A reconfigurable can switch box device

Abstract

Due to the relative dispersion and long distance of each console group and each cabin position, the traditional CAN network networking technology often faces problems such as too complex bus topology, reduced reliability, limited number of connected nodes and long distance transmission. Therefore, a new reconfigurable CAN switch box device is proposed to meet the application scene requirements of multi-cabin console group networking. The application uses "CAN transceiver-isolator-CAN transceiver" and "CAN transceiver-isolator-optoelectronic module" to convert the CAN nodes of multiple console groups in the cabin into "single" nodes in terms of physical interface characteristics, and connect them to the CAN bus inside the reconfigurable CAN switch box device. For cabins or console groups that need long distance transmission, "CAN transceiver-isolator-optoelectronic module" is used to realize long distance transmission of data.

Description

TECHNICAL FIELD

[0001] The application belongs to the field of fieldbus technology, and particularly relates to a reconfigurable CAN exchange box device. BACKGROUND

[0002] The display and control console is an important part of the radar system, and is a key platform for input control and state display of the radar system. With the increasing complexity of the radar system, and in the background of multi-system linkage and cooperation, the function division of the display and control console is becoming more and more fine, and the number is also increasing, and gradually develops towards a display and control console group and a multi-cabin display and control console group. Therefore, the control instruction synchronization and state monitoring between the display and control console groups, and the requirements of reconfigurability and switchable master-slave devices are extremely urgent. The controller area network (CAN) can completely meet the networking requirements of the display and control console group due to its communication reliability, network broadcasting and multi-master control capability. However, the positions of each display and control console group and each cabin are relatively dispersed and far away, and the application of traditional CAN network networking technology often faces problems such as too complex bus topology, reduced reliability, limited number of connected nodes, long-distance transmission and the like. SUMMARY

[0003] Therefore, the application proposes a brand-new reconfigurable CAN exchange box device to meet the application scene requirements of the multi-cabin display and control console group, and can realize the following functions: 1) the basic working principle of the reconfigurable CAN exchange box device; 2) the master-slave mode switching implementation and functions of the reconfigurable CAN exchange box device; 3) the application topology of the reconfigurable CAN exchange box device; and 4) the basic protocol framework of the reconfigurable CAN exchange box device.

[0004] The basic working principle of the reconfigurable CAN exchange box device of the application is that the CAN nodes of the multiple display and control console groups inside the cabin are converted into a single node in terms of physical interface characteristics by using a CAN transceiver-isolator-CAN transceiver and a CAN transceiver-isolator-optoelectronic module, and are connected to the CAN bus inside the reconfigurable CAN exchange box device. For the cabin or display and control console group that needs long-distance transmission, the CAN transceiver-isolator-optoelectronic module is used to realize long-distance transmission of data.

[0005] Master-slave mode switching implementation and function of the reconfigurable CAN switch device: the reconfigurable CAN switch device has two working modes of master and slave, which can be flexibly switched through the dial code on the device. The reconfigurable CAN switch device working in the master mode, the built-in MCU collects bus data and packages it for external transmission, and can also respond to external instructions to distribute control instructions; the reconfigurable CAN switch device working in the slave mode, the built-in MCU only completes the listening work of the bus. In the CAN bus topology structure built by usually using multiple reconfigurable CAN switch devices, only one reconfigurable CAN switch device works in the master mode, and the remaining devices work in the slave mode.

[0006] Application topology of the reconfigurable CAN switch device: the internal CAN bus topology of a single reconfigurable CAN switch device is a daisy chain topology structure with the head connected to the tail. After using the reconfigurable CAN switch device, the CAN node networking of multiple display and control console groups in the cabin is a local small CAN bus network. From the physical interface characteristics, the external node can be regarded as a "single" node, therefore, for the networking of multiple cabin devices, the cabin bus can be arbitrarily connected to the main network (the CAN bus network where the master working mode reconfigurable CAN switch device is located), and the complex impedance matching calculation does not need to be considered.

[0007] Basic protocol framework of the reconfigurable CAN switch device: the reconfigurable CAN switch device defines control frames, state frames and heartbeat frames by using CANID and data frame parts on the basis of the standard CAN communication protocol.

[0008] The beneficial effects of the present application are

[0009] The complex networking problem of multiple device cabins is solved, and the impedance matching problem in the complex CAN bus topology is avoided, and the local CAN bus network is truly used as soon as it is connected. BRIEF DESCRIPTION OF DRAWINGS

[0010] Figure 1 It is a principle block diagram of the reconfigurable CAN switch device.

[0011] Figure 2 It is a master-slave mode switching schematic diagram of the reconfigurable CAN switch device.

