node is based on the MCU microcontroller and RF radio frequency module separation design. The microcontroller and the wireless radio frequency transceiver each use a chip. In this application, it includes a microprocessor GD32F103VET6, STM8L151 / 152 and SX1278 wireless radio frequency module; the wireless data transceiver is composed of STM8L151 / 152 and SX1278, and the Rime protocol stack is used to realize functions such as routing networking; GD32F103VET6 realizes system management, data acquisition packaging and analysis, and communicates with STM8L151 / 152 through a serial port, so that the terminal node communication network system, the terminal node collects the corresponding data information, which is processed by GD32F103VET6 and sent to STM8L151 / 152, and is packaged and uploaded through the LoRa wireless network in a single hop or multi-hop manner;

[0033] In particular, the STM8L151 / 152L processor communicates bidirectionally with the SX1278 chip through a 4-wire SPI interface (SCK, MOSI, MISO, NSS); the STM8L151 / 152L is the host, the SX1278 is the slave, the microprocessor uses the SPI method to read the SX1278 radio chip status information, and the wireless data in the SX1278 FIFO register is read and written using an interrupt method;

[0034] In particular, the system's RF module uses a combination of ultra-low power STM8L151 / 152 and SX1278. The STM8L151 / 152L runs the operating system and protocol stack and provides the corresponding data interface for serial communication. The STM8L151 / 152L circuit uses its own 16M internal RC clock to provide the clock source for the RF part to minimize power consumption. The microprocessor GD32F103VET6 completes the acquisition and control functions of the entire power transmission monitoring system.

[0035] The connection diagram of the SX1278 wireless module and the STM8L151 / 152L circuit; DIO is the interrupt output pin of the SX1278 chip, connected to the IO pin of the STM8L151 / 152L; the reset pin NRESET of the SX1278 RF is connected to the PC1 of the STM8L151 / 152L and is valid at a low level, and the NSS chip select pin is connected to the PB4 of the STM8L151 / 152L and is valid at a low level, and the SPI1 module pins PB5, PB6, and PB7 of the STM8L151 / 152L are connected to the SCK, MOSI, and MISO of the SX1278 wireless module;

[0036] The STM8L151 / 152L microprocessor in the terminal node sets the working mode of the SPI module to the host mode, and determines whether the SPI sends or receives data through the high and low levels of the PB4 pin; the wireless node STM8L151 / 152L turns on the SPI communication function by setting the corresponding GPIO during the initialization process; after the host STM8L151 / 152L writes the data into the data register corresponding to its SPI module, it automatically starts the clock, and then shifts and sends the written data according to the hardware circuit SPI timing. The data is sent to the MISO pin of the SX1278 module through the MOSI pin, and finally sent out by the SX1278 radio frequency; the data transmission mode between SX1278 and STM8L151 / 152L is to transmit one byte at a time when sending data. Only when all the data are shifted out can the STM8L151 / 152L and the radio frequency module complete a data exchange;

[0037] In particular, the RF1_LF and PA_BOOST pins of the SX1278 RF transceiver are the RF transceiver ports of the chip. A filter circuit is added to the RF transceiver circuit to purify the receiving and transmitting signals. The RF receiving and transmitting circuits share an antenna through the PE4259 RF switch. The chip uses a 32M external crystal oscillator as the clock source, and filter capacitors are added to other digital power ports to stabilize the voltage. STM8L151 / 152L, as the control chip, also uses a 32M external crystal oscillator to provide the clock source. A debugging interface is reserved for debugging convenience, and a status indicator is added to display the operating status.

[0038] The wireless LoRa network adopts the Mesh multi-hop method to send the terminal data such as collectors and sensors to the next hop node through the Mesh device on the tower. After several hops, it reaches the destination node, i.e. the gateway node, and finally transmits the data information to the monitoring management center through GPRS technology.

