CN103825883A - Multi-protocol conversion equipment based on wireless ZigBee, CAN bus and MODBUS/TCP and realization method thereof - Google Patents

Abstract

The invention discloses a multi-protocol conversion device and its realization method for introducing a wireless ZigBee network based on the IEEE802.15.4 standard to CAN bus and MODBUS/TCP industrial Ethernet. The device of the invention includes: a microprocessor and a ZigBee wireless master station , CAN bus station and MODBUS/TCP slave station, the microprocessor is used as the control center of the equipment to complete the analysis and distribution of information between different protocols; the Ethernet physical layer chip is connected to the microprocessor through the MII interface, and a MODBUS/ TCP slave station module; connect with CAN controller through input bus RX and output bus TX to construct CAN bus master station module; choose wireless radio frequency chip CC2530 as the ZigBee wireless master station of the device and connect with microprocessor through USART for data exchange; The multi-protocol conversion method of the present invention completes the data conversion among the three protocols of wireless ZigBee network, CAN bus and MODBUS/TCP Ethernet by opening an address conversion mapping table, and realizes a wireless/wired heterogeneous control network.

Description

Multi-protocol conversion device and its realization method based on wireless ZigBee, CAN bus and MODBUS/TCP

technical field

The invention relates to a multi-protocol conversion device for introducing a wireless ZigBee network based on the IEEE802.15.4 standard into a CAN-bus field bus and a MODBUS/TCP industrial Ethernet and a method for realizing multi-protocol conversion. the

Background technique

Fieldbus is a digital communication system that implements two-way serial multi-nodes between the production site and computerized measurement and control equipment. It is also known as an open, digital, and multi-point communication underlying control network. The appearance of the field bus has changed the point-to-point contact between the traditional field instrument device and the main control system, reduced the layout of the field bus cables, and saved the construction cost of the project; at the same time, with the intelligent development of the field instrument device, it is possible to realize the The control function of the system makes the structure of the control system highly decentralized. After decades of development, fieldbus technology has formed a multi-standard coexistence situation. Although fieldbus has the advantages of good real-time performance and high stability, the existing various fieldbuses have low transmission rates and limited transmission distances. The problem, and the fieldbus standards are not compatible with each other, which brings great inconvenience to the integration of the system and the use and maintenance of the user. the

MODBUS/TCP Industrial Ethernet is an extension of MODBUS. The physical layer and data link layer of the protocol are based on Ethernet and standard TCP/IP protocol, while the definition of the application layer is common to other protocols in the MODBUS protocol family. On the other hand, because of its openness and transparency, MODBUS has been widely supported by the industry and has become the de facto standard in the industry. In the ZigBee wireless data transmission network based on the IEEE802.15.4 standard, the radio frequency transmission cost between nodes is low and the distance is short, and each node only needs a small amount of energy to realize one-to-two and multi-point peer-to-peer communication. Moreover, ZigBee wireless network has functions such as fast networking and automatic configuration, which is suitable for industrial monitoring systems with complex and harsh environments. CAN bus technology is a multi-master serial communication method that effectively supports distributed control and real-time control. It has excellent stability, real-time performance, long-distance communication capabilities, and super hardware CRC error correction. High reliability has been widely used in the field of automatic control, and is recognized as one of the most promising field buses. The CAN bus and ZigBee wireless network are combined to form a mobile distributed network system, and the communication with the upper computer control information is realized through the MODBUS/TCP industrial Ethernet, which is more conducive to the flexibility and real-time performance of industrial detection. the

