Power-off detection method, audio playing device, audio system and storage medium

Abstract

The application provides a power-off detection method, an audio playing device, an audio system and a storage medium, and relates to the field of audio devices. The power-off detection method is applied to an audio playing device, and comprises the following steps: detecting a first signal packet in a playing process of audio data; an audio source device is connected with the audio playing device through a USB interface, and the audio source device supplies power to the audio playing device through the USB interface; the first signal packet is a signal packet periodically sent by the audio source device based on a USB protocol; if a next first signal packet is not detected within a first preset time length, it is determined that the audio playing device is powered off; the first preset time length is longer than a cycle time length of sending the first signal packet, and the first preset time length is shorter than a preset power-off time length of the audio playing device.

Description

Technical Field

[0001] This application relates to the field of audio devices, and more specifically, to a power failure detection method, an audio playback device, an audio system, and a storage medium. Background Technology

[0002] USB (Universal Serial Bus) audio playback devices, such as USB headphones and USB speakers, can connect to audio source devices via USB to receive and play audio from the source devices.

[0003] The USB port includes a power connector, allowing the audio source device to power the USB audio playback device. If the USB audio playback device is unplugged from the audio source device while the audio source device is outputting audio data, audio output will stop, and the audio source device will cease supplying power to the USB audio playback device. However, even after power is cut off, a residual charge may remain at the USB port of the USB audio playback device. This residual charge may cause a popping sound (or "crackling sound") in the headphones, affecting the user experience.

[0004] Therefore, it is necessary to promptly detect whether the USB audio playback device has been unplugged from the audio source device and powered off, so as to promptly de-energize all circuits after power failure and reduce pop-up noise. Currently, an additional power-down detection circuit is added to the circuitry at the interface of the USB audio playback device, but this adds extra chip space and increases cost. Summary of the Invention

[0005] In view of this, this application aims to provide a power failure detection method, an audio playback device, an audio system, and a storage medium to reduce the chip area required for power failure detection.

[0006] In a first aspect, embodiments of this application provide a power failure detection method applied to an audio playback device. The power failure detection method includes: detecting a first signal packet during the playback of audio data; an audio source device is connected to the audio playback device via a USB interface, and the audio source device supplies power to the audio playback device via the USB interface; the first signal packet is a signal packet periodically emitted by the audio source device based on the USB protocol; if no next first signal packet is detected within a first preset duration, it is determined that the audio playback device is powered off; the first preset duration is longer than the period of sending the first signal packet, and the first preset duration is shorter than a preset power failure duration of the audio playback device.

[0007] In this embodiment, the USB protocol specifies that the first signal packet is sent periodically. If the first signal packet is lost, it may be due to a power outage. Therefore, the first signal packet can be detected within a first preset time period to determine whether the first signal packet is lost, thereby determining whether a power outage has occurred. Since the first signal packet is sent and detected periodically by the USB protocol, it does not affect the transmission of audio data and does not require additional circuitry. Thus, the chip area required for power outage detection of the USB interface can be effectively reduced.

[0008] In one embodiment, the audio playback device includes a timer program configured to restart timing in response to the detection of the first signal packet; the timer program is also configured with a first preset duration; after the first signal packet is detected, the power failure detection method further includes: if it is determined that the timing of the timer program is greater than the first preset duration, then it is determined that no next first signal packet has been detected within the first preset duration.

[0009] In this embodiment, a timer program can be used to implement timing after the first signal packet is detected. By configuring the timer as a program, the timer program can be applied to devices in the audio playback device that can run programs. Therefore, there is no need to set up additional circuitry for timing, reducing the chip area required for power-off detection.

[0010] In one embodiment, before detecting the first signal packet, the method further includes: determining the first preset duration according to the speed mode in the USB protocol used by the audio playback device; the period duration for sending the first signal packet is different for different speed modes.

[0011] The USB protocol has different speed modes, and the transmission rates corresponding to different speed modes are inconsistent. This results in inconsistent transmission frequencies of the first signal packets. In this embodiment, a first preset duration is determined according to the speed mode of the USB protocol supported by the audio playback device to reduce the situation where the first signal packet is lost and not detected, and to detect power failure as soon as possible for corresponding processing, thereby reducing the generation of POP sound.

