CN119544454A

CN119544454A - A dual redundant CAN data storage device

Info

Publication number: CN119544454A
Application number: CN202411682608.7A
Authority: CN
Inventors: 陈润星; 李龙杰; 欧阳迪; 何鹏赓; 李中; 魏鑫; 于立明
Original assignee: China South Industries Group Automation Research Institute
Current assignee: China South Industries Group Automation Research Institute
Priority date: 2024-11-22
Filing date: 2024-11-22
Publication date: 2025-02-28

Abstract

The invention discloses a dual redundant CAN data storage device, which relates to the technical field of data transmission and can realize dual-channel CAN data acquisition, data storage and data reading. It solves the problems of data loss caused by the increase of CAN nodes, real-time storage of CAN data and rapid reading of stored data through the network. The device can effectively reduce the data loss rate and data node failure rate, and can realize real-time reminder of failure problems.

Description

Dual-redundancy CAN data storage device

Technical Field

The invention relates to the technical field of data transmission, in particular to a dual-redundancy CAN data storage device capable of reducing the data loss rate and the data node failure rate.

Background

The controller area network bus (CAN, control ler Area Network) is a serial communications protocol bus for real-time applications that CAN use twisted pair wires to transmit signals, one of the most widely used fieldbuses worldwide. The CAN protocol is used for communication between various components in an automobile to replace expensive and heavy wiring harnesses. The robustness of this protocol extends its use to other automation and industrial applications. The features of the CAN protocol include serial data communication for integrity, providing real-time support, transmission rates up to 1Mb/s, and 11-bit addressing and error detection capabilities.

However, with the increase of the data nodes of the CAN bus, the problem that the failure rate of the nodes and the data loss rate are high due to the overlarge data pressure of the CAN bus CAN be caused, and the failure time CAN not be recorded in time and the stored data CAN not be read quickly.

Disclosure of Invention

In view of the above, the present invention provides a dual redundancy CAN data storage device for overcoming or at least partially solving the above problems. The problem of CAN data real-time storage and the problem of fast reading of stored data through a network caused by the increase of CAN nodes is solved.

The invention provides the following scheme:

A dual redundancy CAN data storage device comprising:

the system comprises a processor, a first CAN communication module, a second CAN communication module, a storage module and a network communication module, wherein the processor is connected with the first CAN communication module, the second CAN communication module, the storage module and the network communication module;

the processor is configured with FreeRTOS real-time operating system, and the processor is used for performing the following operations:

querying the number of the data nodes on the CAN bus through a handshake instruction frame;

sequentially transmitting a device transmission frame to the data nodes responding to the handshake instruction frame;

Determining a target data node according to the response condition of the equipment transmission frame, wherein the target data node is the data node which sends an equipment state frame after receiving the equipment transmission frame;

receiving node data to be stored sent by the target data node through one or both of the first CAN communication module and the second CAN communication module;

Converting the node data to be stored into a target expansion frame format and then storing the target expansion frame format in the storage module;

receiving a data reading instruction sent by the data equipment to be read through the Ethernet through the network communication module;

after the read instruction is determined to be legal, the data to be stored corresponding to the read instruction is sent to the data equipment to be read through the Ethernet.

Preferably the storage module is configured with a log file for recording system errors to record all errors that occur.

Preferably, the processor is also connected with a plurality of indicator lights, and the processor is also used for executing the following operations:

when determining that the type II I low-risk error occurs, controlling a yellow indicator lamp to be always on;

When the I I types of stroke danger errors are determined, the orange indicator lamp is controlled to flash;

When the type I high risk error is determined, the red indicator light is controlled to continuously flash until the operator is out of order and the system is powered up again.

Preferably, the processor is further connected with a serial port debugging module, the serial port debugging module is used for outputting the system errors, and the serial port debugging module comprises a GLb2582C transceiver.

Preferably, the storage module uses a file management system FATFS for data storage.

Preferably, the equipment transmission frame corresponding to the target ID is retransmitted if the equipment status frame is not received after the equipment transmission frame is transmitted, and the node data is skipped if the equipment status frame is not received for more than 3 times.

