A CAN Wake-up Source Identification System and Method

Abstract

The present application discloses a CAN wake-up source identification system and method, including: a first CAN chip, a second CAN chip, a first wake-up circuit, a second wake-up circuit, a system base chip SBC, and an MCU; the first CAN chip and the second CAN chip can receive wake-up instructions or voltage signals on the CAN bus, generate a first wake-up signal and a second wake-up signal respectively, and send the wake-up signals to the SBC. The SBC realizes the wake-up function and outputs a voltage signal to the MCU, the first CAN chip, and the second CAN chip. The first wake-up circuit processes the first wake-up signal to obtain a third wake-up signal and sends it to the MCU; the second wake-up circuit processes the second wake-up signal to obtain a fourth wake-up signal and sends it to the MCU. When the MCU receives the voltage signal to power on, it can identify the wake-up source based on the received wake-up signals, that is, when multiple CAN chips send wake-up signals to the MCU, the MCU can only receive one kind of wake-up signal, and identify the CAN chip of the wake-up system according to the received wake-up signal.

Description

Technical Field

[0001] This application relates to the field of electronic technologies, and in particular, to a CAN wake-up source identification system and method. Background Art

[0002] With the wide application of electric vehicles, they have gradually become very convenient means of transportation in people's daily lives. As an important part of electric vehicles, the Battery Management System (BMS) is mainly used for intelligent management and maintenance of each battery unit, preventing the battery from overcharging and over-discharging, extending the service life of the battery, and monitoring the battery status.

[0003] When the whole vehicle is not started or not in a driving state, in order to reduce the working energy consumption of the BMS itself, the BMS will be controlled to enter the sleep state. When the whole vehicle is normally started and driving, the BMS can be woken up by using the CAN bus, that is, when the CAN chip receives the wake-up frame sent by the CAN bus, it can output a voltage signal to the System Basis Chip (SBC) of the BMS. Generally speaking, the SBC is an independent chip that includes features such as power supply, communication, monitoring and diagnosis, and GPIO. When the SBC is woken up, it can output power to the MCU and other circuit parts, so that the MCU can identify the wake-up source according to the working state of the CAN chip. When there are multiple CAN chips in the BMS, after the SBC outputs power, other CAN chips that have not received the wake-up frame are also powered on at this time and can also output voltage signals to the SBC. At this time, the MCU cannot identify the CAN chip that wakes up the BMS. Summary of the Invention

[0004] In view of this, the embodiments of this application provide a CAN wake-up source identification system and method, so that the MCU can identify the CAN chip that wakes up the system.

[0005] In a first aspect, the embodiments of this application provide a CAN wake-up source identification system, and the system includes: a first CAN chip, a second CAN chip, a first wake-up circuit, a second wake-up circuit, a system basis chip SBC, and a micro control unit MCU;

[0006] The first CAN chip is configured to receive a wake-up instruction or voltage signal of the CAN bus, generate a first wake-up signal, and send the first wake-up signal to the SBC;

[0007] The second CAN chip is configured to receive a wake-up instruction or voltage signal of the CAN bus, generate a second wake-up signal, and send the second wake-up signal to the SBC;

[0008] The first wake-up circuit is configured to process the first wake-up signal to obtain a third wake-up signal, and send the third wake-up signal to the MCU;

[0009] The second wake-up circuit is configured to process the second wake-up signal to obtain a fourth wake-up signal, and send the fourth wake-up signal to the MCU. The first wake-up circuit is connected to the second wake-up circuit, and both the first wake-up circuit and the second wake-up circuit have a priority arbitration function;

[0010] The SBC is configured to implement a wake-up function according to the first wake-up signal or the second wake-up signal, and output the voltage signal to the MCU, the first CAN chip, and the second CAN chip;

[0011] The MCU is configured to receive the voltage signal to power on, and identify the wake-up source based on the received wake-up signal, where the wake-up signal is the third wake-up signal or the fourth wake-up signal.

[0012] In a possible implementation, the first wake-up circuit includes: a first voltage conversion circuit and a first priority arbitration circuit;

[0013] The first voltage conversion circuit is configured to convert the first wake-up signal into a first trigger signal, and send the first trigger signal to the first priority arbitration circuit;

[0014] The first priority arbitration circuit is configured to receive the first trigger signal and generate the third wake-up signal.

[0015] In a possible implementation, the second wake-up circuit includes: a second voltage conversion circuit and a second priority arbitration circuit;

[0016] The second voltage conversion circuit is configured to convert the second wake-up signal into a second trigger signal, and send the second trigger signal to the second priority arbitration circuit;

[0017] The second priority arbitration circuit is configured to receive the second trigger signal and generate the fourth wake-up signal.