[0012] In one embodiment, the first signal packet is an SOF packet (frame header packet).

[0013] In the USB protocol, all high-speed and full-speed functions send and receive SOF packets. SOF packets and data packets are sent in a time-division multiplexing manner. In the embodiments of this application, it can be determined whether data is being transmitted between the audio playback device and the audio source device by detecting SOF packets, thereby determining whether there is a power outage. Furthermore, the sending of SOF packets will not cause any functional response and will not affect the normal playback of the audio playback device.

[0014] In one embodiment, after determining that the audio playback device is powered off, the method further includes: disabling the audio data output; and controlling the circuits in the audio playback device that output the audio data to power off.

[0015] In this embodiment of the application, after a power outage is detected, the output of audio data and the circuits controlling the output of audio data are promptly disabled, which can effectively reduce residual charge and reduce the generation of pop noise.

[0016] In one embodiment, after determining that the internal circuits of the audio playback device have lost power, the method further includes: continuing to detect the first signal packet; if the first signal packet is detected within a second preset duration, then restoring the power supply to the internal circuits of the audio playback device and restoring the output of the audio data; wherein: the second preset duration is located between the first preset duration and the period duration of sending the first signal packet; the sum of the second preset duration and the first preset duration is less than the preset power-off duration of the audio playback device.

[0017] In this embodiment, after a power outage, the first signal packet is still detected. If the first signal packet is detected after a second preset time, the power supply and audio data output are restored. This reduces the possibility of false triggering during power outage detection and allows the audio data to be played normally.

[0018] Secondly, this application provides an audio playback device, including: a USB interface for connecting to an audio source device to receive audio data sent by the audio source device, a first signal packet periodically sent based on the USB protocol, and power provided by the audio source device; a USB module connected to the USB interface, the USB module being used to obtain the first signal packet from the USB interface; the USB module is further configured to perform the power failure detection method as described in any of the first aspects.

[0019] In one embodiment, the audio playback device further includes: a processor connected to the USB module, the processor being configured with a timer program; the timer program being configured to restart timing in response to the detection of the first signal packet; the timer program being configured with the first preset duration.

[0020] In this embodiment, timing is achieved by configuring a timer program in the processor, eliminating the need for an additional timing circuit and reducing the chip area required for power failure detection.

[0021] In one embodiment, the audio playback device is headphones.

[0022] Thirdly, embodiments of this application provide an audio system, including: a sound source device; and an audio playback device as described in the second aspect, connected to the sound source device via the USB interface.

[0023] Fourthly, embodiments of this application provide a storage medium storing instructions that can be executed by a USB module to implement the power failure detection method as described in any of the first aspects. Attached Figure Description

[0024] To more clearly illustrate the technical solutions of the embodiments of this application, the accompanying drawings used in the embodiments of this application will be briefly introduced below. It should be understood that the following drawings only show some embodiments of this application and should not be regarded as a limitation of the scope. For those skilled in the art, other related drawings can be obtained based on these drawings without creative effort.

[0025] Figure 1 This application provides a schematic diagram of the structure of an audio playback device;

[0026] Figure 2 An extended schematic diagram of an audio playback device is provided in this application embodiment;

[0027] Figure 3 This application provides a flowchart of an audio playback method;

[0028] Figure 4 This is a schematic diagram illustrating a first preset duration in one embodiment of the present application;

[0029] Figure 5 This is a schematic diagram illustrating a second preset duration in one embodiment of this application;

[0030] Figure 6 This is a schematic diagram illustrating accidental trigger recovery in one embodiment of this application;

[0031] Figure 7 This is a schematic diagram of an audio playback system provided in one embodiment of this application.

[0032] Icons: Audio playback device 100; USB interface 110; USB module 120; Processor 130; Audio subsystem digital module 141; Audio subsystem analog module 142; Headphones 150; Audio source device 200. Detailed Implementation

[0033] To make the objectives, technical solutions, and advantages of this application clearer, the following detailed description is provided in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the scope of this application.