Preferably, the target extended frame format comprises a type of an RTR representation frame, wherein RTR=0 is represented as a data frame, RTR=1 is represented as a remote frame, DLC represents the actual length of the data frame, the ID of the extended format has 29 bits, the range of the frame ID is 0000 0000-1FFF FFFF, the forbidden high 7 bits are all hidden, the extended ID of the CAN is reassigned, ID [28:21] is used as the CAN frame type, ID [20:18] is used as the CAN priority, ID [17:16] is used as the standby, ID [15:8] is used as the target address of the CAN frame, and ID [7:0] is used as the source address of the CAN frame.

Preferably, the processor includes a HWD32F429 chip packaged with 144pin LQFP.

Preferably, the first CAN communication module and the second CAN communication module both comprise an SGM4553 electronic dual-channel non-inverting bidirectional level converter and a JM3062W isolated control region physical layer transceiver, and the storage module comprises an SM25QH256M nonvolatile serial Flash memory chip.

Preferably, the processor is further connected with a temperature detection module, and the temperature detection module comprises an NST175 digital temperature sensor.

According to the specific embodiment provided by the invention, the invention discloses the following technical effects:

The dual-redundancy CAN data storage device provided by the embodiment of the application CAN realize dual-path CAN data acquisition, data storage and data reading. The problem of CAN data real-time storage and the problem of fast reading of stored data through a network caused by the increase of CAN nodes is solved. The device can effectively reduce the data loss rate and the data node failure rate, and can realize real-time reminding of the failure problem.

Of course, it is not necessary for any one product to practice the invention to achieve all of the advantages set forth above at the same time.

Drawings

In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings that are required to be used in the embodiments will be briefly described below. It is evident that the drawings in the following description are only some embodiments of the present invention and that other drawings may be obtained from these drawings by those of ordinary skill in the art without inventive effort.

FIG. 1 is a connection block diagram of a dual redundancy CAN data storage device provided by an embodiment of the invention;

FIG. 2 is a schematic diagram of a dual redundancy CAN data storage device using state connection according to an embodiment of the invention;

FIG. 3 is a schematic diagram of a CAN communication module of one path provided by the embodiment of the invention;

FIG. 4 is a schematic diagram of a memory module according to an embodiment of the present invention;

FIG. 5 is a schematic diagram of a temperature detection module according to an embodiment of the present invention;

FIG. 6 is a schematic diagram of a serial port debug module according to an embodiment of the present invention;

Fig. 7 is a schematic diagram of an ethernet communication module according to an embodiment of the present invention;

fig. 8 is a schematic diagram of an ethernet communication module according to an embodiment of the present invention;

FIG. 9 is a schematic diagram of a software implementation provided by an embodiment of the present invention;

FIG. 10 is a schematic diagram of an extended frame data format provided by an embodiment of the present invention;

FIG. 11 is a diagram illustrating redefinition of an extended ID provided by an embodiment of the present invention;

Fig. 12 is a schematic diagram of a data acquisition process according to an embodiment of the present invention.

Detailed Description

The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention. It will be apparent that the described embodiments are only some, but not all, embodiments of the invention. All other embodiments, which are derived by a person skilled in the art based on the embodiments of the invention, fall within the scope of protection of the invention.

Referring to fig. 1, a dual redundancy CAN data storage device provided in an embodiment of the present invention, as shown in fig. 1, may include:

the embodiment of the application can provide the method for retransmitting the equipment transmission frame corresponding to the target ID if the equipment state frame is not received after the equipment transmission frame is transmitted, and skip the node data if the equipment state frame is not received for more than 3 times.

In a specific implementation, the embodiment of the application can provide that the target expansion frame format comprises a type of RTR representing frame, RTR=0 represents a data frame, and RTR=1 represents a remote frame. DLC represents the actual length of a data frame, the ID of an extended format has 29 bits, the range of the frame ID is 0000 0000-1FFF FFFF, the forbidden high 7 bits are all recessive, the extended ID of the CAN is reassigned, ID [28:21] is used as the type of the CAN frame, ID [20:18] is used as the CAN priority, ID [17:16] is used as the standby, ID [15:8] is used as the target address of the CAN frame, and ID [7:0] is used as the source address of the CAN frame.

In order to record the error information, the embodiment of the application can also provide that the storage module is configured with a log file for recording the system error so as to record all the occurred errors.