[0018] In a possible implementation, the first priority arbitration circuit includes: a first edge D flip-flop and a first NOR gate;

[0019] The second priority arbitration circuit includes: a second edge D flip-flop and a second NOR gate.

[0020] In a possible implementation, the output terminal of the first NOR gate is connected to the input terminal of the second edge D flip-flop.

[0021] In a second aspect, an embodiment of the present application provides a method for identifying a CAN wake-up source. The method is applied to a CAN wake-up source identification system, which includes: a first CAN chip, a second CAN chip, a first wake-up circuit, a second wake-up circuit, an SBC, and an MCU. The method includes:

[0022] The first CAN chip receives a wake-up instruction on the CAN bus and generates a first wake-up signal;

[0023] The SBC realizes the wake-up function according to the first wake-up signal and outputs a voltage signal to the MCU, the first CAN chip, and the second CAN chip;

[0024] The first wake-up circuit converts the first wake-up signal into a third wake-up signal and sends the third wake-up signal to the MCU;

[0025] The second CAN chip generates a second wake-up signal according to the voltage signal;

[0026] The first wake-up circuit shields the function of the second wake-up circuit;

[0027] The MCU receives the voltage signal to power on and identifies the wake-up source based on the received third wake-up signal.

[0028] In a possible implementation, the method further includes:

[0029] The MCU controls the first CAN chip and the second CAN chip to enter the sleep state and sends a CLEAR signal to clear the third wake-up signal in the first wake-up circuit.

[0030] In a third aspect, an embodiment of the present application provides a method for identifying a CAN wake-up source. The method is applied to a CAN wake-up source identification system, which includes: a first CAN chip, a second CAN chip, a first wake-up circuit, a second wake-up circuit, an SBC, and an MCU. The method includes:

[0031] The second CAN chip receives a wake-up instruction on the CAN bus and generates a fifth wake-up signal;

[0032] The SBC realizes the wake-up function according to the fifth wake-up signal and outputs a voltage signal to the MCU, the first CAN chip, and the second CAN chip;

[0033] The second wake-up circuit converts the fifth wake-up signal into a sixth wake-up signal and sends the sixth wake-up signal to the MCU;

[0034] The first CAN chip generates a seventh wake-up signal according to the voltage signal;

[0035] The second wake-up circuit shields the function of the first wake-up circuit;

[0036] The MCU receives the voltage signal to power on and identifies the wake-up source based on the received sixth wake-up signal.

[0037] In a fourth aspect, an embodiment of the present application provides a device for identifying a CAN wake-up source, the device comprising: a memory and a processor;

[0038] The memory is used to store relevant program codes;

[0039] The processor is used to call the program codes to execute the method for identifying a CAN wake-up source according to any implementation manner of the second aspect or the third aspect.

[0040] In a fifth aspect, an embodiment of the present application provides a computer-readable storage medium, which is used to store a computer program, and the computer program is used to execute the method for identifying a CAN wake-up source according to any implementation manner of the second aspect or the third aspect.

[0041] Thus, the embodiments of the present application have the following beneficial effects:

[0042] In the above implementation manners of the present application, a CAN wake-up source identification system is provided. The system includes: a first CAN chip, a second CAN chip, a first wake-up circuit, a second wake-up circuit, a system base chip SBC, and a micro-control unit MCU. The first CAN chip and the second CAN chip can receive wake-up instructions or voltage signals on the CAN bus, generate a first wake-up signal and a second wake-up signal respectively, and send the wake-up signals to the SBC. The SBC is used to implement the wake-up function according to the first wake-up signal or the second wake-up signal, and output a voltage signal to the MCU, the first CAN chip, and the second CAN chip. The first wake-up circuit can process the first wake-up signal to obtain a third wake-up signal, and send the third wake-up signal to the MCU. The second wake-up circuit can be used to process the second wake-up signal to obtain a fourth wake-up signal, send the fourth wake-up signal to the MCU, and the first wake-up circuit is connected to the second wake-up circuit. The first wake-up circuit and the second wake-up circuit have a priority function. For example, when the first wake-up circuit first sends the third wake-up signal to the MCU, the function of the second wake-up circuit can be blocked, and the second wake-up circuit cannot generate a wake-up signal for the MCU. When the MCU receives the voltage signal sent by the SBC to power on, it can identify the wake-up source based on the received wake-up signal, where the wake-up signal is the third wake-up signal or the fourth wake-up signal. That is, through the CAN wake-up source identification system provided by the embodiments of the present application, when multiple CAN chips send wake-up signals to the MCU, the MCU can only receive one wake-up signal, so that the CAN chip of the wake-up system can be identified according to the received wake-up signal. BRIEF DESCRIPTION OF THE DRAWINGS

[0043] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the following will briefly introduce the drawings required for the description of the embodiments. Obviously, the drawings in the following description are only some embodiments provided in the present application, and those of ordinary skill in the art can also obtain other drawings based on these drawings.