[0034] Please see Figure 1 , Figure 1 This is a schematic diagram of the structure of an audio playback device provided in an embodiment of this application. The audio playback device 100 includes: a USB interface 110 and a USB module 120.

[0035] USB interface 110 is used to connect audio source devices.

[0036] In this embodiment, the USB interface 110 can be any common USB interface, such as Type-C, Type-A, etc., or different versions of USB interfaces, such as USB 2.0, USB 1.1, USB 3.0, etc., which will not be elaborated here.

[0037] The USB interface 110 includes a data cable and a power cable. After connecting the USB interface to a device, data can be transmitted via the data cable. In this embodiment, the USB interface is connected to an audio source device, allowing audio data to be transmitted via the data cable. Connecting the USB interface to a power supply device, such as a computer, mobile phone, or USB power supply, allows power to be supplied to the audio playback device via the power cable. Specific details about the USB interface can be found in existing technologies and will not be elaborated upon here.

[0038] USB module 120 is connected to USB interface 110.

[0039] USB module 120 is used to implement USB physical layer electrical signal conversion and communication and control of underlying protocols. The specific principles can be found in existing USB communication modules and will not be elaborated here. In the embodiments of this application, USB module 120 is configured with a program that allows it to acquire data from USB interface 110 and implement the power failure detection method provided in this application.

[0040] Furthermore, the above only describes some modules of the audio playback device 100. In real-world scenarios, other modules may also be configured within the audio playback device. Please refer to [link / reference]. Figure 2 , Figure 2 This is an extended schematic diagram of an audio playback device provided in this application. Figure 2 This example uses headphones as the audio playback device.

[0041] The audio playback device 100 may also include a processor 130, which is connected to the USB module 120. The processor can be various types of CPUs (Central Processing Units), MCUs (Microcontroller Units), etc., used to control and process data in various circuits and modules within the audio playback device 100.

[0042] In embodiments of this application, the processor 130 is configured with a timer program that can receive signals from the USB module 120 to start and reset timing. The timer program is configured to restart timing in response to the detection of a first signal packet.

[0043] The audio playback device may also include an audio subsystem digital module 141 and an audio subsystem analog module 142, which are used to convert audio data from digital to analog and output it to the playback end for playback, or to convert the data collected by the headphone microphone and then forward it to the device connected to the USB interface 110.

[0044] The above are merely examples; the audio playback device 100 may also include circuits and modules with other functions, which will not be elaborated here.

[0045] Next, we will elaborate on the power failure detection method performed by the USB module 120.

[0046] Please see Figure 3 , Figure 3 A flowchart illustrating a power outage detection method according to an embodiment of this application. The power outage detection method includes:

[0047] S110 detects the first signal packet during the playback of audio data.

[0048] The audio source device is connected to the audio playback device 100 via USB interface 110. The audio source device can supply power to the audio playback device 100 via the power cable in USB interface 110, and can also transmit audio data and other data via the data cable. If USB interface 110 is unplugged from the audio source device, the audio source device cannot supply power to the audio playback device 100, and the data cable cannot transmit data either.

[0049] Furthermore, according to the existing USB protocol's definition of each connecting cable in the USB interface 110, the power cable is 1.5mm longer than the data cable, and the data cable disconnects before the power cable. If the audio playback device is powered off, data transmission will inevitably fail.

[0050] Therefore, in the embodiments of this application, whether a power outage has occurred can be determined by whether the USB interface 110 can receive data normally. If the USB interface 110 cannot receive data normally, packet loss may occur. Therefore, the audio source device can periodically send a signal packet with identification characteristics, namely a first signal packet, to the USB interface 110. The audio playback device 100 detects whether it receives the first signal packet, thereby determining whether a power outage has occurred.

[0051] In this embodiment, the first signal packet can be a model packet with identification information periodically emitted by the audio source device, or it can be a signal packet periodically emitted by the audio source device based on the USB protocol.

[0052] When the audio source device transmits data via USB, the transmitted data consists of SOF packets, Token packets (command packets), Data packets (data packets), and Handshake packets (handshake packets), and is periodically sent to the audio playback device 100. In this case, SOF packets, Token packets, and Handshake packets can be used as the first signal packets, or identification information can be set in the Data packets to use the Data packets as the first signal packets.

