USB mode switching circuit and method, in-vehicle infotainment system and vehicle

Abstract

The invention relates to the technical field of vehicle-mounted electronic systems, and discloses a USB mode switching circuit and method, a vehicle machine system and a vehicle. The USB mode switching circuit is provided with a first controlled switch and a second controlled switch to construct a two-stage control circuit which is directly controlled by a main processor and indirectly controlled by a coprocessor; the first controlled switch receives a high-level reference signal and a concentrator control function, and the second controlled switch realizes state intervention of the coprocessor on the first controlled switch. The structure does not need to depend on complex software link or screen operation, the concentrator mode switching is directly controlled through the level signal, the failure risk of a traditional single control path is avoided, it is ensured that the first working mode and the second working mode of the concentrator can be stably switched when the main processor or the coprocessor works normally, and the system reliability is improved. Reliability and response speed of vehicle-mounted machine USB mode switching are improved, and multi-scene working requirements of a vehicle-mounted machine system are met.

Description

Technical Field

[0001] This invention relates to the field of automotive electronic systems technology, specifically to USB mode switching circuits, methods, vehicle infotainment systems, and vehicles. Background Technology

[0002] For dual-system in-vehicle infotainment systems (i.e., systems containing both a main processor and a coordinator processor), debugging relies on a single USB mode. This requires clicking a switch button on the central control screen within the engineering mode APK (Android application package). The system middleware then sends data via the Serial Peripheral Interface (SPI) to the MCU to switch between USB and ADB (Android Debug Bridge) modes. This process is highly dependent on the operation of the central control screen, the functionality of the engineering mode APK, and the stability of the system middleware. In scenarios such as missing screens, touch malfunctions, or a black screen, switching to ADB mode becomes impossible, hindering development, debugging, and troubleshooting. Summary of the Invention

[0003] In view of this, the present invention provides a USB mode switching circuit, method, vehicle infotainment system and vehicle to solve the problem in the related art that USB mode switching cannot be performed when the vehicle infotainment system screen is abnormal in the case of dual system architecture.

[0004] In a first aspect, the present invention provides a USB mode switching circuit applied to an in-vehicle infotainment system, the in-vehicle infotainment system including a main processor and a coprocessor, the USB interface of the in-vehicle infotainment system being connected to an external hub, the USB mode switching circuit including a first controlled switch and a second controlled switch, wherein the control terminal of the first controlled switch is connected to the signal output terminal of the main processor and the first terminal of the second controlled switch respectively, the first terminal is connected to a high-level signal and the mode control terminal of the hub respectively, and the second terminal is grounded;

[0005] The control terminal of the second controlled switch is connected to the signal output terminal of the coprocessor, and the other terminal is grounded; The hub switches to a first operating mode when a high-level signal is received, and switches to a second operating mode when a low-level signal is received.

[0006] This invention constructs a two-level control circuit by setting a first controlled switch and a second controlled switch, where the main processor directly controls the circuit and the coprocessor indirectly controls it. The first controlled switch receives a high-level reference signal and performs hub control functions, while the second controlled switch enables the coprocessor to intervene in the state of the first controlled switch. This structure eliminates the need for complex software links or screen operations, directly controlling hub mode switching through level signals. This avoids the failure risk of traditional single control paths, ensuring stable switching between the first and second operating modes of the hub when either the main processor or the coprocessor is working normally. This improves the reliability and response speed of the vehicle's USB mode switching, adapting to the multi-scenario operating needs of the vehicle system.

[0007] In one alternative implementation, both the first controlled switch and the second controlled switch are transistors.

[0008] This invention employs transistors for both the first and second controlled switches. Leveraging the simple structure, low cost, and rapid switching response of transistors, the hardware complexity and manufacturing cost of the USB mode switching circuit are reduced. The on / off state of the transistors can be precisely controlled by level signals, ensuring stable transmission of control commands from the main processor and coprocessor. This guarantees accurate transmission of high / low level signals to the hub, avoiding signal distortion or delay during mode switching. Simultaneously, the transistors enhance the circuit's stability and durability, making it suitable for long-term operation scenarios in automotive infotainment systems.

[0009] In one optional implementation, the USB mode switching circuit further includes: An external control interface board is connected to the control terminal of the second controlled switch. In response to an operation command, the external control interface board outputs a first level signal to the control terminal of the second controlled switch so that both the second controlled switch and the first controlled switch are turned on. The hub is connected to a low level signal.