[0044] Figure 1 Schematic diagram of a CAN wake-up source identification system provided by an embodiment of the present application;

[0045] Figure 2 Schematic diagram of an edge D flip-flop provided by an embodiment of the present application;

[0046] Figure 3 Schematic diagram of the input signal and output signal of an edge D flip-flop provided by an embodiment of the present application;

[0047] Figure 4 Schematic diagram of another CAN wake-up source identification system provided by an embodiment of the present application;

[0048] Figure 5aSchematic diagram of signal changes when the first CAN chip wakes up the system;

[0049] Figure 5b Schematic diagram of signal changes when the system is in sleep mode;

[0050] Figure 6 Schematic diagram of the principle of a method for identifying a CAN wake-up source provided by an embodiment of the present application;

[0051] Figure 7 Schematic diagram of the principle of another method for identifying a CAN wake-up source provided by an embodiment of the present application;

[0052] Figure 8 Schematic diagram of a device for identifying a CAN wake-up source provided by the present application. Detailed implementation manners

[0053] Next, the technical solutions in the embodiments of the present application will be clearly and completely described in conjunction with the accompanying drawings in the embodiments of the present application. The described embodiments are only exemplary embodiments of the present application and not all implementation manners. Those skilled in the art can obtain other embodiments without creative efforts in combination with the embodiments of the present application, and these embodiments are also within the protection scope of the present application.

[0054] When the vehicle is not started or not in a driving state, in order to reduce the working power consumption of the BMS system itself, the BMS will be controlled to enter the sleep state. When the vehicle is normally started and driving, the BMS can be woken up by using the CAN bus, that is, when the CAN chip receives the wake-up frame sent by the CAN bus, it can output a voltage signal to the system base chip SBC of the BMS. The SBC is an independent chip that includes characteristics such as power supply, communication, monitoring and diagnosis, and GPIO. When the SBC is woken up after receiving the voltage signal, it can output a power signal to the MCU and other circuit parts, so that the MCU can identify the wake-up source according to the working state of the CAN chip after being powered on. However, when there are multiple CAN chips in the BMS, after the SBC outputs power, other CAN chips that have not received the wake-up frame are also powered on at this time and can also output voltage signals. At this time, the MCU cannot identify the CAN chip that wakes up the BMS.

[0055] Based on this, the embodiment of the present application provides a CAN wake-up source identification system so that the MCU can identify the CAN chip that wakes up the system. Specifically, the system includes: a first CAN chip, a second CAN chip, a first wake-up circuit, a second wake-up circuit, a system basic chip SBC and a microcontroller unit MCU. The first CAN chip and the second CAN chip can receive the wake-up instruction or voltage signal of the CAN bus, generate a first wake-up signal and a second wake-up signal respectively, and send the generated wake-up signal to the SBC, which is used to implement the wake-up function according to the first wake-up signal or the second wake-up signal, and output the voltage signal to the MCU, the first CAN chip and the second CAN chip. The first wake-up circuit can process the first wake-up signal to obtain a third wake-up signal, and send the third wake-up signal to the MCU; the second wake-up circuit can be used to process the second wake-up signal to obtain a fourth wake-up signal, and send the fourth wake-up signal to the MCU, and the first wake-up circuit is connected to the second wake-up circuit. The first wake-up circuit and the second wake-up circuit have a quick answer function. For example, when the first wake-up circuit first sends the third wake-up signal to the MCU, the function of the second wake-up circuit can be shielded, and the second wake-up circuit cannot generate a wake-up signal to the MCU. When the MCU receives the voltage signal sent by the SBC to power on, the wake-up source can be identified based on the received wake-up signal, where the wake-up signal is the third wake-up signal or the fourth wake-up signal. That is, through the CAN wake-up source identification system provided by the embodiment of the present application, when multiple CAN chips send wake-up signals to the MCU, the MCU can only receive one wake-up signal, so that the CAN chip that wakes up the system can be identified based on the received wake-up signal.

[0056] The working principle of a CAN wake-up source identification system provided by the present application will be introduced below in conjunction with the accompanying drawings.

[0057] See also Figure 1 , Figure 1 A schematic diagram of a CAN wake-up source identification system provided in an embodiment of the present application.