[0053] In some embodiments, the SOF packet may be selected as the first signal packet.

[0054] When an SOF packet is detected, the USB module 120 recognizes that it has received a time-dependent data frame. During normal data transmission, SOF packets are configured to be sent at a certain frequency; therefore, SOF packets can serve as the first data packet. Furthermore, SOF packets do not elicit any functional responses and do not affect the normal operation of the audio playback device 100.

[0055] S120, if no next first signal packet is detected within the first preset time period, determine that the audio playback device is powered off.

[0056] In this embodiment, the first signal packet is a signal packet that the audio source device periodically sends to the audio playback device 100 based on the USB protocol. If the first signal packet is lost, that is, if the next first signal packet is not detected after the transmission period of the first signal packet has expired, the USB interface 110 may be unplugged from the audio source device, and the audio source device will no longer supply power to the audio playback device 100, that is, a power outage will occur.

[0057] Since the audio source device sends the first signal packet to the audio playback device 100 periodically, the first preset duration should be greater than the period duration of sending the first signal packet.

[0058] Furthermore, after the USB interface 110 is unplugged from the audio source device, the remaining power will continue to power the audio playback device 100. Therefore, there is approximately 2 to 3 milliseconds between unplugging the USB interface 110 and the actual power-off. Power-off detection should be completed before the actual power-off detection to allow for appropriate handling. Therefore, the time required for the actual power-off can be set as a preset power-off duration, and the first preset duration can be configured to be shorter than this preset power-off duration. Additionally, the power cable of the USB interface 110 is longer than the data cable, allowing more time to determine whether the first signal packet has been received, thus allowing more time for subsequent handling.

[0059] In some embodiments, the first preset duration can be determined based on the speed mode in the USB protocol used by the audio playback device 100.

[0060] The speed modes include Full Speed ​​mode and High Speed ​​mode. The interval period for sending the first signal packet is different for different speed modes. For example, the interval for sending SOF packets in Full Speed ​​mode is 1ms, while the interval for sending SOF packets in High Speed ​​mode is as low as 125us.

[0061] Different versions of the USB protocol have different periods for sending the first signal packet. If the first preset duration is too long, far exceeding the period for sending the first signal packet, multiple packet losses may occur, making power failure detection untimely. Therefore, the first preset duration can be determined according to the speed mode of the USB protocol used when the audio playback device 100 and the audio source device transmit data via USB.

[0062] In some embodiments, the first preset duration is greater than the period duration of transmitting the first signal packet, and the first preset duration is greater than less than twice the period duration of transmitting the first signal packet.

[0063] In some embodiments, a timer program can be set in the audio playback device 100. The timer program can be set in the processor to record the time when the first signal packet is received.

[0064] In this embodiment, the timer program can be configured to restart timing in response to the USB module 120 detecting the first signal packet. For example, the timer program's response to the first signal packet could be that the USB module 120 generates an interrupt signal after detecting the first signal packet and sends the interrupt signal to the processor. After receiving the first signal packet, the processor triggers the timer program to start timing from 0.

[0065] In this embodiment, a timer program can be used to record the time when the first signal packet is received. If the timer program's countdown is greater than a first preset duration, it can be determined that no next first signal packet was detected within the first preset duration. Conversely, if the timer program's countdown reaches the first preset value, it can be determined that the first signal packet was lost, and a power outage may occur, allowing for subsequent processing.

[0066] Please see Figure 4 , Figure 4 This is a schematic diagram of a first preset duration provided in one embodiment of the present application, wherein SOF is a first signal packet, 1ms is the transmission period of SOF, and 1.5ms is the first preset duration.

[0067] like Figure 4As shown, when the USB module 120 detects an SOF packet, the timer program starts timing. If the next SOF packet is received within 1.5ms, the existing timer is cleared and restarted. This process continues. If no SOF packet is received, the timer program does not clear the timer; after 1.5ms, it is confirmed that the first signal packet was lost, and a power outage may occur. The SOF packet interface and the timer program do not affect the normal transmission of data packets. Therefore, power outage detection is achieved without affecting normal audio playback.

