A Bluetooth master-slave dual-mode switching-based audio private transmission control method and a Bluetooth sound box system

Abstract

The application discloses a kind of audio private transmission control method and bluetooth speaker system based on bluetooth master-slave dual-mode switching, keep standard connection with host in slave mode through double virtual channel, simultaneously with historical pairing headset establishes pre-alive link;Based on multi-level priority arbitration mechanism, intercept and issue instruction, only response switch when idle;After response start instruction, private transmission is strongly bound with host mode, executes audio buffer locking, power amplifier mute, route switching and flow recovery in turn according to irreversible time sequence;And using the double partition of physical isolation, the pairing information of host and headset is solidified respectively.The method controls the time consumption of switching within 300ms, audio pause is not more than 100ms, realizes no perception experience;Completely solve multi-source instruction conflict, exempt from repeated pairing;Power amplifier mute and route switching are accurately synchronized, and privacy leakage is eliminated.In addition, through full-scene abnormality automatic fallback and highest priority hardware reset function, avoid dead end.

Description

Technical Field

[0001] This invention belongs to the field of wireless communication control technology, specifically an audio privacy transmission control method and Bluetooth speaker system based on Bluetooth master-slave dual-mode switching. Background Technology

[0002] With the widespread adoption of smart audio devices, smart Bluetooth speakers running Android have become the mainstream audio playback devices in homes and offices. Currently, the core protocol for Bluetooth audio transmission is the Advanced Audio Distribution Profile (A2DP), which primarily defines the slave role (A2DPSink) responsible for receiving audio and the master role (A2DPSource) responsible for sending audio. To meet users' needs for private listening in special scenarios such as at night or in public places, private audio transmission functions have emerged in the market. The core logic of this function is to switch the master / slave role of the device's Bluetooth, redirecting the audio stream played by the speaker to Bluetooth headphones, thereby achieving the effect of the speaker being muted while the headphones output sound alone.

[0003] However, existing audio privacy transmission technologies have several significant drawbacks in practical applications. First, existing master-slave switching schemes require disconnecting all Bluetooth connections and restarting the module, resulting in noticeable audio stream interruptions and delays, and often necessitating repeated phone pairing by the user. Second, existing multi-source controls (such as app commands, physical buttons, system restarts, etc.) lack priority arbitration mechanisms, easily leading to command conflicts and functional status errors. Furthermore, since master-slave modes share a single pairing storage area, pairing information between the phone and headphones is overwritten during mode switching, further increasing the user's operational burden. In addition, existing solutions lack fallback mechanisms for situations such as headphones not connecting or abnormal disconnections, and also lack precise timing control for amplifier switching and audio routing, easily leading to privacy leaks due to simultaneous sound from both ends or causing the device to become silent and unresponsive. Moreover, in the event of system software lag, users cannot perform the highest-priority hardware-level reset and repair via physical buttons.

[0004] In summary, existing Bluetooth speakers generally face serious technical bottlenecks when implementing private audio transmission, including poor audio continuity, susceptibility to system instability, cumbersome pairing management, and a lack of full-scenario fault tolerance and emergency recovery mechanisms. Therefore, to address these shortcomings, the industry urgently needs to develop a highly stable, user-friendly audio private transmission control method and system with comprehensive timing control and anomaly closed-loop mechanisms to completely resolve users' core pain points when switching between private listening modes. Summary of the Invention

[0005] The purpose of this invention is to provide an audio privacy transmission control method and a Bluetooth speaker system based on Bluetooth master-slave dual-mode switching, so as to solve the problem mentioned in the background art.

[0006] To solve the above-mentioned technical problems, the technical solution adopted by the present invention is as follows: A method for controlling private audio transmission based on Bluetooth master-slave dual-mode switching, applied to a Bluetooth speaker, includes the following control methods: Dual virtual channel establishment steps: In the default Bluetooth slave mode, maintain a standard audio connection with the first host device, and at the same time start low power Bluetooth scanning and establish a pre-keep-alive link with the previously paired Bluetooth headset to form a dual virtual channel; Multi-source command arbitration steps: Listen for multi-source trigger commands within the system, and intercept commands and lock the state machine based on a preset multi-level priority arbitration mechanism. Only when the system is idle and no high-priority commands are executed will the mode switching command for the audio private transmission function be responded to. Dual-mode switching and timing control steps: When responding to the command to enable the audio privacy transmission function, the audio privacy transmission function is strongly bound to the Bluetooth host mode based on the hardware state machine, the pre-protection link is activated to complete the seamless connection, and the audio buffer lock, power amplifier hardware mute, audio route switching and audio stream recovery are executed in sequence according to the preset irreversible timing sequence. Dual-partition storage isolation steps: During the master-slave dual-mode switching process, based on the physically isolated dual-partition storage mechanism, the fixed storage partition and the erasable temporary storage partition are called respectively to physically isolate the pairing information between the first host device and the Bluetooth headset.