[0058] In this embodiment, a system including two chips is used as an example for description. The system includes a first CAN chip 101, a second CAN chip 102, a first wake-up circuit 103, a second wake-up circuit 104, a system basic chip SBC 105, and a micro control unit MCU 106;

[0059] The first CAN chip 101 is used to receive a wake-up instruction or a voltage signal of the CAN bus, generate a first wake-up signal, and send the first wake-up signal to the SBC 105;

[0060] The second CAN chip 102 is used to receive a wake-up instruction or voltage signal of the CAN bus, generate a second wake-up signal, and send the second wake-up signal to the SBC 105;

[0061] The first wake-up circuit 103 is used to process the first wake-up signal to obtain a third wake-up signal and send the third wake-up signal to the MCU 106;

[0062] The second wake-up circuit 104 is used to process the second wake-up signal to obtain a fourth wake-up signal and send the fourth wake-up signal to the MCU 106. Moreover, the first wake-up circuit 103 is connected to the second wake-up circuit 104, and both the first wake-up circuit 103 and the second wake-up circuit 104 have a priority function;

[0063] The SBC 105 is used to implement the wake-up function according to the first wake-up signal or the second wake-up signal and output a voltage signal to the MCU 106, the first CAN chip 101, and the second CAN chip 102;

[0064] The MCU 106 is used to receive the voltage signal to power on and identify the wake-up source based on the received wake-up signal, and the wake-up signal is the third wake-up signal or the fourth wake-up signal.

[0065] In practical applications, after the BMS system enters the sleep state, the CAN chip of the BMS system can receive the wake-up frame of the CAN bus to wake up the entire BMS system. Specifically, in a possible way, when the first CAN chip receives the wake-up instruction of the CAN bus, it generates a first wake-up signal according to the wake-up instruction and sends the first wake-up signal to the SBC. The SBC can implement the wake-up function according to the first wake-up signal and output a voltage signal. The first wake-up circuit can receive the first wake-up signal generated by the first CAN chip, process the first wake-up signal to obtain a third wake-up signal, and then send the third wake-up signal to the MCU. After the SBC implements the wake-up function, it can output a voltage signal to the MCU, the first CAN chip, the second CAN chip, and other circuit parts, and the MCU completes power-on. At this time, if the second CAN chip does not receive the wake-up instruction, but the second CAN chip can also power on according to the voltage signal sent by the SBC and output a second wake-up signal. Since the first wake-up circuit is connected to the second wake-up circuit and the first wake-up circuit has a priority function, after the first wake-up circuit generates the third wake-up signal, it can block the function of the second wake-up circuit, that is, the second wake-up circuit cannot convert the second wake-up signal into a fourth wake-up signal and send it to the MCU. Therefore, the MCU only receives the third wake-up signal sent by the first wake-up circuit. Therefore, the MCU can identify the CAN chip that wakes up the system as the first CAN chip according to the third wake-up signal.

[0066] Similarly, when the second CAN chip first receives a wake-up instruction from the CAN bus, it can generate a second wake-up signal and send the second wake-up signal to the SBC. The SBC can implement the wake-up function based on the second wake-up signal and output a voltage signal. The second wake-up circuit can receive the second wake-up signal generated by the second CAN chip, process the second wake-up signal to obtain a fourth wake-up signal, and then send the fourth wake-up signal to the MCU. When the SBC implements the wake-up function, it can output a voltage signal to the MCU, the first CAN chip, the second CAN chip, and other circuit parts, and the MCU is powered on. At this time, if the first CAN chip does not receive a wake-up instruction, but the first CAN chip can also be powered on according to the voltage signal sent by the SBC and output a first wake-up signal. Since the first wake-up circuit and the second wake-up circuit are connected, and the second wake-up circuit has a priority function, after the second wake-up circuit generates a fourth wake-up signal, it can block the function of the first wake-up circuit, that is, the first wake-up circuit cannot convert the first wake-up signal into a third wake-up signal and send it to the MCU. Therefore, the MCU only receives the fourth wake-up signal sent by the second wake-up circuit. Therefore, the MCU can identify the CAN chip of the wake-up system as the second CAN chip according to the fourth wake-up signal.

[0067] In the CAN wake-up source identification system provided by the embodiments of the present application, when multiple CAN chips send wake-up signals to the MCU, the wake-up circuit with a priority function in the system can be used to send a wake-up signal to the MCU, so that the MCU can identify the CAN chip of the wake-up system according to the received wake-up signal.

[0068] In a possible implementation manner, the first wake-up circuit includes a first voltage conversion circuit and a first priority circuit. Among them, the first voltage conversion circuit can convert the first wake-up signal into a first trigger signal and then send the first trigger signal to the first priority circuit. The first priority circuit can generate a third wake-up signal according to the received first trigger signal and then send the third wake-up signal to the MCU.

[0069] Similarly, the second wake-up circuit can also be composed of a second voltage conversion circuit and a second priority circuit. Among them, the second voltage conversion circuit can convert the second wake-up signal into a second trigger signal and then send the second trigger signal to the second priority circuit. The second priority circuit can generate a fourth wake-up signal according to the received second trigger signal and then send the fourth wake-up signal to the MCU.