After searching the existing technical documents, it is found that the Chinese patent publication number is: CN1697448, the publication date was November 16, 2005, and the name is: multi-protocol conversion between MODBUS/TCP industrial Ethernet and equipment network fieldbus and ProfibusDP fieldbus Method and device, the application discloses the application layer protocol conversion among MODBUS/TCP industrial Ethernet, DeviceNet field bus and ProfibusDP field bus; Protocol conversion method and device between /TCP industrial Ethernet and ProfibusDP field bus, this application discloses the protocol conversion between MODBUS/TCP industrial Ethernet and ProfibusDP field bus; The weak point of above two kinds of methods is: all do not involve to industrial wireless network applications. The Chinese patent publication number is: CN101425948, the publication date was May 6, 2009, and the name is: Multi-protocol gateway and protocol conversion method for industrial wireless network access to industrial Ethernet and field bus. a's industrial wireless network, and the microcontroller realizes the protocol conversion among the three networks of MODBUS/TCP industrial Ethernet, ProfibusDP field bus and industrial wireless network. But none of the above patents involves the realization of the multi-protocol conversion method and device between MODBUS/TCP industrial Ethernet, industrial wireless network and CAN bus in the same device. After searching the existing technical literature, it is also found that "Industrial and Mine Automation" 2010 1671-251X (2010) 11-0101-05, the name is the design of multi-protocol conversion gateway for mining, and an embedded multi-protocol conversion gateway for mining is proposed. The design scheme of the protocol conversion gateway, which solves the data exchange problem of various underground networks through the organic combination of CAN bus network, industrial Ethernet and 802.11 network, but this method does not involve MODBUS/TCP Ethernet communication And the wireless ZigBee technology, and the protocol conversion method does not use the communication protocol to open the address conversion mapping table to realize the protocol conversion function. the

Contents of the invention

The invention overcomes the shortcomings in the prior art, and provides a wireless multi-protocol device and a protocol conversion method for introducing a wireless ZigBee network based on the IEEE802.15.4 standard to MODBUS/TCP industrial Ethernet and CAN bus. the

The invention introduces the industrial wireless network on the basis of the existing industrial Ethernet and the field bus, and realizes the wired/wireless heterogeneous network control technology. The present invention can not only connect intelligent devices such as sensors and actuators with wired interfaces in the field to the control network, but also connect wireless communication devices to the control network to expand the network control scale of the devices, thereby realizing a unified system protocol Complete wired and wireless seamless connection within the architecture. the

The wireless ZigBee network based on the IEEE802.15.4 standard is an industrial wireless local area network standard. It can realize short-distance, low-power wireless communication for cheap, fixed, convenient or mobile devices. It has been widely used in wireless sensor networks in recent years. The Modbus protocol was first developed by Schneider in 1978. At that time, it was mainly used as a communication language on electronic controllers to realize communication between controllers, controllers, networks and other devices. Support traditional RS232/RS485 and the latest development of Ethernet equipment. In 1996, Schneider introduced the TCP/IP-based Modbus protocol, which is a low-cost solution suitable for various applications and has been widely used in automation equipment; CAN bus technology (Controller Area Network) is the control Device LAN is one of the most widely used open field buses in the world. As a remote network communication control method with advanced technology, high reliability, complete functions and reasonable cost, CAN bus has been widely used in various automatic control systems. As an industrial field bus, CAN bus disperses the routine test and control functions of the host computer in the traditional distributed control system structure to each node in the field to complete, so as to realize higher-level control and management functions. Based on the wireless ZigBee network standard of IEEE802.15.4, the MODBUS/TCP industrial Ethernet protocol and the CAN bus protocol all adopt different standards in the physical layer and the data link layer. In order to realize the exchange of data between these three kinds of protocols, the present invention proposes The multi-protocol conversion equipment in the wireless heterogeneity should not only meet the requirements of the physical layer and data link layer of each protocol, but also define the application layers of different protocols separately. the

In order to solve the above-mentioned technical problems that exist, one of the purposes of the present invention is achieved through the following technical solutions:

A multi-protocol conversion device (hereinafter referred to as: multi-protocol conversion device) that introduces a wireless ZigBee network based on the IEEE802.15.4 standard to CAN bus and MODBUS/TCP industrial Ethernet. The multi-protocol conversion device includes: microprocessor, ZigBee Wireless master station, CAN bus master station, MODBUS/TCP slave station, Ethernet physical layer interface chip and RJ45 network port; Described microprocessor is the control center of whole equipment, adopts STM32F107 series chip, and it includes Ethernet MAC layer The controller, CAN controller and USART serial interface support Ethernet, CAN bus and RS485 bus expansion, and can complete the analysis and distribution of information between different protocols; the ZigBee wireless master station uses the CC2530 radio frequency chip to complete the wireless protocol Processing, connected with the microprocessor through the USART serial interface, and written the control program of the wireless master station, thereby establishing a wireless master station module, realizing the introduction of the wireless ZigBee network into the CAN bus master station and MODBUS/ In the industrial Ethernet of the TCP slave station; the Ethernet physical layer interface chip selects the DP83848 chip as the physical layer chip of the equipment, inserts the described microprocessor through the MII interface, and writes the described MODBUS/TCP The slave station program thus establishes a MODBUS/TCP slave station module, and realizes the MODBUS/TCP master-slave communication with the remote computer through the RJ45 network port;