[0007] According to the above technical solution, the multi-level priority arbitration mechanism adopted in the multi-source instruction arbitration step is set in order of priority from high to low as follows: hardware-level interrupts triggered by physical buttons, kernel-level system restart instructions, and application-layer software instructions issued by serial port configuration file protocol.

[0008] According to the above technical solution, the strong binding of the audio private transmission function with the Bluetooth master mode based on the hardware state machine specifically means: defining a global state register in the Bluetooth firmware, sharing the same register bit between the on / off state of the audio private transmission function and the Bluetooth master / slave mode state, and forcibly switching the states of the two through hardware configuration to prevent independent modification of the interface.

[0009] According to the above technical solution, in the dual-mode switching and timing control steps, the preset irreversible timing specifically includes the following control actions, and each step must wait for the previous hardware interrupt to complete before execution: Lock the audio input buffer and pause audio playback; By pulling low the power enable pin of the power amplifier module, the speaker is turned off at the hardware level. Switch the output routing of the audio codec module from the speaker channel to the host mode channel of the dual-mode Bluetooth module; Switch the dual-mode Bluetooth module from slave mode to master mode; Unlock the audio input buffer and resume audio streaming to Bluetooth headphones.

[0010] According to the above technical solution, the physically isolated dual-partition storage mechanism includes a read-only first hardware address range and an erasable second hardware address range; the fixed storage partition corresponds to the first hardware address range and permanently stores the pairing information of the first host device; the temporary storage partition corresponds to the second hardware address range and is used only to store the pairing information of the Bluetooth headset, and is configured to be automatically cleared when a system restart or hardware reset command is received.

[0011] According to the above technical solution, in the step of establishing a pre-keeping live link, the system sends broadcast heartbeat packets in the background at a preset period through the secondary channel to maintain authentication information, without transmitting audio data; when switching to Bluetooth host mode in response to the start command, the authentication information is directly reused to establish an advanced audio distribution profile connection with the Bluetooth headset.

[0012] According to the above technical solution, it also includes a full-scenario abnormal closed-loop rollback step: if any abnormal situation is detected, such as audio privacy transmission function activation timeout, Bluetooth headset abnormal disconnection timeout, mode switching timeout, or system low battery state, a hardware forced reset will be automatically triggered: the dual-mode Bluetooth module will be switched back to slave mode, the temporary storage partition will be cleared, and the power supply of the power amplifier module will be increased by hardware to restore the speaker's external playback.

[0013] A Bluetooth speaker system based on Bluetooth master-slave dual-mode switching, the system includes: The main control module is used for instruction parsing, timing control, and state machine management. Dual-mode Bluetooth module, which communicates with the Android main control module, supports advanced audio distribution profile master-slave dual roles and low-power Bluetooth communication, used to establish dual virtual channels and execute mode switching; The dual-partition storage module communicates with the Android main control module and is physically divided into a fixed storage partition and a temporary storage partition. The power amplifier control module is equipped with a hardware-level enable pin, which receives instructions from the Android main control module to execute precise mute or on / off control of the speaker. The audio codec module connects to the Android main control module and the dual-mode Bluetooth module, and is used to allocate the output channel of the audio stream according to the routing switching command.

[0014] According to the above technical solution, the system also includes a play / pause button module. The communication end of the button module is directly connected to the hardware interrupt pin of the Android main control module. When a long press operation of a preset duration is detected, a hardware interrupt signal with the highest system priority is triggered to the Android main control module.

[0015] According to the above technical solution, after receiving a hardware interrupt signal, the Android main control module is configured to unconditionally suspend the current application layer and kernel layer processes, send a reset command to the dual-mode Bluetooth module to disconnect all current links, force it to be set to slave mode, and clear the temporary storage partition in the dual-partition storage module to perform emergency recovery.