[0010] This invention adds an external control interface board connected to the control terminal of the second controlled switch, enabling it to respond to operation commands by outputting a first-level signal. This forces both the first and second controlled switches to conduct, allowing the hub to switch to a low-level signal mode. This provides an emergency control path independent of the main processor and coprocessor. In abnormal scenarios such as vehicle system crashes or main / coprocessor failures, USB mode switching can be achieved through external operation without relying on system software. This solves the pain point of traditional solutions being unable to debug in scenarios such as system crashes or abnormal startup in engineering mode, providing a reliable emergency debugging channel for vehicle system development and maintenance, and improving development efficiency.

[0011] In one optional implementation, the vehicle infotainment system is an Android system, and the vehicle infotainment system further includes: a vehicle infotainment screen; The vehicle screen responds to the user's working mode switching command by sending a working mode switching signal to the main processor; The main processor sends a mode switching protocol to the coprocessor based on the working mode switching signal; After receiving the mode switching protocol, the coprocessor outputs a high-level signal to the control terminal of the second controlled switch through its signal output terminal.

[0012] This invention, when the vehicle's infotainment screen responds to a user command, sends a switching signal to the main processor. The main processor then notifies the coprocessor to control the second controlled switch via a mode switching protocol. This retains the familiar USB mode switching method for screen operation, adapting to mode switching needs in common usage scenarios. Through the coordinated operation of the main processor and coprocessor, it ensures that screen operation commands are accurately converted into hardware level signals, achieving stable hub mode switching. This balances user convenience with reliable mode switching, conforming to the usage habits of Android vehicle infotainment systems.

[0013] In one alternative implementation, when the main processor fails to send a mode switching protocol to the coprocessor, or when the main processor's USB mode switching process is woken up, the main processor outputs a high-level signal to the control terminal of the second controlled switch through the main processor's signal output terminal.

[0014] When the main processor fails to send the mode switching protocol to the coprocessor, or when the USB mode switching process is woken up, this invention directly outputs a high-level signal to the second controlled switch. This avoids mode switching failures caused by communication link failures between the main processor and the coprocessor. It also supports actively triggering mode switching by waking up the switching process, eliminating the need for a screen or coprocessor as an intermediary. This reduces intermediate steps and dependencies in mode switching, improving the success rate and response speed of USB mode switching. It is particularly suitable for scenarios requiring rapid mode switching during development and debugging, ensuring development efficiency.

[0015] In one optional implementation, the first terminal of the first controlled switch is also connected to the interrupt detection interface of the main processor. The interrupt triggering method of the main processor is edge triggering. Based on the interrupt signal fed back by the interrupt detection interface, the main processor feeds back the working mode switching result to the USB mode switching process.

[0016] This invention connects the first terminal of the first controlled switch to the interrupt detection interface of the main processor and employs an edge-triggered method, enabling the main processor to provide feedback on the mode switching result to the USB mode switching process via an interrupt signal. Because the edge-triggered method can quickly capture level changes, it ensures that the main processor promptly obtains the hub mode switching status. The feedback result allows the switching process to accurately determine whether the switching was successful, facilitating timely handling of abnormal situations such as switching failures, avoiding invalid operations or mode confusion, improving the closed-loop control capability of USB mode switching, and ensuring the stable operation of the vehicle's USB function.

[0017] In one alternative implementation, the main processor is a SOC chip and the coprocessor is an MCU chip.

[0018] This invention utilizes a dual-chip architecture of SOC chip and MCU chip in the vehicle infotainment system. The SOC chip ensures flexible control at the software level, while the MCU chip ensures real-time response at the hardware level. This allows USB mode switching to have both the convenience of software control and the stability of hardware control, thus adapting to the complex working scenarios of the vehicle infotainment system.

[0019] In a second aspect, the present invention provides a USB mode switching method, applied to a USB mode switching circuit as provided in the first aspect and any of its optional embodiments, the method comprising: When the main processor outputs a first-level signal to the control terminal of the first controlled switch, the first controlled switch is turned on, the hub receives a low-level signal, and switches from the first working mode to the second working mode. When the signal output terminal of the coprocessor outputs a first-level signal to the control terminal of the first controlled switch, both the second controlled switch and the first controlled switch are turned on, the hub receives a low-level signal, and switches from the first working mode to the second working mode. When the main processor outputs a second-level signal to the control terminal of the first controlled switch and the coprocessor outputs a second-level signal to the control terminal of the first controlled switch, the first controlled switch is turned off, the hub receives a high-level signal, and switches from the second working mode to the first working mode.

[0020] This invention achieves hub mode switching by controlling the on / off logic of the first and second controlled switches when the main processor and coprocessor output different level signals. This ensures accurate mode switching through both direct control by the main processor and indirect control by the coprocessor, avoiding switching failures caused by chaotic control logic. Furthermore, by establishing a correspondence between different level signals and mode switching, the switching process becomes predictable and reproducible, improving the consistency and reliability of USB mode switching and adapting to the diverse control needs of in-vehicle infotainment systems under normal operating conditions.