[0070] In a possible implementation, the first rush-answer circuit may include: a first edge D flip-flop and a first NOR gate. The second rush-answer circuit may include: a second edge D flip-flop and a second NOR gate. To facilitate understanding of the working principles of the first rush-answer circuit and the second rush-answer circuit, the working principle of the edge D flip-flop will be introduced below.

[0071] See Figure 2 , Figure 2 which is a schematic diagram of an edge D flip-flop provided by an embodiment of the present application. As Figure 2 can be seen, the input terminals of the edge D flip-flop include: a clock terminal CLK, which is effective for rising-edge triggering; a clear terminal can also be represented by , which is effective for low-level; a preset terminal can also be represented by , which is effective for low-level. When the input signal of the clear terminal is at a low level, the clear terminal is in an effective state, and the output terminal Q outputs a low level; when the input signal of the preset terminal is at a low level, the preset terminal is in an effective state, and the output terminal Q outputs a high level. When both the clear terminal and the preset terminal are at a high level, when the clock terminal CLK changes from a low level to a high level, at the rising edge, the level signal of the output terminal Q is consistent with the level signal of the input terminal D at this time. As Figure 3 shows, it is a schematic diagram of the input terminal signal and the output terminal signal of the edge D flip-flop. As Figure 3 can be seen, there are a total of 5 rising edges at the clock terminal CLK. At the t0 moment, when the first rising edge arrives, at this time, both the clear terminal and the preset terminal are at a high level and in an ineffective state, so the output terminal Q is consistent with the input terminal D in level, that is, Q changes from a low level to a high level. At the t1 moment, the clear terminal becomes effective for low level, so the output terminal Q becomes a low level. At the t2 moment, the second rising edge arrives. At this time, the clear terminal is still effective for low level, so the output terminal Q remains at a low level. At the t3 moment, the third rising edge arrives. At this time, both the clear terminal and the preset terminal are at a high level and in an ineffective state, so the output terminal Q is consistent with the input terminal D. At the t3 moment, the input terminal D is at a low level, so the output terminal Q remains at a low level. At the t4 moment, the preset terminal becomes effective for low level, so the output terminal Q becomes a high level. At the t5 moment, the fourth rising edge arrives. At this time, the clear terminal and the preset terminal All are in the high-level invalid state, so the output terminal Q is consistent with the input terminal D. At t5, the input terminal D is low, so the output terminal Q changes from high level to low level. At t6, the fifth rising edge arrives, and the reset terminal and preset end Both are in the high-level invalid state, so the output terminal Q is consistent with the input terminal D. At t6, the input terminal D is at a high level, so the output terminal Q changes from a low level to a high level.

[0072] Based on this, the following will introduce the working principle of the CAN wake-up source identification system in combination with a specific application scenario. Figure 4 , Figure 4 A schematic diagram of another CAN wake-up source identification system provided in an embodiment of the present application.

[0073] In this application scenario, the first CAN chip and the second CAN chip can be exemplified by the TJA1145A chip, and the first edge-triggered D trigger and the second edge-triggered D trigger can be exemplified by the 7474 edge-triggered D trigger. CAN 1 represents the first CAN chip, CAN 2 represents the second CAN chip, Q1 represents the first voltage conversion circuit, Q2 represents the second voltage conversion circuit, the first answer circuit is composed of the first edge-triggered D trigger D1 and the first NOR gate F1, and the second answer circuit is composed of the second edge-triggered D trigger D2 and the second NOR gate F2. The connection relationship between CAN 1, CAN 2, SBC and MCU is not described in detail. Figure 4 It is directly drawn in that CAN1 and CAN2 have MCU voltage signal input terminals, indicating that CAN 1 and CAN 2 are both connected to the MCU, and SBC has an MCU voltage signal output terminal, indicating that SBC is connected to the MCU.

[0074] In this application scenario, when CAN 1 receives the wake-up instruction sent by the CAN bus, it can generate the first wake-up signal according to the wake-up instruction, that is, the INH pin outputs a 12v voltage signal, and sends the 12v voltage signal to the SBC and Q1. When Q1 receives the 12v voltage signal, the 12v voltage signal can be converted into a first trigger signal as the clock end CLK signal of D1. D1 outputs a 5v wake-up signal according to the 5v voltage signal at the input end, and sends the wake-up signal to the MCU. Among them, the 5v voltage signal at the input end of D1 can be provided by other chips in the circuit, such as a low-dropout linear regulator LDO chip. After the enable end of the SBC receives the 12v voltage signal, the wake-up function is realized. The 12v voltage signal is used as the power input end of the SBC, and then a 5v voltage signal is output to the MCU and other circuit parts, such as CAN 1 and CAN 2. At this time, the MCU is powered on after receiving the 5v voltage signal sent by the SBC and is in normal working state.