[0012] Figure 3 It is an internal topology schematic diagram of the reconfigurable CAN switch device.

[0013] Figure 4 It is a networking topology schematic diagram of multiple reconfigurable CAN switch devices.

[0014] Figure 5 It is a protocol frame schematic diagram of the reconfigurable CAN switch device. DETAILED DESCRIPTION

[0015] The technical solutions in the embodiments of the present application will be clearly and completely described below. Obviously, the described embodiments are only a part of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all the other embodiments obtained by those skilled in the art without creative work fall within the protection scope of the present application.

[0016] As shown in the figure, the hardware of the present application mainly consists of five parts: MCU control circuit, master-slave identification circuit, "CAN transceiver-isolator-CAN transceiver" circuit, "CAN transceiver-isolator-optoelectronic module" circuit and CAN bus. The MCU control circuit is the central part of device data processing and control, which realizes the analysis and processing of bus data, external interaction and device control. The master-slave identification circuit realizes the identification of device master-slave mode setting. The "CAN transceiver-isolator-CAN transceiver" circuit realizes the interface conversion of the local CAN bus network where the device is located. The "CAN transceiver-isolator-optoelectronic module" circuit realizes the photoelectric conversion of the external interface of the device, mainly to meet the use of long-distance data transmission. The CAN bus topology circuit adopts daisy chain topology structure. Figure 1 As shown in the figure, the 8-bit DIP switch on the reconfigurable CAN exchange box device can set the master-slave working mode of the device, and also can set the CAN ID number of the device. The 1st-7th bits of the DIP switch correspond to the device CAN ID number, corresponding to the CAN ID number range of 0x00-0x7F; the 8th bit of the DIP switch corresponds to the working mode of the device, dialing to "ON" is the master working mode, dialing to "OFF" is the slave working mode, and the device defaults to the slave working mode. The device recognizes the DIP switch setting state during the initialization process after power-on, and sets the device.

[0017] Figure 2 As shown in the figure, the reconfigurable CAN exchange box device internally adopts daisy chain topology, and 120-ohm matching impedance is added at the beginning and the end. Each external CAN interface (electric) or CAN interface (optical) in the bus is equivalent to a CAN node for the reconfigurable CAN exchange box device. The CAN interface (electric) is composed of "CAN transceiver-isolator-CAN transceiver" circuit inside, and the two CAN communication interfaces are isolated from each other, solving the problem of non-common ground of multi-cabin equipment communication interface. The CAN interface (optical) is composed of "CAN transceiver-isolator-optoelectronic module" circuit inside, realizing signal isolation and long-distance transmission through optical signal transmission.

[0018] As shown in the figure, the reconfigurable CAN exchange box device internally adopts daisy chain topology, and 120-ohm matching impedance is added at the beginning and the end. Each external CAN interface (electric) or CAN interface (optical) in the bus is equivalent to a CAN node for the reconfigurable CAN exchange box device. The CAN interface (electric) is composed of "CAN transceiver-isolator-CAN transceiver" circuit inside, and the two CAN communication interfaces are isolated from each other, solving the problem of non-common ground of multi-cabin equipment communication interface. The CAN interface (optical) is composed of "CAN transceiver-isolator-optoelectronic module" circuit inside, realizing signal isolation and long-distance transmission through optical signal transmission. Figure 3 As shown in the figure, the reconfigurable CAN exchange box device internally adopts daisy chain topology, and 120-ohm matching impedance is added at the beginning and the end. Each external CAN interface (electric) or CAN interface (optical) in the bus is equivalent to a CAN node for the reconfigurable CAN exchange box device. The CAN interface (electric) is composed of "CAN transceiver-isolator-CAN transceiver" circuit inside, and the two CAN communication interfaces are isolated from each other, solving the problem of non-common ground of multi-cabin equipment communication interface. The CAN interface (optical) is composed of "CAN transceiver-isolator-optoelectronic module" circuit inside, realizing signal isolation and long-distance transmission through optical signal transmission.

[0019] Figure 4 ​​As shown, multiple reconfigurable CAN switch boxes are used in a network topology across multiple compartments. The reconfigurable CAN switch box located in the command compartment is configured as the master unit, monitoring bus data and interacting with the compartment's dispatching equipment via Ethernet, responding to control and query commands, and forwarding them within the CAN bus network. The reconfigurable CAN switch boxes located in the combat support and detection compartments are configured as slave units, possessing a monitoring mode, forming a CAN bus local area network within the compartment, connecting various devices within the compartment.