The interface chip between described CAN controller and the described CAN bus master station selects SN65VHD230 chip, is connected with CAN controller by input bus RX and output bus TX, realizes the master station module of a CAN bus master station; The ZigBee wireless master station described above realizes introducing the wireless ZigBee network into the CAN bus and MODBUS/TCP industrial Ethernet; the CAN bus master station realizes the CAN bus network based on polling by defining the application layer protocol communication mode. the

Another object of the present invention is achieved by the following technical solutions: a kind of wireless ZigBee network based on IEEE802.15.4 standard is introduced into the realization method of the multi-protocol conversion of CAN bus and MODBUS/TCP industrial ethernet, adopts described A kind of wireless ZigBee network based on IEEE802.15.4 standard is introduced into the multi-protocol conversion equipment of CAN bus line and MODBUS/TCP industrial ethernet to carry out protocol conversion, this method comprises: Realize ZigBee wireless network based on IEEE802.15.4 standard by ZigBee wireless main station Communication, the CAN bus master-slave communication is realized by the CAN bus polling method, the MODBUS/TCP communication is realized by the MODBUS/TCP slave memory area mapping, and the three protocols are realized by the microcontroller by establishing the address conversion mapping area Data conversion; its specific content includes the following steps:

The first step is to initialize the multi-protocol conversion device:

(1) Microprocessor initialization;

(2) The microprocessor reads in the network configuration parameters through the RS232 interface;

(3) ZigBee wireless master module initialization;

(4) CAN bus master module initialization;

(5) MODBUS slave module initialization;

(6) Create a structure array for address translation between different protocols, and initialize the address translation mapping table according to network configuration parameters;

(7) ZigBee master station polling and protocol conversion

(8) CAN bus master station polling and protocol conversion;

(9) Master-slave communication between MODBUS/TCP slave station and remote computer;

(10) Return to step (7) and proceed in a loop. the

The second step is to establish a protocol conversion model in the system by defining the application layer of each protocol to realize the protocol conversion between wireless/wired and wired protocols; in this protocol conversion system, in order to realize the seamless upgrade of the field bus, define Both the wireless ZigBee network and the CAN bus based on the IEEE802.15.4 standard have a master station for their own network communication, which can simultaneously and independently complete the polling of the sub-node data in their respective networks; For data information, an address conversion mapping area can be opened up in the memory of the microprocessor, and the corresponding address information of all sub-nodes in the wireless ZigBee network and CAN bus can be stored in advance when communicating with other networks; in the MODBUS/TCP industrial Ethernet network, The multi-protocol conversion device and the remote computer form the MODBUS master-slave protocol stack. The multi-protocol conversion device, as a transparent slave station, realizes the data query of the sub-nodes in the wireless ZigBee network and CAN bus by receiving the control instructions from the host computer;

The transparent slave station refers to that the multi-protocol conversion device itself does not have the address identification information of the MODBUS slave station, and the device performs corresponding parsing and forwarding through the address conversion mapping area for the address information carried by the remote master station;

The third step is to complete the data exchange between different protocols by establishing an address translation mapping area as follows:

When the microprocessor starts to initialize, a part of the memory is reserved as the address translation mapping area; when the ZigBee wireless network and the CAN bus network are initialized, an array of address structures is defined in the address translation mapping area, and the address structure is configured through the network configuration parameters The array is initialized, the address conversion mapping table is established, and the corresponding relationship between the addresses of the ZigBee wireless network and the CAN bus network node is defined: the process of completing a data transmission by querying the address conversion mapping table is as follows:

(1) First, the host computer sends the control command to the microcontroller through the MODBUS/TCP network. The microcontroller analyzes the address identification information in the MODBUS and compares it with the address translation mapping table to determine which subnetwork the destination address is in. , judge whether it is necessary and repackage the actual communication address into the control instruction;