[0075] After CAN 2 receives a 5V voltage signal, it is also powered on, can output a 12V voltage signal, and D2 converts the 12V voltage signal into a second trigger signal, which is used as the CLK signal for the clock terminal of D2 to trigger D2 to work. From the fact that D1 outputs a 5V voltage signal, it can be known that the output terminal of D1 is connected to the input terminal of F1. Since F1 is a NOR gate, when there is any high-level signal at the input terminal, a low-level signal is output. From Figure 4 it can be known that the output terminal of F1 is connected to the clear terminal of D2 and the clear terminal is active low, so the output terminal of D2 remains low at this time, and thus D2 cannot output a wake-up signal to the MCU. The other input terminals of F1 and F2 are both connected to the CLEAR terminal of the MCU, which is default low level. So both input terminals of F2 are low level, and the output terminal is high level. The output terminal of F2 is connected to the clear terminal of D1 is in a high-level invalid state, so D1 can output a wake-up signal. Therefore, the MCU only receives the wake-up signal sent by D1 and can identify that the wake-up source is CAN 1.

[0076] Similarly, the working principle of the CAN 2 chip waking up after receiving the wake-up instruction is as described in the above embodiment and will not be elaborated here.

[0077] When the BMS system enters the sleep state, the MCU first sends a sleep instruction to the first CAN chip and the second CAN chip to control the first CAN chip and the second CAN chip to power off, and then sends a CLEAR signal to clear the wake-up signal in the wake-up circuit. For example, when the first CAN chip wakes up the system, it sends a CLERA signal to clear the wake-up signal in the first wake-up circuit. Refer to Figure 5a and Figure 5b , taking the first CAN chip receiving the wake-up instruction first as an example for illustration, so the first CAN chip outputs a voltage signal prior to the second CAN chip. Figure 5a represents the signal change in the circuit when the first CAN chip wakes up the system, Figure 5b represents the signal change in the circuit when the system is in the sleep state. Figure 5a and Figure 5b The change from low level to high level shown indicates the presence of an output signal. CAN 1_INH represents the INH pin of the first CAN chip, and CAN 1_WAKE represents the wake-up signal of the first CAN chip. From Figure 5a it can be known that when the first CAN chip outputs a wake-up signal, the second CAN chip does not output a wake-up signal, so the MCU can identify the wake-up source. In Figure 5bIn the embodiment, when the system enters sleep mode, the MCU first controls the first CAN chip and the second CAN chip to power off, and then sends a CLEAR signal to clear the wake-up signal, after which the MCU and the SBC are both powered off, and the system enters sleep mode. The principle of waking up the system by the first CAN chip and the second CAN chip is referred to in the above embodiment, and will not be repeated here.

[0078] The CAN wake-up source identification system provided in the embodiment of the present application can utilize the answering circuit in the system to send one wake-up signal to the MCU when multiple CAN chips send wake-up signals to the MCU, so that the MCU can identify the CAN chip that wakes up the system based on the received wake-up signal.

[0079] Based on the above system embodiment, the embodiment of the present application also provides a method for identifying a CAN wake-up source, which will be introduced below in conjunction with the accompanying drawings.

[0080] See also Figure 6 , Figure 6 A schematic diagram of a method for identifying a CAN wake-up source provided in an embodiment of the present application.

[0081] The method is applied to the CAN wake-up source identification system provided by the above system embodiment, the system includes: a first CAN chip, a second CAN chip, a first wake-up circuit, a second wake-up circuit, an SBC and an MCU, and the method mainly includes the following steps:

[0082] S601: The first CAN chip receives a wake-up instruction from the CAN bus and generates a first wake-up signal;

[0083] S602: The SBC implements a wake-up function according to the first wake-up signal, and outputs a voltage signal to the MCU, the first CAN chip, and the second CAN chip;

[0084] S603: The first wake-up circuit converts the first wake-up signal into a third wake-up signal, and sends the third wake-up signal to the MCU;

[0085] S604: The second CAN chip generates a second wake-up signal according to the voltage signal;

[0086] S605: The first wake-up circuit shields the function of the second wake-up circuit;

[0087] S606: The MCU receives a voltage signal to power on, and identifies a wake-up source based on the received third wake-up signal.

[0088] The method provided in this embodiment is described by taking the case where the first CAN chip first receives the wake-up instruction of the CAN bus as an example. Therefore, the first wake-up circuit can mask the second wake-up circuit, resulting in the second wake-up circuit being unable to generate a wake-up signal. As a result, the MCU can only receive the wake-up signal of the first CAN chip and identify that the first CAN chip wakes up the system. The working principle of the first CAN chip waking up the system can be referred to the above system embodiment and will not be elaborated here.

[0089] When the system enters the sleep state, the MCU can control the first CAN chip and the second CAN chip to enter the sleep state, that is, power down, and then send a CLEAR signal to clear the third wake-up signal in the first wake-up circuit.