[0016] Compared with the prior art, the present invention has the following beneficial effects: This invention achieves seamless switching between master and slave modes through dual virtual channel pre-keep-alive technology, keeping the mode switching time within 300ms and the audio pause duration within 100ms, resulting in a seamless user experience with zero audio interruption. Simultaneously, by introducing a three-level hardware and software instruction arbitration mechanism and state machine strong binding logic, this invention completely solves the instruction conflict problem when multiple control sources are running concurrently, ensuring a high degree of consistency in system state and operating mode. Through a dual-partition physical isolation storage architecture, this invention achieves complete isolation and zero interference of master-slave device pairing information, eliminating the tedious operation of repeatedly re-pairing devices for users. Furthermore, through irreversible hardware-level timing control accurate to 1ms, this invention achieves absolute synchronization between amplifier mute and audio routing switching, fundamentally preventing privacy leaks and experience gaps caused by dual audio output or complete silence.

[0017] This invention also establishes an automatic closed-loop fallback mechanism covering all scenarios such as connection timeout, disconnection, and low battery, combined with a long-press hardware reset function with the highest system priority, giving the system extremely high fault tolerance and emergency repair capabilities, completely preventing users from falling into a silent deadlock; in addition, this invention controls the background heartbeat standby power consumption to below 1mA through a Bluetooth Low Energy (BLE) pre-keep-alive link, which improves the overall battery life of the device in host mode by more than 20% compared with the traditional continuous scanning solution. Attached Figure Description

[0018] Figure 1 This is a flowchart of the control method of the present invention. Detailed Implementation

[0019] 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, and 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.

[0020] Example 1 like Figure 1As shown, this embodiment provides a Bluetooth speaker system based on Bluetooth master-slave dual-mode switching. The hardware of this invention relies on an ARM architecture SoC running the Android operating system as the main control module, and coordinates with various peripheral modules through a standard high-speed hardware bus.

[0021] Furthermore, in addition to HCI command interaction via the UART bus, the main control module and the dual-mode Bluetooth module employ a system-level DMA (Direct Memory Access) controller for audio data stream transmission. Specifically, this DMA controller is configured for unidirectional continuous transmission mode, with its source address mapped to the audio transmission ring buffer in the SoC's external DDR SDRAM, and its destination address fixed to the TX data register of the I2S bus controller. The entire transmission process is controlled by the hardware DMA request signal of the I2S controller for flow control matching. Preferably, through DMA transfer, the system completely frees the CPU from interrupts involving byte-by-byte audio data copying, significantly reducing CPU load and effectively avoiding the risk of I2S FIFO underflow caused by CPU scheduling latency.

[0022] Furthermore, the system's audio codec module embeds an ASRC (Asynchronous Sample Rate Converter) unit. Specifically, after the Bluetooth module and the headphones complete the codec capability negotiation at the A2DP protocol layer, the main control module extracts the negotiated target sampling rate and configures the ASRC's frequency division coefficient register accordingly. Preferably, the ASRC effectively suppresses sampling rate mismatch distortion caused by the asynchronous operation of the local audio source clock and the Bluetooth transmission clock through interpolation and decimation algorithms in the digital domain. Specifically, the system's dual-partition storage module uses a SPINANDFlash chip.

[0023] Furthermore, for the slave fixed partition of the storage system's core configuration parameters, the underlying file system forcibly enables the hardware ECC module. This mechanism can automatically detect and correct single-bit errors in the storage medium, and throw an exception when multi-bit errors are detected to ensure key integrity. Preferably, for the frequently updated host temporary partition, the underlying driver mounts standard bad block management and wear leveling algorithms. Considering the objective time-consuming nature of physical block erasure, this erasure action is designed to be performed by an asynchronous background thread after the system is completely idle or restarted, to avoid blocking the system's real-time audio services.

[0024] Example 2 This embodiment also provides an audio control method based on Bluetooth master-slave dual-mode switching that runs on the above-mentioned hardware system, in order to solve the problems of underlying authentication, memory scheduling and abnormal security rollback during mode switching.