[0020] like Figure 5 As shown, based on the standard CAN bus protocol, a custom protocol frame for the reconfigurable CAN switch box device is formed using the CANID number in the arbitration area and the data frame area. This frame includes control frames, status frames, and heartbeat frames. The control frame has a fixed CANID bit of 0x100 and is issued by the reconfigurable CAN switch box device operating in master mode to distribute control commands. The status frame has a fixed CANID bit of 0x200, and the heartbeat frame has a fixed CANID bit of 0x300. These are used by the reconfigurable CAN switch box device to periodically send frames after monitoring the device status.

[0021] This invention is not limited to the specific embodiments described above, and various modifications and variations are possible. Any modifications, equivalent substitutions, or improvements made to the above embodiments based on the technical essence of this invention should be included within the scope of protection of this invention.

Claims

1. A reconfigurable CAN switch box device, characterized by: The MCU control circuit and the CAN bus are included; the MCU control circuit is the central part of data processing and control, realizes the analysis and processing of CAN bus data, external interaction and equipment control, the MCU control circuit is connected with the signal isolator, and then is hung on the CAN bus through the CAN transceiver; the master-slave identification circuit is connected with the MCU control circuit, realizes the identification of the master-slave mode of the CAN exchange box device; the combination circuit of "CAN transceiver-signal isolator-CAN transceiver" realizes the interface conversion of the CAN bus local area network in which the combination circuit is located; the combination circuit of "CAN transceiver-signal isolator-optoelectronic module" realizes the photoelectric conversion of the external interface; the combination circuit of "CAN transceiver-signal isolator-CAN transceiver" and the combination circuit of "CAN transceiver-signal isolator-optoelectronic module" are hung on the CAN bus; The CAN nodes of the multiple display and control console groups inside the cabin are converted into "single" nodes in the physical interface characteristics through "CAN transceiver-isolator-CAN transceiver" and "CAN transceiver-isolator-optoelectronic module", and are hung on the CAN bus inside the reconfigurable CAN exchange box device; for the cabin or the display and control console group which needs long-distance transmission, the long-distance transmission of data is realized through "CAN transceiver-isolator-optoelectronic module"; The reconfigurable CAN exchange box device has two working modes of master and slave, and the working mode of the reconfigurable CAN exchange box device in the master mode is switched through the code dial on the device; the built-in MCU of the reconfigurable CAN exchange box device in the master mode collects bus data, packages and transmits the data, and also can distribute control instructions in response to external instructions; the built-in MCU of the reconfigurable CAN exchange box device in the slave mode only completes the listening work on the bus; The internal CAN bus topology of a single reconfigurable CAN exchange box device is a daisy chain topology structure, and after the reconfigurable CAN exchange box device is used, the CAN nodes of the multiple display and control console groups inside the cabin form a local small CAN bus network after networking.

2. The reconfigurable CAN switch device of claim 1, wherein: The internal topology structure of the reconfigurable CAN exchange box adopts a daisy chain topology structure, each external electric or optical CAN interface in the bus is equivalent to a CAN node for the reconfigurable CAN exchange box device, and 120-ohm matching impedance is added at the head and tail.

3. The reconfigurable CAN switch device of claim 1, wherein: An 8-bit code dial switch is further included on the reconfigurable CAN exchange box device, and the master-slave working mode and the CAN ID number of the device are set through the code dial switch.

4. The reconfigurable CAN switch device of claim 3, wherein: The 1st to 7th bits of the code dial switch correspond to the CAN ID number of the device, and correspond to the CAN ID number range of 0x00 to 0x7F; the 8th bit of the code dial switch corresponds to the master-slave working mode of the device, is dialled to "ON" for the master working mode, is dialled to "OFF" for the slave working mode, the device is by default in the slave working mode, and the state of the code dial switch is identified during the initialization process after the device is powered on.

5. The reconfigurable CAN switch device of claim 1, wherein: The reconfigurable CAN switch box device in the master mode can interact with the scheduling device through Ethernet, respond to control instructions and query instructions, and forward in the CAN bus network while listening to bus data.

6. A reconfigurable CAN switch device according to any one of claims 1-5, characterized in that: On the basis of the CAN bus standard protocol, the reconfigurable CAN switch box device protocol frame is formed by using the CAN ID number and the data frame area, including a control frame, a state frame and a heartbeat frame. The control frame CAN ID fixed bit 0x100 is issued by the reconfigurable CAN switch box device working in the master mode, and is used for distributing control instructions; the state frame CAN ID fixed bit 0x200; and the heartbeat frame CAN ID fixed bit 0x300, which is used for the reconfigurable CAN switch box device to issue in a timing manner after listening to the device state.

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