In order to realize timely notifying the user when an error occurs, the embodiment of the application can also provide that the processor is also connected with a plurality of indicator lamps, and the processor is also used for executing the following operations:

when the low-risk error of class III is determined, controlling a yellow indicator lamp to be always on;

when the risk error in class II is determined, the orange indicator lamp is controlled to flash;

In order to facilitate error information output, the embodiment of the application can also provide that the processor is also connected with a serial port debugging module, wherein the serial port debugging module is used for outputting the system errors and comprises a GLb2582C transceiver.

Further, the storage module uses a file management system FATFS to store data.

The processor includes a HWD32F429 chip packaged with 144pin LQFP. The first CAN communication module and the second CAN communication module both comprise an SGM4553 electronic dual-channel non-inverting bidirectional level converter and a JM3062W isolated control area physical layer transceiver, and the storage module comprises an SM25QH256M nonvolatile serial Flash memory chip. The processor is also connected with a temperature detection module, and the temperature detection module comprises an NST175 digital temperature sensor.

The dual-redundancy CAN data storage device provided by the embodiment of the application aims at the aspects of industrial control and industrial automation of a CAN bus. The device adopts a domestic chip HWD32F429 as a core processor, mainly externally comprises a CAN bus interface chip JM3062W, an SPI FLASH memory chip SM25QH256M, a temperature sensor NST175, a network module and a serial port transceiver GLb2582C, and is adaptive to a FreeRTOS real-time operating system as a software platform of a data acquisition device to finish CAN bus data receiving and transmitting processing and storage, prompts and early warns errors generated in an operating system through an indicator lamp, reduces node failure rate and node data loss rate caused by increasing data nodes through roll-call software design, adds a file management system FATFS to carry out data management in the design, and realizes a quick reading function of stored data network communication by utilizing a third party LwIP network protocol stack.

The hardware and software implementation method of the device provided by the embodiment of the application is described in detail below.

The embodiment of the application provides a dual-redundancy CAN data storage device which adopts HWD32F429 of Chengdu microelectronic technology Co. The MCU is based on-M432-bi RISC CPU supporting up to 240MHz operating frequency, wide voltage range of 1.8 v-3.6 v and wide temperature range of-40 ℃ to 105 ℃, the peripherals are rich, including 22 serial communication interfaces (I2C/UART), 2-way CAN, 3 independent 12bi t 2.5MSPS ADC, etc., HWD32F429 series provides LQFP package of 144pin, 176pin, TFBGA package of 208pin for high performance frequency conversion control, digital power, intelligent hardware, ioT connection module, etc. The present application employs an LQFP package HWD32F429 employing 144 pins. The module architecture design of the dual redundancy CAN data storage device is as shown in fig. 1.

The CAN data storage device is connected into two paths of CAN buses to receive CAN protocol data transmitted from an external system, and two paths of data receiving channels are redundant, and the connection diagram is shown in figure 2. The CAN data acquisition device CAN filter data on the CAN bus according to the CAN filter, and data meeting the requirements is selected for receiving.

The CAN communication module employs an SGM4553 electronic dual channel non-inverting bi-directional level shifter and a JM3062W isolated Control Area (CAN) physical layer transceiver. SGM4553 has two independent configurable power rails, the A port supports 1.65V to 5.5V operating voltage while tracking VA power, the B port supports 2.3V to 5.5V operating voltage while tracking VB power, supports lower and higher logic signal levels, and does not require directional control signals, simplifying circuit design and saving cost. JM3062W creates a completely isolated interface between CAN protocol controller and physical layer bus, and provides differential receiving and differential transmitting capability, signal transmission rate CAN reach 1Mbps, and CAN isolate noise and interference and prevent damage to sensitive circuit by matching with internal integrated isolated DC-DC. The schematic diagram of one CAN communication module is shown in figure 3.

The storage module selects an SM25QH256M nonvolatile serial Flash memory chip, the working voltage of the storage chip is 2.7V-3.6V, instructions, addresses and data are serially input into the chip through a clock, and then the chip is operated according to the instruction requirements after being processed by internal control logic. The schematic diagram of the memory module is shown in fig. 4.

The temperature detection module adopts NST175, NST175 is a digital temperature sensor with low power consumption and high precision, does not need to be calibrated, is highly linear, does not need to be calculated or look-up table to deduce temperature, has the working temperature range of-55 ℃ to 125 ℃, has the resolution of 0.0625 ℃, and is suitable for on-board and off-board application in industrial and consumer markets. The temperature detection module is shown in fig. 5.