[0090] Based on this, the embodiment of the present application also provides a method for identifying a CAN wake-up source. Refer to Figure 7 , Figure 7 which is the schematic diagram of another method for identifying a CAN wake-up source provided by the embodiment of the present application.

[0091] This method takes the case where the second CAN chip first receives the wake-up instruction of the CAN bus as an example. This method mainly includes the following steps:

[0092] S701: The second CAN chip receives the wake-up instruction of the CAN bus and generates a fifth wake-up signal;

[0093] S702: The SBC realizes the wake-up function according to the fifth wake-up signal and outputs a voltage signal to the MCU, the first CAN chip, and the second CAN chip;

[0094] S703: The second wake-up circuit converts the fifth wake-up signal into a sixth wake-up signal and sends the sixth wake-up signal to the MCU;

[0095] S704: The first CAN chip generates a seventh wake-up signal according to the voltage signal;

[0096] S705: The second wake-up circuit masks the function of the first wake-up circuit;

[0097] S706: The MCU receives the voltage signal to power on and identifies the wake-up source based on the received sixth wake-up signal.

[0098] When the second CAN chip first receives the wake-up instruction of the CAN bus, it can generate a wake-up signal and send it to the MCU. At this time, the second wake-up circuit can mask the first wake-up circuit, resulting in the first wake-up circuit being unable to generate a wake-up signal. Therefore, the MCU can only receive the wake-up signal of the second CAN chip and identify that the second CAN chip wakes up the system.

[0099] For the beneficial effects of the CAN wake-up source identification method provided by the embodiments of the present application, refer to the above system embodiments and will not be elaborated here.

[0100] Based on the above system embodiments and method embodiments, the present application further provides a CAN wake-up source identification device. Refer to Figure 8 , Figure 8 which is a schematic diagram of a CAN wake-up source identification device provided by the present application.

[0101] The device 800 includes: a memory 801 and a processor 802;

[0102] The memory 801 is used to store relevant program codes;

[0103] The processor 802 is used to call the program codes and execute the CAN wake-up source identification method described in the above method embodiments.

[0104] In addition, the embodiments of the present application further provide a computer-readable storage medium, which is used to store a computer program, and the computer program is used to execute the CAN wake-up source identification method described in the above method embodiments.

[0105] It should be noted that the various embodiments in this specification are described in a progressive manner. The key point of each embodiment is to illustrate the differences from other embodiments. The same or similar parts among the various embodiments can be referred to each other. In particular, for system or device embodiments, since they are basically similar to method embodiments, the description is relatively simple, and the relevant parts can refer to the partial description of the method embodiments. The device embodiments described above are only illustrative. The units or modules described as separate components may or may not be physically separated. The components shown as units or modules may or may not be physical modules, that is, they may be located in one place or distributed to multiple network units. Some or all of the units or modules can be selected according to actual needs to achieve the purpose of the solution of this embodiment. Those of ordinary skill in the art can understand and implement it without creative efforts.

[0106] It should be understood that in this application, "at least one (item)" means one or more, and "a plurality" means two or more. "And / or" is used to describe the association relationship of associated objects and indicates that there can be three relationships. For example, "A and / or B" can mean: only A exists, only B exists, and both A and B exist at the same time. Among them, A and B can be singular or plural. The character " / " generally represents an "or" relationship between the associated objects before and after. "At least one (one)" or its similar expression below refers to any combination of these items, including any combination of single item (one) or plural items (ones). For example, at least one (one) of a, b or c can mean: a, b, c, "a and b", "a and c", "b and c", or "a and b and c", where a, b, c can be single or multiple.

[0107] It should also be noted that in this article, relational terms such as first and second are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "include", "comprise" or any other variant thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements not only includes those elements, but also includes other elements not expressly listed, or also includes elements inherent to such process, method, article or device. Without further limitation, an element defined by the statement "including one..." does not exclude the existence of additional identical elements in the process, method, article or device including the said element.

[0108] The steps of the methods or algorithms described in connection with the embodiments disclosed herein can be implemented directly in hardware, software modules executed by a processor, or a combination of both. The software modules can be placed in a random access memory (RAM), internal memory, read-only memory (ROM), electrically programmable ROM, electrically erasable programmable ROM, registers, hard disk, removable disk, CD-ROM, or any other form of storage medium well-known in the technical field.