(2) If the destination address of the command points to the ZigBee network, it is sent to the ZigBee wireless master station through the USART interface, and the ZigBee wireless master station directly issues a control command to process the data of the corresponding child node;

(3) If the destination address pointed to by the instruction belongs to the child node of the CAN bus network, it is directly forwarded to the corresponding node through the CAN bus controller. the

Compared with prior art, technical scheme of the present invention has following advantage:

(1) The microprocessor is connected to the wireless signal radio frequency chip CC2530 of the ZigBee master station through the USART, realizing the introduction of the wireless ZigBee network based on the IEEE802.15.4 standard into the multi-protocol conversion system of MODBUS/TCP industrial Ethernet and CAN bus, and solving Solved the problems of secondary deployment and wireless upgrade of equipment in the actual industrial application of fieldbus;

(2) The MODBUS/TCP industrial Ethernet used in the present invention is a simple and efficient control scheme, which is easy to interconnect various systems. In this scheme, a variety of address conversion mapping tables can be developed through the MODBUS/TCP communication protocol. Conversion between protocols in the communication system;

(3) In the present invention, the CAN bus master-slave communication is completed by the CAN bus polling mode, and a multi-master serial communication mode that effectively supports distributed control and real-time control is realized, and then the CAN bus and the ZigBee wireless network are combined, Composing a mobile distributed network system, the communication with the host computer control information is realized through MODBUS/TCP industrial Ethernet, which is more conducive to the flexibility and scalability of industrial monitoring. the

Description of drawings

Fig. 1 is a schematic diagram of the hardware structure of the multi-protocol conversion system of the example of the present invention. the

Fig. 2 is a flow chart of the main program of the multi-protocol conversion system of the example of the present invention. the

Fig. 3 is a flowchart of MODBUS/TCP Ethernet physical interface initialization of the example of the present invention. the

Fig. 4 is a flowchart of the initialization of the wireless signal radio frequency chip of the example of the present invention. the

FIG. 5 is an address conversion mapping table of the multi-protocol conversion system of the example of the present invention. the

Detailed ways

The specific implementation manners of the present invention will be further described in detail below in conjunction with the accompanying drawings and embodiments. The following examples are used to illustrate the present invention, but are not intended to limit the scope of the present invention. the

A preferred example of the present invention is described below in conjunction with accompanying drawing:

As shown in Figure 1, a kind of wireless ZigBee network based on IEEE802.15.4 standard realized by the present invention is introduced into the multi-protocol conversion equipment of CAN bus and MODBUS/TCP industrial Ethernet, and this equipment comprises MODBUS/TCP slave station, ZigBee wireless Master station, CAN bus master station; the microprocessor chooses STM32F107 chip as the control center of the equipment, connects ZigBee wireless signal radio frequency chip CC2530 through USART, and connects with CAN controller SN65VHD230 chip through input bus TX and output bus RX; Ethernet physical The interface uses the DP83848 chip as the physical layer chip of the device, and communicates with the remote MODBUS/TCP master station through the RJ45 network port. the

As the control center of the device, the microprocessor realizes the analysis and distribution of message information between different protocols by defining the program of the application layer. The microprocessor of the present invention selects STM32F107 series chips, and has abundant storage resources and fast kernel architecture. STM32 microcontroller has program memory (SRAM), flash program memory (FLASH), clock, reset, etc., 2 12-bit digital-to-analog converters, 7 timers and 9 communication interfaces, etc. The outstanding power consumption control performance of the STM32 microcontroller not only greatly reduces the power consumption of the microprocessor, but also improves the working efficiency of the device. the

The microprocessor is connected to the wireless signal radio frequency chip CC2530 of the ZigBee master station through the USART, and realizes the master-slave communication with other wireless nodes through the wireless ZigBee network. CC2530 is a wireless RF terminal that can run the Zigbee protocol. It has the advantages of high data processing efficiency and high accuracy. It can cooperate with RF front-ends such as power amplifiers to improve the receiving sensitivity and transmitting power of the chip. The physical and MAC layers of the ZigBee physical protocol stack are IEEE802.15.4 protocols. The IEEE802.15.4 physical layer defines three frequency bands of 868MHz, 915MHz, and 2.4GHz. Users can choose the appropriate data transmission frequency band and communication rate according to specific requirements. the