And the serial port debugging module adopts a GLb2582C transceiver to realize isolation and level conversion of serial port signals. The schematic diagram of the serial port debugging module is shown in fig. 6.

And the network communication module is provided with an Ethernet communication interface serving as an interface for reading data by the upper computer. The interface is arranged on the front panel, so that the connection of operators is facilitated. The ethernet communication module design is shown in fig. 7.

The HWD32F429 is self-contained with MAC functionality and provides MII interfaces. The PHY chip adopts an EM971AP type chip. The EM971AP is an Ethernet physical transceiver circuit supporting 10/100Mb, integrates an Ethernet PHY, supports 10BASE-T and 100BASE-TX, supports an MII interface and can replace an LXT971A chip. The network transformer adopts LT1306-A to realize the external 10/100Mbps self-adaptive Ethernet communication function, and the design of the Ethernet communication schematic diagram is shown in figure 8.

As shown in FIG. 9, the software portion mainly completes tasks of a data receiving task, a data storing task, a data reading task and an error processing task. The task modules utilize FreeRTOS's multitasking parallel processing technique to achieve synchronous collaboration with each other through a message and semaphore synchronization mechanism.

Redefining CAN frame data, standard CAN data frames generally include a frame start, an arbitration section, a control section, a data section, a CRC section, an ACK section, and a frame end, and the embodiment of the present application employs an extended frame format as shown in fig. 10.

RTR represents the type of frame, rtr=0 represents a data frame, and rtr=1 represents a remote frame. DLC represents the actual length of a data frame. The extended format ID has 29 bits, the frame ID range is 0000 0000-1FFF FFFF, and the forbidden high 7 bits are all recessive. Reassigning the extended ID of the CAN, taking the ID [28:21] as the type of the CAN frame, taking the ID [20:18] as the priority of the CAN, taking the ID [17:16] as the standby, taking the ID [15:8] as the target address of the CAN frame and taking the ID [7:0] as the source address of the CAN frame. The extension ID redefined as in fig. 11.

In the data collection process, as shown in fig. 12, before collecting the device state data, the device inquires the number of data nodes on the CAN bus through a handshake instruction frame. The CAN data acquisition device supports the acquisition of 30 data nodes. The apparatus then transmits a device transport frame to the data node in response to the handshake instruction frame in turn. The data node receiving the device transmission frame will immediately send the device status frame. If the CAN data acquisition device does not receive the equipment state frame after transmitting the equipment transmission frame, the equipment transmission frame corresponding to the target ID is retransmitted. If the device status frame is not received for more than 3 times, the node data is skipped and the next device transmission frame is sent.

The kernel of FreeRTOS has no file system for data storage and reading, and in order to simplify the programming flow and improve the development efficiency, a file management system FATFS which is efficient, low in resource occupancy rate and specially designed for a small embedded system is added in the design.

Another key function of data storage is to ensure that the data stored in FLASH can be read out quickly and accurately. In the case of mass storage, fast searching and timely returning of a certain file are of great significance to the use experience of operators. The data recording system of the application adopts Ethernet as a transmission path for data reading. And the network communication function is realized by using a third party LwIP network protocol stack. When a data reading instruction from the Ethernet is received, firstly checking the validity of the instruction, and if the query instruction is legal, sending a network query data receiving success message to the task management process.

And (3) performing error processing, namely establishing a log file special for recording system errors in a chip of the storage module so as to record all the occurred errors. When a low risk type ii error occurs, the yellow indicator light should be normally on, when a medium risk type I I error occurs, the orange indicator light should flash, when a high risk type I error occurs, the red indicator light should flash all the time until the operator is out of order and the system is powered up again. The risk error can be output in real time through the debugging serial port, and the error type is convenient for an operator to remove faults.

In a word, the dual-redundancy CAN data storage device provided by the application CAN realize dual-path CAN data acquisition, data storage and data reading. The problem of CAN data real-time storage and the problem of fast reading of stored data through a network caused by the increase of CAN nodes is solved. The device can effectively reduce the data loss rate and the data node failure rate, and can realize real-time reminding of the failure problem.