[0021] In an optional implementation, the method further includes: When the external control interface board responds to the operation command and outputs a first-level signal to the control terminal of the second controlled switch, both the second controlled switch and the first controlled switch are turned on, the hub receives a low-level signal, and switches from the first working mode to the second working mode.

[0022] This invention, through the addition of an external control interface board, can forcibly activate the second and first controlled switches when it outputs a first-level signal in response to an operation command, thereby achieving hub mode switching. It provides a dedicated switching path for abnormal scenarios, without relying on the main processor, coprocessor, or system software. Even if the vehicle system crashes or experiences hardware failure, mode switching can still be completed through external operation. This solves the pain point of traditional solutions being unable to debug in special abnormal scenarios, providing a flexible and efficient emergency means for vehicle system development and maintenance, and ensuring the smooth progress of vehicle system debugging.

[0023] Thirdly, the present invention provides a vehicle infotainment system, the vehicle infotainment system comprising: a main processor and a coprocessor, a USB interface external hub of the vehicle infotainment system, and the vehicle infotainment system further comprising: a USB mode switching circuit as provided in the first aspect and any of its optional embodiments.

[0024] The in-vehicle infotainment system provided by this invention integrates a USB mode switching circuit, freeing the system from dependence on a single control path. It enables USB mode switching through conventional operations while also handling special scenarios such as system anomalies and communication failures, thus improving the stability and adaptability of the in-vehicle infotainment system's USB function. Simultaneously, it simplifies the hardware architecture of the in-vehicle infotainment system's USB mode switching, reducing the system's reliance on complex software links and expensive peripherals, thus balancing user experience with development and maintenance efficiency.

[0025] Fourthly, the present invention provides a vehicle including the vehicle infotainment system as provided in the third aspect.

[0026] The vehicle provided by this invention, equipped with the in-vehicle infotainment system provided in this embodiment, enables the vehicle's USB function to have reliable mode switching capabilities. Through the multi-level control links and emergency switching channels of the in-vehicle infotainment system, it ensures stable USB mode switching in various scenarios such as driving and parking for debugging, adapting to diverse needs such as charging, data transmission, and debugging. Simultaneously, the high reliability of the in-vehicle infotainment system's mode switching reduces the risk of USB function failure, improves the stability of the vehicle's electronic system, provides convenience for users and after-sales maintenance, and enhances the vehicle's product competitiveness. Attached Figure Description

[0027] To more clearly illustrate the specific embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the specific embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0028] Figure 1 This is a schematic diagram of the USB mode switching circuit according to an embodiment of the present invention; Figure 2 This is a flowchart of a USB mode switching method according to an embodiment of the present invention; Figure 3 This is a schematic diagram of the system architecture for implementing USB mode switching in in-vehicle infotainment systems in related technologies; Figure 4 This is a schematic diagram of the system architecture for implementing USB mode switching in a vehicle infotainment system according to an embodiment of the present invention; Figure 5 This is a schematic diagram of the USB mode switching module in the main processor according to an embodiment of the present invention; Figure 6 This is a schematic diagram of the structure of a vehicle infotainment system according to an embodiment of the present invention; Figure 7 This is a structural schematic diagram of a vehicle according to an embodiment of the present invention. Detailed Implementation

[0029] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0030] It is understood that before using the technical solutions disclosed in the various embodiments of the present invention, users should be informed of the types, scope of use, and usage scenarios of the personal information involved in the present invention and their authorization should be obtained in accordance with relevant laws and regulations through appropriate means.

[0031] The terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of this invention, "a plurality of" means two or more, unless otherwise explicitly specified.

[0032] In related technologies, vehicle infotainment system debugging relies on a single USB mode, requiring switching to ADB mode via the central control screen. However, switching to ADB mode fails in scenarios where a screen is unavailable, touchscreen malfunctions, or the screen is black, impacting development, debugging, and troubleshooting. Furthermore, switching to ADB mode also fails in other abnormal scenarios such as repeated system middleware crashes or abnormal startup in engineering mode. In addition, in the early stages of vehicle infotainment system project development, the entire notification chain for SPI-based mode switching to the MCU is not yet established; the inability to switch to ADB mode severely hinders the work of parallel developers. In actual development, the high cost of central control screens limits the availability of one for each employee, further restricting the development and debugging efficiency of vehicle infotainment systems.