[0025] Furthermore, in the construction of the dual virtual channels, the system's underlying layer utilizes the Cross-Transmission Key Derivation (CTKD) function of the BLE protocol stack standard. Specifically, in slave mode, for paired devices with established trust relationships, the master control module uses the long-term key of the BLE link to derive the classic Bluetooth A2DP link key within a secure operating environment through encryption key derivation functions such as AES-CMAC. Preferably, when a master mode switch is triggered, the master control module directly writes the link key into the secure RAM area of ​​the Bluetooth baseband controller by calling the Bluetooth chip manufacturer's specific HCI extended command, thereby bypassing the time-consuming paging scan phase while ensuring security boundaries, and hard-compressing the reconnection time to within 300ms. Specifically, during the audio routing transition phase of mode switching, the system memory management module adopts a standard ping-pong double buffering mechanism.

[0026] Furthermore, the buffer size is preset to meet the maximum audio latency (e.g., configured to hold at least 100ms of PCM data). When a switch is triggered, the main control module acquires a mutex lock to block the output pointer of the upper-layer audio decoding thread. At this time, the underlying I2S DMA read pointer automatically switches from the exhausted Ping area to the full Pong area to maintain output. Preferably, once the Bluetooth mode state machine register completes its toggle, the main control module releases the mutex lock, and the decoding thread continues to write to the free buffer, thereby achieving a smooth transition of the audio stream without causing a kernel deadlock. Specifically, in response to unpredictable software deadlocks or protocol stack crashes, the system is configured to use a physical button to trigger a non-maskable interrupt (NMI) as a final safety measure.

[0027] Furthermore, since the interrupt handler must adhere to the fundamental rule of fast entry and exit, when the interrupt is triggered, the service routine is absolutely prohibited from calling Flash erase operations that may cause blocking. Preferably, the service routine only executes three atomic actions in sequence: pulling the power amplifier control GPIO pin low to achieve hardware power-off mute, writing the emergency reset flag bit into the RTC backup register, and actively triggering the hardware watchdog reset instruction.

[0028] Furthermore, after the system completes the instantaneous hardware reboot, the bootloader reads the flag in the security context and then calmly executes the time-consuming Flash temporary partition erasure and state reset process, thereby ensuring the absolute physical reliability of the system's escape mechanism.

[0029] The following section, using specific embodiments, details the deep integration and textual transformation of the mathematical model in the original solution according to your requirements. This section removes the direct nesting of conventional physical formulas, describing the basic implementation process entirely through the coherent language of patent writing standards. It retains only two original mathematical analytical formulas derived and integrated specifically to address the technical pain points of this invention (i.e., seamless audio overflow prevention and ultra-low power agile connection), ensuring that the specification combines the rigor of legal text with a high degree of professionalism in its underlying logic.

[0030] Example 3 This embodiment, based on the ping-pong double buffering mechanism of Embodiment 2, provides a dynamic buffer overflow prevention and recovery mechanism based on underlying logic evaluation. It aims to solve the data backlog problem during routing switching through software-level conditional admission and nonlinear control. Furthermore, the system kernel abandons the traditional bit rate integral calculation formula. Before responding to a switching command, it directly polls the remaining free physical capacity of the current buffer and compares it with the theoretically generated total number of audio frames within the factory-predefined hardware routing switching limit delay using Boolean logic. Only when the absolute remaining capacity is greater than the theoretical increment during the switching period is the underlying state machine switching action allowed, thus avoiding complex floating-point arithmetic delays at the code execution level.

[0031] Furthermore, after completing the switching and restoring the data stream output, to address the issue of smoothly consuming the backlogged data in the buffer, this embodiment differs from the simple and crude fixed-rate acceleration in existing technologies. It innovatively employs a dynamic time-domain compression compensation mechanism based on nonlinear variable gain ratio control. Specifically, the main control module calls the phase vocoder algorithm at the DSP layer. While maintaining the pitch as constant as possible within the algorithm's capabilities, it calculates the dynamic time scaling factor using the invention's unique nonlinear saturation control equation. To achieve adaptive acceleration of audio stream consumption: Specifically, in this unique model that differs from conventional linear control, the unit for all capacity variables is uniformly defined as bytes. The actual number of backlogged bytes in the buffer at the moment the stream resumes; The total physical capacity of a single-sided ping-pong buffer zone; To ensure a steady-state safety level sufficient to prevent underload overflow in I2SDMA (e.g., 13824 bytes configured for 48kHz / 16bit dual-channel). Furthermore, the core technical feature of this formula lies in the introduction of a gain constant... Modulated dangerous approximation rate penalty When the backlog approaches the physical limit, the fractional nonlinearity surges, forcing the system to protect the limit by closely approaching the physical threshold. The data is consumed at its maximum rate; as the water level recedes, the scaling factor smoothly and non-linearly decays to 1.0. Preferably, this negative feedback equation that deeply binds the physical buffer water level can silently pull the audio timing back to a synchronized state without manual intervention and without system crashes.