[0068] In some embodiments, after determining that the audio playback device 100 is powered off, the power-off detection method may further include: disabling audio data output; and controlling the power-off of each circuit in the audio playback device 100 that outputs audio data.

[0069] like Figure 5 As shown, when the timer program reaches 1.5ms, audio data output is disabled and power is cut off. After detecting a power failure, timely action is required to reduce the likelihood of pop-up sounds. In this embodiment, audio data output can be disabled first, and the circuits in the audio playback device 100 that output audio data can be powered off to prevent residual power from supplying playback devices such as speakers and headphones 150, thereby reducing the possibility of pop-up sounds. For example, the circuit that outputs audio data includes an audio subsystem analog module 142, and the audio subsystem analog module 142 can be powered off.

[0070] In some scenarios, the loss of the first signal packet may not be caused by a power outage, but it still triggers the prohibition of audio data output and power failure. For such false triggering situations, in some embodiments of this application, after the power is cut off to each circuit inside the audio playback device 100, the first signal packet can still be detected. If the first signal packet is detected within a second preset time period, the power supply to each circuit inside the audio playback device 100 is restored and the output of audio data is restored.

[0071] In this embodiment, the second preset duration is located between the first preset duration and the period duration of sending the first signal packet. If the first preset duration is 1.5ms and the period duration of sending the first signal packet is 1ms, then the second preset duration is between 1ms and 1.5ms, and can be equal to 1ms or 1.5ms.

[0072] In this embodiment, the sum of the second preset duration and the first preset duration is less than the preset power-off duration of the audio playback device 100. As mentioned above, after the USB interface 110 is unplugged, the residual power can still continue to supply power, and the time for which power can be supplied is the preset power-off duration. The false trigger detection should be completed before the power is cut off. Therefore, the sum of the second preset duration and the first preset duration is less than the preset power-off duration.

[0073] For example, such as Figure 5 As shown, the second preset duration is 1ms. When the SOF is lost, the timer program triggers a power-off and disables audio data output after 1.5ms. At this time, the timer program can start timing again and continue to check for the first signal packet. If this timing exceeds the second preset duration of 1ms, a power-off is determined. Conversely, if... Figure 6 As shown, if the timing does not exceed the second preset duration of 1ms, that is, if the first signal packet is received within 1ms, then power supply and audio data output are restored.

[0074] Therefore, by configuring a second preset duration, the possibility of audio playback abnormalities caused by accidental triggering can be effectively reduced.

[0075] In some embodiments, the timing function can also be implemented by a timer circuit, which is communicatively connected to the processor. In this case, the timer circuit implements the function of the aforementioned timer program, eliminating the need for a separate timer program. Compared to some existing detection circuits, the timer circuit occupies a smaller chip area, thus also reducing the chip area required for power-off detection.

[0076] In this embodiment, the USB protocol specifies that the first signal packet is sent periodically. If the first signal packet is lost, it may be due to a power outage. Therefore, the first signal packet can be detected within a first preset time period to determine whether the first signal packet is lost, thereby determining whether a power outage has occurred. Since the first signal packet is sent and detected periodically by the USB protocol, it does not affect the transmission of audio data and does not require additional circuitry. Thus, the chip area required for power outage detection of the USB interface can be effectively reduced.

[0077] Based on the same inventive concept, embodiments of this application also provide an audio playback system. Please refer to... Figure 7 The audio playback system includes: an audio playback device 100 and an audio source device 200.

[0078] The audio playback device is any of the audio playback devices described in the foregoing embodiments, and will not be elaborated further here. The audio source device 200 supports USB and can transmit audio data to the audio playback device via USB. For example, the audio source device 200 can be a mobile phone, computer, etc.

[0079] Based on the same inventive concept, embodiments of this application also provide a storage medium storing instructions thereon, which, when run, execute the methods provided in the above embodiments.

[0080] The storage medium can be any available medium accessible by a module with processing capabilities, or a data storage device such as a server or data center that integrates one or more available media. The available medium can be magnetic media (e.g., floppy disks, hard disks, magnetic tapes), optical media (e.g., DVDs), or semiconductor media (e.g., SSDs (Solid State Disks)). The module with processing capabilities can be the USB module described in the preceding embodiments.