The microprocessor connects the CAN controller SN65VHD230 chip of the CAN bus master station through the input bus TX and the output bus RX, and realizes master-slave communication with other devices on the CAN bus as the CAN bus master station. the

Microprocessor STM32F107 series chips include Ethernet MAC layer controller, and the Ethernet physical interface uses DP83848 chip as the physical layer chip of the device, which is connected to the microprocessor through the MII interface. The device of the present invention is used as a MODBUS/TCP slave station, and realizes MODBUS/TCP master-slave communication with a remote computer through an RJ45 network port. The DP83848 chip can provide 10/100Mb/s data rate, not only low power consumption, single-channel high speed, high cost performance, but also has a common network interface, which can simplify the software and hardware development process. the

A kind of wireless ZigBee network based on IEEE802.15.4 standard that the present invention realizes as shown in Figure 2 is introduced into CAN bus and MODBUS/TCP industrial Ethernet multi-protocol conversion equipment and its implementation method, the method comprising: by ZigBee wireless master station Realize ZigBee master-slave communication based on IEEE802.15.4 standard, realize CAN bus master-slave communication by CAN bus polling mode, realize MODBUS/TCP communication by mapping MODBUS/TCP slave memory area, and realize by establishing address conversion mapping area Data conversion between the three protocols. The main program flow of the device is as follows:

(1) Microprocessor initialization;

(2) The microprocessor reads in the network configuration parameters through the RS232 interface;

(3) ZigBee wireless master module initialization;

(4) CAN bus master module initialization;

(5) MODBUS slave module initialization;

(6) Create a structure array for address translation, and initialize the address translation mapping table according to the network configuration parameters;

(7) ZigBee master station polling and protocol conversion;

(8) CAN bus master station polling and protocol conversion;

(9) Master-slave communication between MODBUS/TCP slave station and remote computer;

(10) Return to step (7) and proceed in a loop. the

As shown in Figure 3, before the MODBUS slave module starts to work normally, it is necessary to initialize the DP83848 Ethernet physical interface chip, including initializing the MII interface of the STM32 microprocessor, and then reset the DP83848 Ethernet physical interface chip. Initialize the DP83848 Ethernet physical interface chip through the MDIO interface of STM32, configure the mode control register, and enable the receive/transmit interrupt of the MII interface. Finally, enter the main program of the protocol to make the MODBUS/TCP slave module work normally. The specific initialization steps are as follows;

(1) Initialize the MII interface of the STM32 microprocessor;

(2) Reset the DP83848 Ethernet physical layer interface chip through the microprocessor;

(3) Initialize the DP83848 Ethernet physical layer interface chip through the MDIO interface of the microprocessor, and configure the mode register in the Ethernet physical layer interface chip;

(4) Enable data receiving/sending interrupts through the microprocessor;

(5) Enter the MODBUS/TCP protocol entry program, make the MODBUS/TCP slave station enter the normal working state, and establish master-slave communication with the remote computer through Ethernet. the

As shown in Figure 4, before the ZigBee wireless master module works normally, the wireless signal radio frequency chip CC2530 needs to be initialized, including initializing the USART interface of the STM32F107 chip, resetting the wireless signal radio frequency chip CC2530, enabling the internal clock of the chip, and configuring the registers. Access mode, set data sending and receiving mechanism, check mode, enable receiving/sending interrupt, etc. Finally, start the wireless signal radio frequency chip CC2530, so that the master station starts to run normally. The specific initialization steps are as follows:

(1) Initialize the USART interface of the STM32F107 chip and reset the wireless signal RF chip CC2530 through the microprocessor;

(2) Enable the internal clock of the wireless signal RF chip, configure the access mode of the registers in the wireless signal RF chip, set the data sending and receiving mechanism, and enable wireless receiving/sending interrupts, etc.;

(3) Configure the parameters of the wireless signal RF chip by the program;

(4) Start the wireless signal radio frequency chip CC2530 wireless transceiver, and the wireless master station enters the normal operation state. the

After the ZigBee wireless master module works normally, the ZigBee wireless master module automatically establishes a connection with other wireless ZigBee devices to form a wireless ZigBee network for master-slave communication, and the wireless slave devices within the network actively report their wireless communication addresses and actual node addresses , so as to establish an address mapping relationship in the memory of the protocol conversion device. the