[0033] To address the aforementioned issues, this invention provides a USB mode switching solution applicable to dual-system vehicle infotainment architectures. This solution is achieved through hardware and software co-design: it eliminates the need to switch between USB host mode and device mode via the screen; it reduces development reliance on the central control screen; it provides an emergency debugging channel for abnormal scenarios, improving development and vehicle debugging efficiency; and it eliminates the need for a separate default device version release for the MCU during the supplier's core board production and testing process.

[0034] This invention provides a USB mode switching circuit for use in an in-vehicle infotainment system. The system includes a main processor and a coprocessor, with a USB interface connected to an external hub. It should be noted that this embodiment uses a System-on-a-Chip (SoC) chip as the main processor and an MCU chip as the coprocessor. This embodiment utilizes a dual-chip architecture (SoC and MCU) for the in-vehicle infotainment system. The SoC chip ensures flexible software-level control, while the MCU chip ensures real-time hardware-level response. This allows USB mode switching to combine the convenience of software control with the stability of hardware control, adapting to the complex operating requirements of in-vehicle infotainment systems. Figure 1 This is a schematic diagram of the USB mode switching circuit according to an embodiment of the present invention, as shown below. Figure 1 As shown, the USB mode switching circuit includes: A first controlled switch A and a second controlled switch B are configured such that the control terminal of the first controlled switch A is connected to the signal output terminal of the main processor SOC and the first terminal of the second controlled switch B, the first terminal of which is connected to a high-level signal and the mode control terminal of the hub, and the second terminal is grounded; the control terminal of the second controlled switch B is connected to the signal output terminal of the coprocessor MCU, and the other terminal is grounded; the hub switches to the first operating mode when a high-level signal is received and switches to the second operating mode when a low-level signal is received.

[0035] For example, in Figure 1 In this circuit, the high-level signal is provided by the power supply VCC. For example, the power supply voltage of VCC is 1.8V, and this 1.8V power supply VCC provides the reference level for mode switching of the hub. When the hub receives a 1.8V high-level signal, it switches to the first operating mode, and when it receives a low-level signal at ground potential, it switches to the second operating mode. For example, the first operating mode is host mode, and the second operating mode is device mode. Alternatively, the first operating mode can be set to device mode and the second operating mode to host mode as needed; this invention is not limited thereto.

[0036] This embodiment constructs a two-level control circuit by setting a first controlled switch and a second controlled switch, where the main processor directly controls the circuit and the coprocessor indirectly controls it. The first controlled switch receives a high-level reference signal and performs hub control functions, while the second controlled switch enables the coprocessor to intervene in the state of the first controlled switch. This structure does not rely on complex software links or screen operations, and directly controls the hub mode switching through level signals, avoiding the failure risk of traditional single control paths. It ensures that the first and second working modes of the hub can be stably switched when the main processor or the coprocessor is working normally, improving the reliability and response speed of the vehicle's USB mode switching and adapting to the multi-scenario working needs of the vehicle system.

[0037] Specifically, such as Figure 1 As shown, both the first controlled switch A and the second controlled switch B are transistors. It should be noted that in practical applications, the first controlled switch A and the second controlled switch B can also be MOSFETs, IGBTs, or other switching devices, as long as they can achieve the reference level switching function; this invention is not limited to these.

[0038] In this embodiment, both the first and second controlled switches utilize transistors. Leveraging the simple structure, low cost, and rapid switching response of transistors, the hardware complexity and manufacturing cost of the USB mode switching circuit are reduced. The on / off state of the transistors can be precisely controlled by level signals, stably transmitting control commands from the main processor and coprocessor. This ensures accurate transmission of high / low level signals to the hub, avoiding signal distortion or delay during mode switching. Simultaneously, the transistors enhance the circuit's stability and durability, making it suitable for long-term operation scenarios in vehicle infotainment systems.

[0039] In some optional implementations, the USB mode switching circuit described above further includes: An external control interface board is connected to the control terminal of the second controlled switch B. In response to an operation command, the external control interface board outputs a first-level signal to the control terminal of the second controlled switch B, so that both the second controlled switch B and the first controlled switch A are turned on, and the hub receives a low-level signal.

[0040] For example, such as Figure 1 The external control interface board shown is a small hardware board 101, which can be implemented using a small PCB board. It integrates a mode switching DIP switch / button. By operating the DIP switch / button, different level signals are provided to the second controlled switch B to control the second controlled switch B to be turned on or off. Alternatively, other separate detachable components capable of providing different level signals can also be used; this invention is not limited to these.