It is noted that in the present application, relational terms such as first and second, and the like are used solely to distinguish one entity or action from another entity or action without necessarily requiring or implying any actual such relationship or order between such entities or actions. Moreover, the terms "comprises," "comprising," or any other variation thereof, are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements does not include only those elements but may include other elements not expressly listed or inherent to such process, method, article, or apparatus. Without further limitation, an element defined by the phrase "comprising one does not exclude the presence of other like elements in a process, method, article, or apparatus that comprises an element.

From the above description of embodiments, it will be apparent to those skilled in the art that the present application may be implemented in software plus a necessary general hardware platform. Based on such understanding, the technical solution of the present application may be embodied essentially or in a part contributing to the prior art in the form of a software product, which may be stored in a storage medium, such as a ROM/RAM, a magnetic disk, an optical disk, etc., including several instructions for causing a computer device (which may be a personal computer, a server, or a network device, etc.) to execute the method described in the embodiments or some parts of the embodiments of the present application.

In this specification, each embodiment is described in a progressive manner, and identical and similar parts of each embodiment are all referred to each other, and each embodiment mainly describes differences from other embodiments. In particular, for a system or system embodiment, since it is substantially similar to a method embodiment, the description is relatively simple, with reference to the description of the method embodiment being made in part. The systems and system embodiments described above are merely illustrative, wherein the elements illustrated as separate elements may or may not be physically separate, and the elements shown as elements may or may not be physical elements, may be located in one place, or may be distributed over a plurality of network elements. Some or all of the modules may be selected according to actual needs to achieve the purpose of the solution of this embodiment. Those of ordinary skill in the art will understand and implement the present invention without undue burden.

The foregoing description is only of the preferred embodiments of the present invention and is not intended to limit the scope of the present invention. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention are included in the protection scope of the present invention.

Claims

1. The dual-redundancy CAN data storage device is characterized by comprising a processor, wherein the processor is connected with a first CAN communication module, a second CAN communication module, a storage module and a network communication module, the first CAN communication module is used for being connected with a first CAN bus, the second CAN communication module is used for being connected with a second CAN bus, the first CAN bus and the second CAN bus are respectively connected with a plurality of data nodes, and the network communication module is used for realizing network communication with data equipment to be read by utilizing a third party LwIP network protocol stack;

2. The dual redundant CAN data storage device of claim 1 wherein the storage module is configured with a log file for recording system errors to record all errors that occur.

3. The dual redundant CAN data storage device of claim 2 wherein the processor is further coupled with a plurality of indicator lights, the processor further configured to:

4. The dual redundancy CAN data storage device of claim 2, wherein the processor is further coupled to a serial port debug module, wherein the serial port debug module is configured to output the system error, and wherein the serial port debug module comprises a GLb2582C transceiver.

5. The dual redundant CAN data storage device of claim 1, wherein the storage module employs a file management system FATFS for data storage.

6. The dual redundancy CAN data storage apparatus of claim 1, wherein the device status frame is not received after the device status frame is transmitted, wherein the device status frame corresponding to the destination ID is retransmitted, and wherein the node data is skipped if the device status frame is not received more than 3 times.

7. The dual redundancy CAN data storage apparatus of claim 1, wherein the target extended frame format comprises RTR representing a frame type, rtr=0 representing a data frame, rtr=1 representing a remote frame, DLC representing an actual length of the data frame, the extended format having an ID of 29 bits, the frame ID ranging from 0000 0000-1FFF FFFF, the upper 7 prohibited bits being implicit, the extended ID of CAN reassigned, ID [28:21] as a CAN frame type, ID [20:18] as CAN priority, ID [17:16] as a spare, ID [15:8] as a target address of the CAN frame, and ID [7:0] as a source address of the CAN frame.

8. The dual redundant CAN data storage device of claim 1, wherein the processor comprises an LQFP packaged HWD32F429 chip using 144 pins.

9. The dual-redundancy CAN data storage apparatus of claim 1, wherein the first CAN communication module and the second CAN communication module each comprise an SGM4553 electronic dual channel non-inverting bi-directional level shifter and a JM3062W isolated control area physical layer transceiver, and wherein the storage module comprises an SM25QH256M non-volatile serial Flash memory chip.

10. The dual redundant CAN data storage device of claim 1 wherein the processor is further coupled with a temperature detection module comprising an NST175 digital temperature sensor.