As shown in Figure 5, the realization of the address conversion mapping table opened for multi-protocol conversion in the present invention: the protocol conversion device of the present invention does not possess actual physical address itself, but realizes data in different by setting up a multi-protocol address mapping table transfer between protocols. In MODBUS communication, the MODBUS station number is used to distinguish different devices. In the ZigBee network, the ZigBee network address is used to distinguish different devices. In the CAN bus transmission, the identifier of the message information is used to realize the data receiving and sending. By establishing an address mapping table, devices on different networks can use a unified logical address to transmit data. the

After the MODBUS slave module works normally, establish MODBUS/TCP master-slave communication with the remote computer through Ethernet, and at the same time configure parameters through the network, and pre-store the MODBUS slave node address in the address conversion table. As shown in Figure 5(a)(b), suppose the current MODBUS slave node address is 0X01-0X0C. the

After the ZigBee wireless network establishes master-slave communication by the address in the wireless network of the device, by reading the actual address parameters in the address encoder, the actual node identification address is assigned to the wireless slave station nodes in the wireless network, so that each wireless slave station node Has a unique actual node identification address. And correspond to the node address of MODBUS slave station one by one. Before the ZigBee wireless master station starts to poll the slave station for data, it needs to update the address conversion mapping area in the microprocessor according to the address of the slave station node in the ZigBee network, and establish the ZigBee slave station node address and MODBUS slave station node address There is a one-to-one correspondence between them, as shown in Figure 5(a). the

The devices on the CAN bus realize data transmission through CAN-bus (a multi-master serial communication bus). There is no source address for sending data and destination address for receiving data in the message, but an identifier to indicate the data. Capability information and priority information. In the present invention, the CAN bus passes through the CAN-bus extended frame with 29 identifiers, adopts the expression mode of redefining the data frame function, realizes the communication of the CAN bus master and slave stations in the bus polling mode, and establishes the slave station nodes on the CAN bus The one-to-one relationship between the address and the MODBUS slave node address is shown in Figure 5(b). the

The process of data transmission between different protocols through the address conversion mapping table is as follows: the remote computer sends the data transmission instruction to the microprocessor through Ethernet, and the source address and destination address of the data frame in the instruction are both MODBUS slave stations The node address is defined by querying the corresponding relationship between the MODBUS slave node address and the ZigBee slave node address in the address conversion mapping table, and the MODBUS slave node address and the slave node address on the CAN bus. Finally, the data transmission is completed according to the corresponding actual address. For example, if the source address in the transmitted data frame is expressed as 0X02 by the node address of the MODBUS slave station, it can be known by querying the address conversion mapping table that the source address in the data frame is 0X0002 in the node address of the ZigBee slave station; if the transmitted data The destination address in the frame is 0X0B. By querying the address conversion mapping table, the corresponding address is 0X0005 of the slave node address on the CAN bus. Finally, the transmission of data frames between different networks can be realized. the

Claims (2)

1. a multiprotocol conversion equipment that the wireless ZigBee-network based on IEEE802.15.4 standard is incorporated into CAN bus and MODBUS/TCP Industrial Ethernet, is characterized in that: this multiprotocol conversion equipment comprises: microprocessor, ZigBee is wireless main website, CAN bus master, MODBUS/TCP slave station, ethernet physical layer interface chip and RJ45 network interface; Described microprocessor is the control centre of whole equipment, adopt STM32F107 family chip, it comprises ethernet mac layer controller, CAN controller and USART serial interface, support Ethernet, CAN bus and the expansion of RS485 bus, can complete parsing and the distribution of information between different agreement; Described ZigBee is wireless, and main website adopts CC2530 radio frequency chip to complete the processing of wireless protocols, be connected with described microprocessor by USART serial interface, and write the control program of wireless main website, thereby set up a wireless master station module, realized wireless ZigBee-network is incorporated in the Industrial Ethernet of CAN bus master and MODBUS/TCP slave station; Described ethernet physical layer interface chip is selected the physical chip of DP83848 chip as equipment, by the described microprocessor of MII interface access, thereby and write described MODBUS/TCP slave station program and set up the slave station module of a MODBUS/TCP, realize and the MODBUS/TCP master-slave communication of remote computer by described RJ45 network interface;

Interface chip between described CAN controller and described CAN bus master is selected SN65VHD230 chip, is connected with output bus TX by input bus RX with CAN controller, realizes the master station module of a CAN bus master; Realize wireless ZigBee-network is incorporated in CAN bus and MODBUS/TCP Industrial Ethernet by the wireless main website of described ZigBee; Described CAN bus master, realizes the CAN bus network based on poll by definition application layer protocol communication mode.