[0039] LoRa management system hardware: GD32F103VET6 processor, LoRa RF transceiver, GPRS module, WIFI module, RS485 interface and Ethernet interface;

[0040] GD32F103VET6 executes control actions and completes data parsing or packaging; LoRa RF transceiver realizes networking functions and data sending and receiving; GPRS realizes the communication between the monitoring terminal aggregation node or central node and the monitoring management center server, so as to transmit the on-site data of the transmission line back to the monitoring management center so that the management personnel can understand the power transmission status in time; WIFI module is mainly used for network debugging of 5.8G wireless devices, network PTZ cameras and other network devices during on-site construction, and its function is turned off after debugging; RS485 communicates with business equipment, such as sensor equipment; Ethernet interface communicates with the wireless private network system power management mainboard to realize remote viewing of battery power information and system power management;

[0041] In particular, it also includes the GD32F103VET6 peripheral circuit; specifically:

[0042] The power supply circuit used to power the chip: specifically, the 3.3V voltage provides a stable voltage source through a 3 linear voltage regulator chip;

[0043] RS485 conversion circuit for communication conversion, including communication chip MAX485ED, completes the communication between wireless node and acquisition device through USART3 of GD32F103VET6;

[0044] It also includes an external flash driver circuit, including using a SPI serial flash memory W25Q64 chip as a system flash resource;

[0045] In this application, the GPRS module uses E840-TTL-GPRS03, and serial communication is used between the MCU and the GPRS module. Data transmission and sharing are realized through the GPRS network and the Internet. Simple AT commands are used to set up during use, so as to easily realize two-way transparent data transmission from the serial port to the network;

[0046] Finally, it should be noted that the above embodiments are only used to illustrate the technical solution of the present invention, rather than to limit the scope of protection of the present invention. Although the present invention has been described in detail with reference to the preferred embodiments, those skilled in the art should understand that the technical solution of the present invention can be modified or replaced by equivalents without departing from the essence and scope of the technical solution of the present invention.

Claims

1. A wireless networking system based on LoRa, characterized in that: Including terminal nodes, routing nodes, gateway nodes, network nodes, and data centers; The wireless networking system includes several jumper networks. The basic structure of the jumper network consists of a gateway node and multiple routing nodes. The gateway node and other nodes can communicate bidirectionally. The data message can be forwarded by the routing node to the gateway node multiple times, and finally transmitted to the data center through the network node. After the gateway node is powered on, it enters the receiving mode and waits for the information request from the routing node. After the routing node is powered on, it actively initiates a request to apply to join the network. The nodes closest to the gateway node enter the network first, and the nodes that have joined the network can receive and respond to the requests from other nodes that have not joined the network to join the network until a complete network is formed. There is only one gateway node in a jumper network. Other nodes communicate data with the gateway node. Due to the limitation of communication distance, nodes far away from the gateway node need to be forwarded by intermediate nodes before they can communicate with the gateway node. Each node in the network will establish a target node address list and save the addresses of all next-hop nodes in it. When a node receives a routing request packet, it will establish a reverse path to the sender of the routing request packet and forward the routing request to the neighboring node; when a node receives a routing request whose destination node address is itself, it will send a reply packet to the sender of the routing request; since the routing request packet sent by the sender reaches the target node along a certain path, the routing reply packet can also reach the sender of the routing request in the reverse direction along the path; The node forwarding the route request packet establishes a path leading to the receiver of the original route request packet; The network node is the central part of the wireless ad hoc network. Its main function is to establish and maintain the network information table of the entire network. After any node in the network successfully joins the network, it needs to send its own node information to the network node. The network node will add the addresses of all the nodes passed by to the route. After receiving the data packet, the network node parses the data and writes it into the information table. When an abnormality occurs in the upper node of a node and data cannot be transmitted, the node will rediscover the route and send new route request information to the network node. After receiving the information, the network node updates the network information table according to the route information in the information, thereby ensuring the normal operation of the network; The terminal node sends the terminal data to the wireless LoRa network through the 5.8G backbone Wifi communication link.

2. The wireless networking system based on LoRa according to claim 1, characterized in that: The terminal node is based on the design scheme of separating the MCU microcontroller and the RF radio frequency module. The microcontroller and the wireless radio frequency transceiver each use a chip. In this application, the microprocessor GD32F103VET6, STM8L151 / 152 and SX1278 wireless radio frequency module are included; the wireless data transceiver is composed of STM8 and SX1278, and the Rime protocol stack is used to realize functions such as routing networking; GD32F realizes system management, data collection packaging and analysis, and communicates with STM8 through a serial port, so that the terminal node communication network system, the terminal node collects the corresponding data information, which is processed by GD32F and sent to STM8, and is packaged and uploaded through the LoRa wireless network in a single hop or multi-hop manner; The STM8L microprocessor in the terminal node sets the working mode of the SPI module to the host mode, and determines whether the SPI sends or receives data through the high and low levels of the PB4 pin; the wireless node STM8L enables the SPI communication function by setting the corresponding GPIO during the initialization process; after the host STM8L writes the data into the data register corresponding to its SPI module, it automatically starts the clock, and then shifts and sends the written data according to the hardware circuit SPI timing. The data is sent to the MISO pin of the SX1278 module through the MOSI pin, and finally sent out by the SX1278 RF; the data transmission method between SX1278 and STM8L is shown in Figure 3-6. When sending data, one byte is transmitted at a time. Only when all the data is shifted out can the STM8L and RF module complete a data exchange.