[0041] This embodiment adds an external control interface board connected to the control terminal of the second controlled switch, enabling it to respond to operation commands by outputting a first-level signal, forcing the second and first controlled switches to conduct, and allowing the hub to switch to a low-level signal mode. This provides an emergency control path independent of the main processor and coprocessor. In abnormal scenarios such as vehicle system crashes or main / coprocessor failures, USB mode switching can be achieved through external operation without relying on system software. This solves the pain point of traditional solutions being unable to debug in scenarios such as system crashes or abnormal startup in engineering mode, providing a reliable emergency debugging channel for vehicle system development and maintenance, and improving development efficiency.

[0042] In some optional implementations, the above-mentioned vehicle system is an Android system, and the vehicle system further includes: a vehicle screen; the vehicle screen responds to the user's working mode switching command and sends a working mode switching signal to the main processor SOC; the main processor SOC sends a mode switching protocol to the coprocessor MCU based on the working mode switching signal; after receiving the mode switching protocol, the coprocessor MCU outputs a high-level signal to the control terminal of the second controlled switch B through the signal output terminal of the coprocessor MCU.

[0043] Specifically, taking the main processor SOC as the SOC chip and the coprocessor MCU as the MCU chip as the MCU chip, the user triggers a touch event to switch the USB working mode by operating the vehicle screen. The vehicle screen distributes this touch event, i.e. the aforementioned working mode switching signal, to the engineering mode APP of the SOC chip. After receiving the touch event, the engineering mode APP recognizes the mode switch and then notifies the Android middleware in the SOC chip to send the mode switching protocol to the MCU chip. After receiving the corresponding notification, the Android middleware sends data via SPI to notify the MCU chip to switch the hub mode. The MCU chip notifies the hub to perform a mode switch by pulling the level signal of the GPIO pin high. After receiving the pulled level signal, the hub performs a mode switch.

[0044] In this embodiment, when the vehicle's infotainment screen responds to a user command, it sends a switching signal to the main processor. The main processor then notifies the coprocessor to control the second controlled switch via a mode switching protocol. This retains the familiar USB mode switching method for screen operation, adapting to mode switching needs in common usage scenarios. Through the coordinated efforts of the main processor and the coprocessor, screen operation commands are accurately converted into hardware level signals, achieving stable hub mode switching. This balances user convenience with reliable mode switching, conforming to the usage habits of the Android vehicle infotainment system.

[0045] Furthermore, when the main processor SOC fails to send the mode switching protocol to the coprocessor MCU, or when the USB mode switching process of the main processor SOC is woken up, it outputs a high-level signal to the control terminal of the second controlled switch B through the signal output terminal of the main processor SOC.

[0046] For example, if an Android middleware malfunction causes the SOC chip to fail to send the mode switching protocol to the MCU chip, or if the SOC chip's serial port receives communication data indicating mode switching, it can wake up the USB mode switching process inside the SOC chip. In this way, the SOC chip can directly notify the HUB to perform mode switching by pulling up the level signal of the GPIO pin. After receiving the pulled-up level signal, the HUB will perform mode switching.

[0047] In this embodiment, when the main processor fails to send the mode switching protocol to the coprocessor, or when the USB mode switching process is woken up, the main processor directly outputs a high-level signal to the second controlled switch. This avoids mode switching failures caused by communication link failures between the main processor and the coprocessor. It also supports actively triggering mode switching by waking up the switching process, eliminating the need for a screen or coprocessor as an intermediary. This reduces intermediate steps and dependencies in mode switching, improving the success rate and response speed of USB mode switching. It is particularly suitable for scenarios requiring rapid mode switching during development and debugging, ensuring development efficiency.

[0048] In some alternative implementations, such as Figure 1 As shown, the first terminal of the first controlled switch A is also connected to the interrupt detection interface of the main processor SOC. The interrupt triggering mode of the main processor SOC is edge-triggered. Based on the interrupt signal fed back by the interrupt detection interface, the main processor SOC feeds back the working mode switching result to the USB mode switching process.

[0049] For example, the interrupt detection interface of the SOC chip is directly connected to the first terminal of the first controlled switch A. The interrupt triggering mode of the SOC chip is set to edge triggering. That is, when a change in the level signal (from high level to low level or from low level to high level) is detected at the first terminal of the first controlled switch A, an interrupt signal is triggered. When the SOC chip receives the interrupt signal, it feeds it back to the USB mode switching process. The USB mode switching process determines whether the switching is successful based on the interrupt signal. For example, after the USB mode switching process is woken up, if the interrupt signal is received within a set time, the mode switching is determined to be successful. Otherwise, the mode switching is determined to be unsuccessful, and the SOC chip performs abnormal switching reminders and other processing.