2. one kind is incorporated into the wireless ZigBee-network based on IEEE802.15.4 standard the implementation method of the multiprotocol conversion of CAN bus and MODBUS/TCP Industrial Ethernet, adopt described a kind of multiprotocol conversion equipment that the wireless ZigBee-network based on IEEE802.15.4 standard is incorporated into CAN bus and MODBUS/TCP Industrial Ethernet to carry out protocol conversion, the method comprises: realize the ZigBee wireless telecommunications based on IEEE802.15.4 standard by the wireless main website of ZigBee, realize the communication of CAN bus master-salve station by CAN bus polling mode, by the communication of MODBUS/TCP slave station memory field Mapping implementation MODBUS/TCP, and by setting up address transition map section, by the conversion of data between three agreements of microcontroller implementation, its particular content comprises the steps:

The first step is by multiprotocol conversion device initialize:

(1) microprocesser initialization;

(2) microprocessor reads in network configuration parameters by RS232 interface;

(3) the wireless master station module initialization of ZigBee;

(4) CAN bus master module initialization;

(5) MODBUS slave station module initialization;

(6) for the address transition between different agreement is opened up structure array, according to network configuration parameters, to the initialization of address transition mapping table;

(7) ZigBee main website poll and protocol conversion;

(8) CAN bus master poll and protocol conversion;

(9) master-slave communication of MODBUS/TCP slave station and remote computer;

(10) return to step (7), loop.

Second step, by the application layer of the each agreement of definition, is set up a protocol conversion model in system, realizes Wireless/wired and has a protocol conversion between wire protocol; In this protocol conversion system, for realizing the seamless upgrade of fieldbus, the wireless ZigBee-network of definition based on IEEE802.15.4 standard and CAN bus have a main website of network communication separately, can be simultaneously and complete independently the poll of antithetical phrase node data in each automatic network; In order to realize the data message of two master access the other side slave stations, can in the internal memory of microprocessor, open up address transition map section, store in advance all child nodes in wireless ZigBee-network and CAN bus with other network services time corresponding address information; In MODBUS/TCP Industrial Ethernet network, multiprotocol conversion equipment and remote computer composition MODBUS master-Slave Protocol stack, multiprotocol conversion equipment is realized the data query to child node in wireless ZigBee-network and CAN bus as transparent slave station by the control command that receives host computer;

Described transparent slave station refers to that multiprotocol conversion equipment itself does not possess MODBUS tributary address identifying information, and the address information that equipment carries for long-range main website, carries out corresponding parsing and forwarding by address transition map section;

To complete between different agreement the method for exchanges data as follows by setting up address transition map section for the 3rd step:

When microprocessor starts initialization, reserved a part of internal memory is as address transition map section; In the time of ZigBee wireless network and the initialization of CAN bus network, in an address structure body array of address transition map section definition, and by network configuration parameters to address structure array through row initialization, set up address transition mapping table, the corresponding relation of address between definition ZigBee wireless network and CAN bus network network node: changing mapping table by inquire address, to complete the process of a data transfer as follows:

(1) first host computer sends to microcontroller by MODBUS/TCP network by control command, microcontroller is by resolving the Address Recognition information contrast address transition mapping table in MODBUS, contrast address transition mapping table judges this destination address is in which kind of sub-network, judge whether to need and by actual mailing address Reseal in control command;

(2) if the destination address that this instruction is pointed to points to ZigBee-network, send to the wireless main website of ZigBee by USART interface, ZigBee is wireless, and main website directly issues control command that corresponding child node is carried out to data processing;

If if the destination address that this instruction is pointed to belongs to the child node of CAN bus network, be directly forwarded to respective nodes by CAN bus control unit.

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