TW202231038A - Transmission control architecture between sensing device and host device - Google Patents

Abstract

A sensing device includes a sensed information transmission circuit, a control information slave circuit and a mode switching circuit. The sensed information transmission circuit is configured to convert sensed information into a transmission signal conforming to a signal format of a first transmission protocol according to the first transmission protocol. The control information slave circuit is configured to convert signals received from a signal transmission interface into control information according to a second transmission protocol, so as to configure the sensing device. The mode switching circuit is configured to activate one of the sensed information transmission circuit and the control information slave circuit based on a signal on a clock channel of the signal transmission interface, a signal on a data channel of the signal transmission interface or a signal on a power rail of the sensing device, thereby to transmit or receive signals through the signal transmission interface.

Description

A transmission control architecture between a sensing device and a master device

The present invention relates to signal transmission, in particular, to a transmission control structure using a single signal transmission interface to transmit signals of multiple transmission protocols between a main control device and a sensing device.

Today's digital microphones, such as digital MEMS (Micro-electromechanical Systems, MEMS) microphones, usually rely on a Pulse-Density Modulation (PDM) interface to transmit audio signals. The PDM interface usually has a 1-bit data channel and a clock channel for signal transmission in serial form. However, the PDM interface itself does not have a control channel and cannot transmit the control parameters related to the digital microphone, so that the digital microphone cannot change its acoustic and electrical characteristics after it leaves the factory, such as: sampling rate, sensitivity, Acoustic Overload Point (Acoustic Overload Point) Point, AOP), or filter settings, etc. Therefore, if you need to adjust the settings of the digital microphone, you need to use a transmission protocol with in-band control, such as MIPI SoundWire or /HD-Audio interface, or increase the signal connection feet to achieve. However, both approaches increase system cost and circuit complexity.

In view of this, one objective of the present invention is to provide a data/control interface integration method, which uses an existing signal transmission interface for sensing information to transmit sensing information and control information in a time-division multiplexing manner, thereby The sensing device is controlled and the sensing information is read, so as to realize the setting/characteristic adjustment of the sensing device. Since the structure of the present invention effectively integrates different signal transmission interfaces, the cost will not be greatly increased.

An embodiment of the present invention provides a sensing device. The sensing device includes: a sensing information transmission circuit, a control information slave circuit and a mode switching circuit. The sensing information transmission circuit is used for converting a sensing information into a transmission signal conforming to a signal format of the first transmission protocol according to a first transmission protocol. The control information slave circuit is used for converting a received signal received from a signal transmission interface into a control information according to a second transmission protocol, so as to set the sensing device. The mode switching circuit is coupled to the sensing information transmission circuit and the control information slave circuit, and is used for transmitting a signal on a clock channel, a signal on a data channel or one of the sensing devices according to the signal transmission interface A signal on the power rail activates one of the sensing information transmission circuit and the control information slave circuit to transmit or receive signals through the signal transmission interface.

An embodiment of the present invention provides a main control device. The main control device includes: a sensing information receiving circuit, a control information main circuit and a mode switching circuit. The sensing information receiving circuit is used for converting a received signal received from a signal transmission interface into sensing information according to a first transmission protocol. The control information main circuit is used for converting a control information into a transmission signal conforming to the signal format of the second transmission protocol according to a second transmission protocol. The mode switching circuit is coupled to the sensing information receiving circuit and the control information main circuit, and is used for adjusting a signal on a clock channel and a signal on a data channel on the signal transmission interface according to an operation mode of the main control device Or it is a signal on a power rail of the sensing device, and controls one of the sensing information receiving circuit or the control information main circuit to use the signal transmission interface to receive or transmit signals.

In the following text, numerous specific details are described in order to provide the reader with a thorough understanding of the embodiments of the present invention. However, one skilled in the art will understand how to practice the invention in the absence of one or more of the specific details, or with other methods or elements or materials, and the like. In other instances, well-known structures, materials, or operations are not shown or described in detail to avoid obscuring the core concepts of the invention.

Reference in the specification to "an embodiment" means that a particular feature, structure, or characteristic described in the embodiment may be included in at least one embodiment of the present invention. Thus, the appearances of "in an embodiment" in various places in this specification do not necessarily mean the same embodiment. Furthermore, the particular features, structures or characteristics described above may be combined in any suitable form in one or more embodiments.