[0050] This embodiment connects the first terminal of the first controlled switch to the interrupt detection interface of the main processor and adopts an edge-triggered method, enabling the main processor to feed back the mode switching result to the USB mode switching process via an interrupt signal. Since the edge-triggered method can quickly capture level changes, it ensures that the main processor promptly obtains the hub mode switching status. The feedback result allows the switching process to accurately determine whether the switching was successful, facilitating timely handling of abnormal situations such as switching failures, avoiding invalid operations or mode confusion, improving the closed-loop control capability of USB mode switching, and ensuring the stable operation of the vehicle's USB function.

[0051] This invention also provides a USB mode switching method, applicable to, for example... Figure 1 The USB mode switching circuit shown is... Figure 2 This is a flowchart of a USB mode switching method according to an embodiment of the present invention, such as... Figure 2 As shown, the process includes the following steps: In step S201, when the main processor outputs a first-level signal to the control terminal of the first controlled switch, the first controlled switch is turned on, the hub receives a low-level signal, and the operating mode is switched from the first operating mode to the second operating mode.

[0052] For example, the first level signal is a high level signal, which controls the first controlled switch to turn on, and the hub receives a low level signal, so that the hub switches from host mode to device mode.

[0053] In step S202, when the signal output terminal of the coprocessor outputs a first-level signal to the control terminal of the first controlled switch, both the second controlled switch and the first controlled switch are turned on, the hub receives a low-level signal, and switches from the first working mode to the second working mode.

[0054] For example, the first level signal is a high level signal, the second controlled switch is turned on, which in turn controls the first controlled switch to turn on, the hub receives a low level signal, and the hub switches from host mode to device mode.

[0055] In step S203, when the main processor outputs a second-level signal to the control terminal of the first controlled switch and the coprocessor outputs a second-level signal to the control terminal of the first controlled switch, the first controlled switch is turned off, the hub receives a high-level signal, and the second working mode is switched to the first working mode.

[0056] For example, the second level signal is a low level signal, which controls both the second controlled switch and the first controlled switch to turn off, and the hub receives a high level signal, switching the hub from device mode back to host mode.

[0057] This embodiment achieves hub mode switching by controlling the on / off logic of the first and second controlled switches when the main processor and coprocessor output different level signals. This ensures accurate mode switching through both direct control by the main processor and indirect control by the coprocessor, avoiding switching failures caused by chaotic control logic. Furthermore, by establishing a correspondence between different level signals and mode switching, the switching process becomes predictable and reproducible, improving the consistency and reliability of USB mode switching and adapting to the diverse control needs of the vehicle's infotainment system under normal operating conditions.

[0058] In some optional implementations, the above USB mode switching method further includes the following steps: Step a1: When the external control interface board responds to the operation command and outputs a first level signal to the control terminal of the second controlled switch, both the second and first controlled switches are turned on, the hub receives a low level signal, and switches from the first working mode to the second working mode.

[0059] For example, by operating the buttons or switches on the external control interface board, the user can trigger the external control interface board to output a high-level signal to the control terminal of the second controlled switch, thereby controlling the second controlled switch to turn on, and then controlling the first controlled switch to turn on. The hub receives a low-level signal, and the hub switches from host mode to device mode.

[0060] This embodiment utilizes an additional external control interface board. When the board outputs a first-level signal in response to an operation command, it can forcibly activate the second and first controlled switches, thereby achieving hub mode switching. This provides a dedicated switching path for abnormal scenarios, eliminating reliance on the main processor, coprocessor, or system software. Even if the vehicle system crashes or experiences hardware failure, mode switching can still be completed through external operation. This solves the pain point of traditional solutions being unable to debug in special abnormal scenarios, providing a flexible and efficient emergency measure for vehicle system development and maintenance, and ensuring the smooth progress of vehicle system debugging.

[0061] The working principle and process of the USB mode switching circuit provided in this embodiment of the invention will be described in detail below with reference to specific application examples.

[0062] By integrating the USB mode switching circuit into a multi-level HUB status control module, such as... Figure 1 As shown, the main components required to achieve USB mode switching are: SOC, MCU, HUB, external control interface board (also known as hardware board), and two NPN transistors (A and B). Among them, SOC has data processing and interface control capabilities, MCU is responsible for real-time control and signal interaction, HUB is an external expansion module that supports mode switching, hardware board is an external operation module for emergency control, and two NPN transistors are used as switching elements to achieve level control.

[0063] For example, the connection relationships of the various parts are as follows: The collector of A is connected to the mode control terminal and the 1.8V power output terminal of the HUB. The 1.8V power supply provides the reference level for mode switching of the HUB. The base of A forms a bidirectional connection, one end of which is connected to the GPIO control pin of the SOC and the other end is connected to the collector of B. The emitter of A is directly grounded, forming the reference point for the conduction loop of A.