3. The wireless networking system based on LoRa according to claim 2, characterized in that: The wireless LoRa network adopts the Mesh multi-hop method to send the terminal data such as collectors and sensors to the next hop node through the Mesh device on the tower. After several hops, it reaches the destination node, i.e. the gateway node, and finally transmits the data information to the monitoring management center through GPRS technology. LoRa management system hardware: GD32F processor, LoRa RF transceiver, GPRS module, WIFI module, RS485 interface and Ethernet interface; GD32F executes control actions and completes data parsing or packaging; LoRa RF transceiver realizes networking functions and data transmission and reception; GPRS enables the monitoring terminal aggregation node or central node to communicate with the monitoring management center server, thereby transmitting the transmission line field data back to the monitoring management center so that managers can understand the transmission status in a timely manner; The WIFI module is mainly used for network debugging of 5.8G wireless devices, network PTZ cameras and other network devices during on-site construction. Its function will be turned off after debugging is completed; RS485 communicates with business equipment, such as sensor equipment; the Ethernet interface communicates with the wireless private network system power management motherboard to realize remote viewing of battery power information and system power management.

4. The wireless networking system based on LoRa according to claim 3, characterized in that: The GPRS module uses E840-TTL-GPRS03. Serial communication is used between MCU and GPRS module. Data transmission and sharing are realized through GPRS network and Internet. Simple AT commands are used to set up and bidirectional transparent data transmission from serial port to network can be easily realized.

5. The wireless networking system based on LoRa according to claim 4, characterized in that: The STM8L processor communicates bidirectionally with the SX1278 chip through a 4-wire SPI interface (SCK, MOSI, MISO, NSS); the STM8L is the host and the SX1278 is the slave. The microprocessor uses SPI to read the status information of the SX1278 RF chip, and the wireless data in the SX1278 FIFO register is read and written using interrupts.

6. The wireless networking system based on LoRa according to claim 5, characterized in that: The RF module of the system adopts the combination of ultra-low power consumption STM8L151 / 152 and SX1278. The operating system and protocol stack are run on the STM8L and the corresponding data interface is provided for serial communication. The STM8L circuit uses its own 16M internal RC clock to provide the clock source for the RF part to minimize power consumption. The microprocessor GD32F completes the acquisition and control functions of the entire power transmission monitoring system. The connection diagram of SX1278 wireless module and STM8L circuit; DIO is the interrupt output pin of SX1278 chip, connected to the IO pin of STM8L; NRESET of SX1278 RF is connected to PC1 of STM8L and is valid at low level, NSS chip select pin is connected to PB4 of STM8L and is valid at low level, and PB5, PB6 and PB7 of SPI1 module of STM8L are connected to SCK, MOSI and MISO of SX1278 wireless module.

7. The LoRa-based wireless networking system according to claim 6, characterized in that: The RF1_LF and PA_BOOST pins of the SX1278 RF transceiver are the RF transceiver ports of the chip. A filter circuit is added to the RF transceiver circuit to purify the receiving and transmitting signals. The RF receiving and transmitting circuits share an antenna through the PE4259 RF switch. The chip uses a 32M external crystal oscillator as the clock source, and filter capacitors are added to other digital power ports to stabilize the voltage. STM8L, as a control chip, also uses a 32M external crystal oscillator to provide a clock source. A debugging interface is reserved for debugging convenience, and a status indicator light is added to display the operating status.

8. The wireless networking system based on LoRa according to claim 7, characterized in that: It also includes GD32F peripheral circuits; specifically: Power supply circuit: 3.3V voltage provides a stable voltage source through 3 linear voltage regulator chips; RS485 conversion circuit: The communication chip is MAX485ED, and the communication between the wireless node and the acquisition device is completed through USART3 of GD32F; External flash drive circuit: SPI serial flash memory W25Q64 chip is used as the system flash resource.

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