Please refer to FIG. 1 , which illustrates a main control device and a sensing device applying the signal transmission interface of the present invention in an embodiment of the present invention. The main control device 100 can communicate with one or more sensing devices 200 through the signal transmission system of the present invention, so as to realize setting adjustment and sensing data reading of one or more sensing devices 200 . In some embodiments, the signal transmission interface 300 includes at least a first channel 310 and a second channel 320 . Wherein, the first channel 310 may be used for transmitting clock signals, and the second channel 320 may be used for transmitting data signals, but not limited thereto.

The main control device 100 includes a sensing information receiving circuit 110 , a control information main circuit 120 and a mode switching circuit 130 . The sensing information receiving circuit 110 is configured to convert the signal received from the second channel 320 into specific sensing information based on the clock signal on the first channel 310 according to a first transmission protocol, for example, Audio information, vibration information, pressure information, optical information or temperature information. In one embodiment, the first transmission protocol may be a transmission protocol based on pulse density modulation (Pulse Density Modulation, PDM). The control information main circuit 120 is used for sending control information to the sensing device 200 through at least one of the first channel 310 or the second channel 320 according to a second transmission protocol. Wherein, the second transmission protocol may be a synchronous transmission protocol or an asynchronous transmission protocol. For example, the synchronous transfer protocol can be I²C or Serial Peripheral Interface (SPI) protocol, while the non-synchronous transfer protocol can be Universal Asynchronous Receiver/Transmitter (UART) or single-wire (1- wire) protocol. When the second transmission protocol is a synchronous transmission protocol, the control information main circuit 120 transmits the clock signal through the first channel 310, and through at least the second channel 320 (according to the requirements of the transmission protocol, multiple non-clock signals may be required channel for communication) to transmit control information. When the second transmission protocol is an asynchronous transmission protocol, the control information main circuit 120 can pass one of the first channel 310 or the second channel 320 (eg 1-wire or UART single-ended transmission protocol), or both (such as the UART differential transmission protocol) to transmit control information. The mode switching circuit 130 can switch the usage rights of the sensing information receiving circuit 110 and the control information main circuit 120 for the first channel 310 and the second channel 320 according to the requirements of the main control device 100 . In different embodiments of the present invention, the mode switching circuit 130 can change the frequency of the signal on the first channel 310, the signal characteristic on the second channel 320, or the voltage level on a power rail 400, so as to notify the sensing in advance In the device 200, the main control device 100 is currently in a setting adjustment mode, and the control information main circuit 120 uses the signal transmission interface 300 to transmit control information, or the current main control device 100 is in a sensing information reading mode, and the sensing information The receiving circuit 110 uses the signal transmission interface 300 to receive sensing information. In one embodiment, when the control information main circuit 120 wants to transmit the control information to the sensing device 200 through the signal transmission interface 300, the mode switching circuit 130 can transmit a signal whose frequency is lower than a threshold value on the first channel 310, Alternatively, the voltage level on the power rail 400 may be increased. In this way, the sensing device 200 can determine that the transmission signal on the signal transmission interface 300 is the control information, so as to call the corresponding circuit module to process the signal on the channel. Conversely, when the control information main circuit 120 wants to receive the sensing information through the signal transmission interface 300 , the mode switching circuit 130 can transmit a signal with a frequency higher than the threshold value on the first channel 310 , or reduce the signal on the power rail 400 . voltage level, so that the sensing device 200 can call the corresponding circuit module to transmit the sensing information. Please note that the above-mentioned method is only an implementation aspect of the present invention, and this implementation aspect is suitable when the basic clock of the first transmission protocol (eg: PDM) is higher than that of the second transmission protocol (eg: I ² C ) of the base clock. In other embodiments, if the base clock of the first transmission protocol is lower than the base clock of the second transmission protocol, the sensing device 200 may be notified of the switching of the operation mode in the opposite manner. For example, before transmitting the control information, the mode switching circuit 130 may transmit a signal with a frequency higher than a threshold value on the first channel 310, or reduce the voltage level on the power rail 400, so that the sensing device 200 is sufficient to determine the signal transmission The transmission signal on the interface 300 is control information. On the contrary, before receiving the sensing information, the mode switching circuit 130 can transmit a signal with a frequency lower than the threshold value on the first channel 310, or increase the voltage level on the power rail 400, so that the sensing device 200 can call The corresponding circuit module transmits the sensing information. In other words, in the embodiment of the present invention, according to the high-low relationship between the signal frequency on the first channel 310 and the frequency threshold, or the high-low relationship between the voltage level on the power rail 400 and the voltage threshold, to reflect whether the main control device 100 is in the setting adjustment mode or the sensing information reading mode.