[0081] In the embodiments provided in this application, it should be understood that the disclosed methods can also be implemented in other ways. The device embodiments described above are merely illustrative. The functional modules in the various embodiments of this application can be integrated together to form an independent part, or each module can exist independently, or two or more modules can be integrated to form an independent part.

[0082] If the aforementioned functions are implemented as software functional modules and sold or used as independent products, they can be stored in a storage medium. Based on this understanding, the technical solution of this application, in essence, or the part that contributes to the prior art, or a portion of the technical solution, can be embodied in the form of a software product. This product is stored in a storage medium and includes several instructions to cause one or more modules with processing capabilities (which may be personal computers, servers, or network devices, etc.) to execute all or part of the steps of the methods described in the various embodiments of this application. The aforementioned storage medium includes various media capable of storing program code, such as USB flash drives, external hard drives, ROM, RAM, magnetic disks, or optical disks.

[0083] The above description is merely a specific embodiment of this application, but the scope of protection of this application is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the scope of the technology disclosed in this application should be included within the scope of protection of this application. Therefore, the scope of protection of this application should be determined by the scope of the claims.

[0084] It should be noted that, in this document, the terms "comprising," "including," 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. Unless otherwise specified, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes said element.

Claims

1. A power failure detection method, characterized in that, The power failure detection method, applied to audio playback devices, includes: During the playback of audio data, a first signal packet is detected; the audio source device is connected to the audio playback device via a USB interface, and the audio source device supplies power to the audio playback device via the USB interface; the first signal packet is a signal packet periodically emitted by the audio source device based on the USB protocol; If no next first signal packet is detected within a first preset duration, it is determined that the audio playback device is powered off; the first preset duration is longer than the period of sending the first signal packet, and the first preset duration is shorter than the preset power-off duration of the audio playback device; After determining that the audio playback device is powered off, the method further includes: disabling the audio data output; and controlling the power off of each circuit in the audio playback device that outputs the audio data. After the power is turned off to each circuit inside the audio playback device, the method further includes: continuing to detect the first signal packet; if the first signal packet is detected within a second preset duration, then restoring the power supply to each circuit inside the audio playback device and restoring the output of the audio data; wherein, the second preset duration is located between the first preset duration and the period duration of sending the first signal packet; the sum of the second preset duration and the first preset duration is less than the preset power-off duration of the audio playback device.

2. The power failure detection method according to claim 1, characterized in that, The audio playback device includes a timer program configured to restart timing in response to the detection of the first signal packet; The timer program is also configured with the first preset duration; After detecting the first signal packet, the power failure detection method further includes: If it is determined that the timer program's timing exceeds the first preset duration, then it is determined that no next first signal packet was detected within the first preset duration.

3. The power failure detection method according to claim 1, characterized in that, Before detecting the first signal packet, the method further includes: The first preset duration is determined based on the speed mode of the USB protocol used by the audio playback device; The period for transmitting the first signal packet varies depending on the speed mode.

4. The power failure detection method according to claim 1, characterized in that, The first signal packet is the frame header packet.

5. An audio playback device, characterized in that, include: The USB interface is used to connect to an audio source device to receive audio data sent by the audio source device, a first signal packet periodically sent based on the USB protocol, and power provided by the audio source device. A USB module is connected to the USB interface, and the USB module is used to obtain the first signal packet from the USB interface; The USB module is also configured to perform the power failure detection method as described in any one of claims 1-4.

6. The audio playback device according to claim 5, characterized in that, The audio playback device further includes: a processor connected to the USB module, the processor being configured with a timer program; the timer program being configured to restart timing in response to the detection of the first signal packet; the timer program being configured with the first preset duration.

7. The audio playback device according to claim 5 or 6, characterized in that, The audio playback device is headphones.

8. An audio system, characterized in that, include: Audio source equipment; The audio playback device as described in any one of claims 5 to 7 is connected to the audio source device via the USB interface.

9. A storage medium, characterized in that, The storage medium stores instructions that can be executed by the USB module to implement the power failure detection method as described in any one of claims 1-4.

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