[0064] The base of B forms a bidirectional connection, with one end connected to the control pin of the MCU and the other end connected to the output pin of the hardware board. The emitter of B is directly grounded, forming the reference point for the conduction loop of B. The collector of B is only connected to the base of A, and the conduction state of A is controlled by the level change.

[0065] The core control link of the aforementioned HUB state multi-level control module is as follows: the SOC outputs a level signal to the base of A through its GPIO pin, the MCU outputs a level signal to the base of B through its control pin, and the output signal of the hardware board is directly connected to the base of B, forming a parallel input with the MCU's control signal. The HUB's mode control state is determined by the collector level of A, indirectly controlled by the conduction states of A and B. Specifically, when the base of A is high, A is turned on, and its collector level is pulled low (close to ground potential); when the base of A is low, A is turned off, and its collector maintains a high level of 1.8V; when the base of B is high, B is turned on, and its collector level is pulled low (close to ground potential), thereby pulling the base level of A low; when the base of B is low, B is turned off, and its collector level is determined by the base input signal of A.

[0066] The HUB mode control signal transmission path includes: SOC direct control path: When the SOC outputs a high level, A is turned on → HUB receives a low level signal; when the SOC outputs a low level, A is turned off → HUB receives a 1.8V high level signal. MCU indirect control path: MCU outputs high level → B turns on → A base is pulled low → A turns off → HUB receives 1.8V high level signal; MCU outputs low level → B turns off → A state is controlled by SOC; Emergency control path for the small hardware board: When the small hardware board outputs a high level, B is turned on (same as the MCU high-level logic) → HUB receives a 1.8V high-level signal; when the small hardware board outputs a low level, B is turned off → state A is controlled by the SOC or MCU.

[0067] For example, the system architecture for implementing USB mode switching in the vehicle infotainment system in the related technology is as follows: Figure 3 As shown, the system architecture for implementing USB mode switching in the vehicle infotainment system of this embodiment is as follows: Figure 4 As shown, comparison Figure 3 and Figure 4 As can be seen, this embodiment mainly adds the following two data links: C-link: C1 notifies the USB mode switching module via serial port, and C2, the USB mode switching module, switches the HUB conversion mode by pulling the GPIO high and low.

[0068] D-link: D1 switches the HUB conversion mode by pulling the switch high or low through an external hardware board.

[0069] For example, the structure of the USB mode switching module in the main processor is as follows: Figure 5 As shown, the entire control flow of the main processor includes: A1: Initiates the USB mode switching process; A2: Notify the GPIO controller to pull the HUB status high or low on the corresponding GPIO pin of the multi-level control module; A3: Hardware signal, GPIO signal notifies the HUB status multi-level control module; A4: Hardware signal, the HUB status multi-level control module signal is fed back to the USB controller module; A5: Software signal, which returns the current HUB status of the SOC to the USB mode switching process, and the process determines whether the HUB mode switch was successful.

[0070] This embodiment employs a two-stage transistor switching structure to achieve multi-level control of the HUB by the SOC, MCU, and hardware board. The hardware board and MCU control the transistors in parallel to ensure control priority in emergency scenarios. The combination of a 1.8V power supply and transistors provides a stable mode switching signal for the HUB, avoiding the impact of voltage fluctuations. This embodiment creates a hardware-software collaborative dual-mode switching mechanism, achieving reliable mode switching through a combination of GPIO hardware control and software protocols. An emergency channel for abnormal scenarios is also established, allowing entry into debug mode via physical buttons or serial port even when the vehicle system crashes. This reduces reliance on the hardware screen, requiring only the hardware board, improving the development efficiency of the vehicle system and increasing system debugging methods in abnormal scenarios.

[0071] This invention also provides a vehicle infotainment system, such as... Figure 6 As shown, the vehicle infotainment system includes a main processor 601 and a coprocessor 602. The vehicle infotainment system's USB interface is connected to an external hub. The vehicle infotainment system also includes a USB mode switching circuit 603 provided in another embodiment of the present invention.

[0072] The vehicle infotainment system provided in this embodiment integrates a USB mode switching circuit, freeing it from dependence on a single control path. It can switch USB modes through conventional operations while also handling special scenarios such as system anomalies and communication failures, thus improving the stability and adaptability of the vehicle's USB functionality. Simultaneously, it simplifies the hardware architecture of the vehicle's USB mode switching, reduces the system's reliance on complex software links and expensive peripherals, and balances user experience with development and maintenance efficiency.

[0073] This invention also provides a vehicle, such as... Figure 7 As shown, the vehicle includes a vehicle infotainment system 701 provided in another embodiment of the present invention.