[0032] Example 4 Specifically, this embodiment, based on the BLE keep-alive mechanism of Embodiment 1, provides an optimal scheduling algorithm that deeply integrates hardware physical constraints. Existing technologies typically employ fixed heartbeat cycles for polling, which easily leads to the dilemma of excessive power consumption or severe wake-up timeouts. Furthermore, in this embodiment, the main control module constructs a mathematical convex optimization logic model at the underlying level to evaluate the overall system cost. This logic model jointly constrains the absolute power loss of the battery with the delay penalty caused by spatial signal attenuation, and directly parses the globally optimal solution of this logic model through the underlying kernel, completely replacing the traditional lookup table method or firmware hard-coded configuration.

[0033] Preferably, the main control module directly extracts the real-time battery status and the spatial signal status of the RF baseband from the power management IC, and periodically calculates and sends the actual underlying polling interval to the baseband through the following highly integrated adaptive limiting equation. : Specifically, in the integrated driver layer control formula, the fractions within the square root constitute the core adaptive engine of the system. This is a dimensionless ratio of the current remaining battery capacity. For receiving signal strength indication, To maintain the link's continuity, a low-level threshold is set at the underlying level. Furthermore, and These are the power consumption weighting constant and the delay weighting constant, which are fixed in the system's factory acoustic and RF joint calibration, respectively. This is the environmental space signal attenuation compensation coefficient.

[0034] Preferably, the originality and technical effectiveness of this formula are reflected in its self-consistent physical mapping logic: when the headphones are close to the speaker, Increased trigger index items The exponential increase in the denominator forces the calculated polling interval to collapse rapidly, thus giving the device the ability to instantly enter a high-frequency, agile listening state; conversely, when the battery power... As the depletion approaches the red line, the denominator shrinks drastically, causing the calculation result to lengthen and enter deep dormancy. Furthermore, to prevent physical disconnection that might be caused by purely mathematical extrema under extreme conditions, the outermost layer of the formula is nested with a maximum valid timeout window based on the protocol stack. The physical truncation logic (min function) enables an absolute physical closed loop of Bluetooth connection agility, extreme battery life and bottom-level link disconnection prevention at the underlying code level with extremely low CPU computing power overhead.

[0035] It should be noted that, in this document, relational terms such as "first" and "second" are used only to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "include," "contain," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus.

[0036] Finally, it should be noted that the above descriptions are merely preferred embodiments of the present invention and are not intended to limit the present invention. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art can still modify the technical solutions described in the foregoing embodiments or make equivalent substitutions for some of the technical features. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A method for controlling the private transmission of audio based on Bluetooth master-slave dual-mode switching, characterized in that: For use in Bluetooth speakers, the control methods include: Dual virtual channel establishment steps: In the default Bluetooth slave mode, maintain a standard audio connection with the first host device, and at the same time start low power Bluetooth scanning and establish a pre-keep-alive link with the previously paired Bluetooth headset to form a dual virtual channel; Multi-source command arbitration steps: Listen for multi-source trigger commands within the system, and intercept commands and lock the state machine based on a preset multi-level priority arbitration mechanism. Only when the system is idle and no high-priority commands are executed will the mode switching command for the audio private transmission function be responded to. Dual-mode switching and timing control steps: When responding to the command to enable the audio privacy transmission function, the audio privacy transmission function is strongly bound to the Bluetooth host mode based on the hardware state machine, the pre-protection link is activated to complete the seamless connection, and the audio buffer lock, power amplifier hardware mute, audio route switching and audio stream recovery are executed in sequence according to the preset irreversible timing sequence. Dual-partition storage isolation steps: During the master-slave dual-mode switching process, based on the physically isolated dual-partition storage mechanism, the fixed storage partition and the erasable temporary storage partition are called respectively to physically isolate the pairing information between the first host device and the Bluetooth headset.

2. The audio privacy transmission control method based on Bluetooth master-slave dual-mode switching according to claim 1, characterized in that: The multi-level priority arbitration mechanism used in the multi-source instruction arbitration step is set in order of priority from high to low as follows: hardware-level interrupts triggered by physical buttons, kernel-level system restart instructions, and application-layer software instructions issued by the serial port configuration file protocol.