[0109] The above description of the disclosed embodiments enables those skilled in the art to implement or use this application. Various modifications to these embodiments will be apparent to those skilled in the art, and the general principles defined herein can be implemented in other embodiments without departing from the spirit or scope of this application. Therefore, this application will not be limited to the embodiments shown herein, but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A recognition system for CAN wake-up sources, characterized in that, the system includes: a first CAN chip, a second CAN chip, a first wake-up circuit, a second wake-up circuit, a system base chip SBC, and a micro-control unit MCU; the first CAN chip is used to receive a wake-up instruction or voltage signal of the CAN bus, generate a first wake-up signal, and send the first wake-up signal to the SBC; the second CAN chip is used to receive a wake-up instruction or voltage signal of the CAN bus, generate a second wake-up signal, and send the second wake-up signal to the SBC; the first wake-up circuit is used to process the first wake-up signal to obtain a third wake-up signal, and send the third wake-up signal to the MCU; the second wake-up circuit is used to process the second wake-up signal to obtain a fourth wake-up signal, and send the fourth wake-up signal to the MCU. The first wake-up circuit is connected to the second wake-up circuit, and both the first wake-up circuit and the second wake-up circuit have a rush-answer function; the SBC is used to implement a wake-up function according to the first wake-up signal or the second wake-up signal, and output the voltage signal to the MCU, the first CAN chip, and the second CAN chip; the MCU is used to receive the voltage signal to power on, and identify the wake-up source based on the received wake-up signal, and the wake-up signal is the third wake-up signal or the fourth wake-up signal; the first wake-up circuit includes: a first voltage conversion circuit and a first rush-answer circuit; the first voltage conversion circuit is used to convert the first wake-up signal into a first trigger signal, and send the first trigger signal to the first rush-answer circuit; the first rush-answer circuit is used to receive the first trigger signal, generate the third wake-up signal, and at the same time shield the function of the second wake-up circuit, and the second wake-up circuit cannot convert the second wake-up signal into a fourth wake-up signal and send it to the MCU; the second wake-up circuit includes: a second voltage conversion circuit and a second rush-answer circuit; the second voltage conversion circuit is used to convert the second wake-up signal into a second trigger signal, and send the second trigger signal to the second rush-answer circuit; the second rush-answer circuit is used to receive the second trigger signal, generate the fourth wake-up signal, and at the same time shield the function of the first wake-up circuit, and the first wake-up circuit cannot convert the first wake-up signal into a third wake-up signal and send it to the MCU.

2. The system according to claim 1, characterized in that, the first rush-answer circuit includes: a first edge D flip-flop and a first NOR gate; the second rush-answer circuit includes: a second edge D flip-flop and a second NOR gate.

3. The system according to claim 2, characterized in that, the output end of the first NOR gate is connected to the input end of the second edge D flip-flop.

4. A method for recognizing a CAN wake-up source, characterized in that, The method is applied to a CAN wake-up source identification system, which includes: a first CAN chip, a second CAN chip, a first wake-up circuit, a second wake-up circuit, an SBC, and an MCU. The method includes: The first CAN chip receives a wake-up instruction from the CAN bus and generates a first wake-up signal. The SBC implements a wake-up function according to the first wake-up signal and outputs a voltage signal to the MCU, the first CAN chip, and the second CAN chip. The first wake-up circuit converts the first wake-up signal into a third wake-up signal and sends the third wake-up signal to the MCU. The second CAN chip generates a second wake-up signal according to the voltage signal. The first wake-up circuit shields the function of the second wake-up circuit. The MCU receives the voltage signal to power on and identifies the wake-up source based on the received third wake-up signal.

5. According to the method described in claim 4, it is characterized in that the method further includes: The MCU controls the first CAN chip and the second CAN chip to enter the sleep state and sends a CLEAR signal to clear the third wake-up signal in the first wake-up circuit.

6. A method for identifying a CAN wake-up source, it is characterized in that the method is applied to a CAN wake-up source identification system, which includes: a first CAN chip, a second CAN chip, a first wake-up circuit, a second wake-up circuit, an SBC, and an MCU. The method includes: The second CAN chip receives a wake-up instruction from the CAN bus and generates a fifth wake-up signal. The SBC implements a wake-up function according to the fifth wake-up signal and outputs a voltage signal to the MCU, the first CAN chip, and the second CAN chip. The second wake-up circuit converts the fifth wake-up signal into a sixth wake-up signal and sends the sixth wake-up signal to the MCU. The first CAN chip generates a seventh wake-up signal according to the voltage signal. The second wake-up circuit shields the function of the first wake-up circuit. The MCU receives the voltage signal to power on and identifies the wake-up source based on the received sixth wake-up signal.

7. A device for identifying a CAN wake-up source, it is characterized in that the device includes: a memory and a processor; the memory is used to store relevant program codes; the processor is used to call the program codes and execute the method for identifying a CAN wake-up source according to any one of claims 4 to 6.

8. A computer-readable storage medium, it is characterized in that the computer-readable storage medium is used to store a computer program, and the computer program is used to execute the method for identifying a CAN wake-up source according to any one of claims 4 to 6.

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