[0074] The vehicle provided in this embodiment, equipped with the in-vehicle infotainment system provided in this embodiment, enables the vehicle's USB function to have reliable mode switching capabilities. Through the multi-level control links and emergency switching channels of the in-vehicle infotainment system, it ensures stable USB mode switching in different scenarios such as driving and parking for debugging, adapting to diverse needs such as charging, data transmission, and debugging. Simultaneously, the high reliability of the in-vehicle infotainment system's mode switching reduces the risk of USB function failure, improves the stability of the vehicle's electronic system, provides convenience for users and after-sales maintenance, and enhances the vehicle's product competitiveness.

[0075] Although embodiments of the invention have been described in conjunction with the accompanying drawings, those skilled in the art can make various modifications and variations without departing from the spirit and scope of the invention, and such modifications and variations all fall within the scope defined in this application.

Claims

1. A USB mode switching circuit, applied to an in-vehicle infotainment system, the in-vehicle infotainment system comprising: The main processor and coprocessor, and the USB interface external hub of the vehicle system, are characterized in that the USB mode switching circuit includes: a first controlled switch and a second controlled switch, wherein, The control terminal of the first controlled switch is connected to the signal output terminal of the main processor and the first terminal of the second controlled switch, respectively. The first terminal is connected to the high-level signal and the mode control terminal of the hub, respectively, and the second terminal is grounded. The control terminal of the second controlled switch is connected to the signal output terminal of the coprocessor, and the other terminal is grounded; The hub switches to a first operating mode when a high-level signal is received, and switches to a second operating mode when a low-level signal is received.

2. The USB mode switching circuit according to claim 1, characterized in that, Both the first controlled switch and the second controlled switch are transistors.

3. The USB mode switching circuit according to claim 1, characterized in that, Also includes: An external control interface board is connected to the control terminal of the second controlled switch. In response to an operation command, the external control interface board outputs a first level signal to the control terminal of the second controlled switch so that both the second controlled switch and the first controlled switch are turned on. The hub is connected to a low level signal.

4. The USB mode switching circuit according to claim 1, characterized in that, The vehicle infotainment system is an Android system, and the vehicle infotainment system also includes: a vehicle screen; The vehicle screen responds to the user's working mode switching command by sending a working mode switching signal to the main processor; The main processor sends a mode switching protocol to the coprocessor based on the working mode switching signal; After receiving the mode switching protocol, the coprocessor outputs a high-level signal to the control terminal of the second controlled switch through its signal output terminal.

5. The USB mode switching circuit according to claim 4, characterized in that, When the main processor fails to send the mode switching protocol to the coprocessor, or when the main processor's USB mode switching process is woken up, the main processor outputs a high-level signal to the control terminal of the second controlled switch through the main processor's signal output terminal.

6. The USB mode switching circuit according to claim 5, characterized in that, The first terminal of the first controlled switch is also connected to the interrupt detection interface of the main processor. The interrupt triggering method of the main processor is edge triggering. Based on the interrupt signal fed back by the interrupt detection interface, the main processor feeds back the working mode switching result to the USB mode switching process.

7. The USB mode switching circuit according to any one of claims 1-6, characterized in that, The main processor is a SOC chip, and the coprocessor is an MCU chip.

8. A USB mode switching method, characterized in that, The method, applied to the USB mode switching circuit as described in any one of claims 1-7, comprises: When the main processor outputs a first-level signal to the control terminal of the first controlled switch, the first controlled switch is turned on, the hub receives a low-level signal, and switches from the first working mode to the second working mode. When the signal output terminal of the coprocessor outputs a first-level signal to the control terminal of the first controlled switch, both the second controlled switch and the first controlled switch are turned on, the hub receives a low-level signal, and switches from the first working mode to the second working mode. When the main processor outputs a second-level signal to the control terminal of the first controlled switch and the coprocessor outputs a second-level signal to the control terminal of the first controlled switch, the first controlled switch is turned off, the hub receives a high-level signal, and switches from the second working mode to the first working mode.

9. The USB mode switching method according to claim 8, characterized in that, The method further includes: When the external control interface board responds to the operation command and outputs a first-level signal to the control terminal of the second controlled switch, both the second controlled switch and the first controlled switch are turned on, the hub receives a low-level signal, and switches from the first working mode to the second working mode.

10. A vehicle infotainment system, characterized in that, The vehicle infotainment system includes a main processor and a coprocessor, a USB interface for connecting to an external hub, and further includes a USB mode switching circuit as described in any one of claims 1-7.

11. A vehicle, characterized in that, The vehicle includes the vehicle infotainment system as described in claim 10.

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