3. The audio privacy transmission control method based on Bluetooth master-slave dual-mode switching according to claim 1, characterized in that: The hardware state machine-based strong binding of the audio privacy transmission function with the Bluetooth master mode specifically refers to defining a global state register in the Bluetooth firmware, sharing the same register bit between the on / off state of the audio privacy transmission function and the Bluetooth master / slave mode state, and forcibly configuring the synchronous switching of the two states through hardware configuration to prevent independent modification of the interface.

4. The audio privacy transmission control method based on Bluetooth master-slave dual-mode switching according to claim 1, characterized in that: In the dual-mode switching and timing control steps, the preset irreversible timing specifically includes the following control actions, and each step must wait for the hardware interrupt of the previous step to complete before execution: Lock the audio input buffer and pause audio playback; By pulling low the power enable pin of the power amplifier module, the speaker is turned off at the hardware level. Switch the output routing of the audio codec module from the speaker channel to the host mode channel of the dual-mode Bluetooth module; Switch the dual-mode Bluetooth module from slave mode to master mode; Unlock the audio input buffer and resume audio streaming to Bluetooth headphones.

5. The audio privacy transmission control method based on Bluetooth master-slave dual-mode switching according to claim 1, characterized in that: The physically isolated dual-partition storage mechanism includes a read-only first hardware address range and an erasable second hardware address range; the fixed storage partition corresponds to the first hardware address range and permanently stores the pairing information of the first host device; The temporary storage partition corresponds to the second hardware address range and is used only to store pairing information for Bluetooth headsets. It is configured to be automatically cleared when a system restart or hardware reset command is received.

6. The audio privacy transmission control method based on Bluetooth master-slave dual-mode switching according to claim 1, characterized in that: In the process of establishing a pre-alive link, the system sends broadcast heartbeat packets in the background at a preset period through a secondary channel to maintain authentication information, without transmitting audio data; when switching to Bluetooth host mode in response to the start command, it directly reuses the authentication information to establish an advanced audio distribution profile connection with the Bluetooth headset.

7. A method for controlling the private audio transmission based on Bluetooth master-slave dual-mode switching according to any one of claims 1 to 6, characterized in that: It also includes a full-scene abnormal closed-loop rollback step: if any of the following abnormal situations are detected, such as audio privacy transmission function activation timeout, Bluetooth headset abnormal disconnection timeout, mode switching timeout, or system low battery state, a hardware forced reset will be automatically triggered: the dual-mode Bluetooth module will be switched back to slave mode, the temporary storage partition will be cleared, and the power supply of the power amplifier module will be increased by hardware to restore the speaker's external output.

8. A Bluetooth speaker system based on Bluetooth master-slave dual-mode switching, used to execute the audio privacy transmission control method as described in any one of claims 1 to 7, characterized in that: The system includes: The main control module is used for instruction parsing, timing control, and state machine management. Dual-mode Bluetooth module, which communicates with the Android main control module, supports advanced audio distribution profile master-slave dual roles and low-power Bluetooth communication, used to establish dual virtual channels and execute mode switching; The dual-partition storage module communicates with the Android main control module and is physically divided into a fixed storage partition and a temporary storage partition. The power amplifier control module is equipped with a hardware-level enable pin, which receives instructions from the Android main control module to execute precise mute or on / off control of the speaker. The audio codec module connects to the Android main control module and the dual-mode Bluetooth module, and is used to allocate the output channel of the audio stream according to the routing switching command.

9. A Bluetooth speaker system based on Bluetooth master-slave dual-mode switching according to claim 8, characterized in that: The system also includes a play / pause button module, whose communication terminal is directly connected to the hardware interrupt pin of the Android main control module; when a long press operation of a preset duration is detected, a hardware interrupt signal with the highest system priority is triggered to the Android main control module.

10. A Bluetooth speaker system based on Bluetooth master-slave dual-mode switching according to claim 9, characterized in that, Its features are: After receiving a hardware interrupt signal, the Android main control module is configured to unconditionally suspend the current application layer and kernel layer processes, send a reset command to the dual-mode Bluetooth module to disconnect all current links, force it to be set to slave mode, and clear the temporary storage partition in the dual-partition storage module to perform emergency recovery.

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