In addition to the above methods, in other embodiments of the present invention, the main control device 100 can also notify the sensing device 200 of the mode switch through the signal feature on the second channel 320 . For example, the mode switching circuit 130 may transmit a signal with a specific pattern on the second channel 320 to the sensing device 200 within a specific time interval to inform the sensing device 200 that the current master control device 100 is located mode of operation so that it can respond appropriately. For example, a codec rule and a signal pattern can be preset/agreed between the main control device 100 and the sensing device 200 . When the sensing device 200 decodes the packet from the master device 100, and the decoded packet content corresponds to a pre-agreed simple signal content or a series of cadence signal content (for example, but not limited to, the signal content Displays continuously appearing up, down, down, left, right, left, right, BA (before being converted into two bits)..., or a specific signal type such as 11011100), the sensing device 200 can determine that the transmission signal on the signal transmission interface 300 is control information , so as to call the corresponding circuit module to process the signal on the second channel 320 .

The sensing device 200 includes a sensing information transmission circuit 210 , a control information slave circuit 220 and a mode switching circuit 230 . The sensing information transmission circuit 210 is used for converting the sensing signal generated by the sensing module 240 into data on the second channel 320 based on the clock signal on the first channel 310 according to the first transmission protocol The signal is transmitted to the main control device 100 . In one embodiment, the sensing module 240 (when the sensing device 200 is a digital microphone) may include an audio-electric conversion device, an analog-to-digital converter, a signal processing circuit, and the like. In another embodiment, the sensing module 240 (eg, when the sensing device 200 is a temperature sensing device) may include a thermoelectric conversion device, an analog-to-digital converter, a signal processing circuit, etc., but not limit. In addition, in more embodiments of the present invention, the sensing module 240 may also be a vibration sensor, a pressure sensor or an optical sensor. Furthermore, the control information slave circuit 220 is used for converting the signal received from at least one of the first channel 310 or the second channel 320 into control information according to the second transmission protocol, so as to control the sensing module 240 Or other circuit elements in the sensing device 200 to perform setting adjustment. The setting parameters used by one or more elements in the sensing module 240 or the sensing device 200 can be adjusted through control information. In one embodiment, these setting parameters may include (but are not limited to): sampling rate, sensitivity, gain control, Acoustic Overload Point (AOP), or filter setting and the like. Furthermore, the mode switching circuit 230 includes a mode detection circuit 232 and a mode control circuit 234 . The mode detection circuit 232 can determine whether the current operating mode of the main control device 110 is the setting adjustment mode or the sensing information reading mode according to the signal frequency on the first channel 310 or the voltage level on the power rail 400 . The mode control circuit 234 controls the sensing information transmission circuit 210 and the control information slave circuit 220 to transmit or receive signals through the signal transmission interface 300 according to the judgment result of the mode detection circuit 232 .

In the embodiment of the present invention, the hysteresis control technique is also added to the mode switching, so as to ensure that the control information transmitted by the main control device 100 will not be missed by the sensing device 200 . For details of this feature, please refer to the architecture diagram shown in FIG. 2 and the timing diagram shown in FIG. 3 further. First, as shown in FIG. 2 , the mode detection circuit 232 of the sensing device 200 further includes a static detection unit 2321 and a frequency detection unit 2322 . Furthermore, as shown in FIG. 3 , before the main control device 100 enters the setting adjustment mode or the sensing information reading mode, the mode switching circuit 130 will be required to transmit a DC signal through the first channel 310 , and the DC signal may have logic. High level or logic low level, when the static detection unit 2321 detects that the signal on the first channel 310 maintains the DC state for a period of time (state A), it will determine that the main control device 100 enters the setting adjustment mode (state B), the mode control circuit 234 is further required to perform mode switching, so that the sensing device 200 enters the setting adjustment mode, and activates the control information slave circuit 220 (state C). After that, the control information main circuit 120 transmits the control information in the signal format of the second transmission protocol through the first channel 310 and the second channel 320 (state D). After the control information main circuit 120 completes the transmission of the control information, the mode switching circuit 130 transmits the DC signal on the first channel 310 again (state E). At this time, the frequency detection unit 2322 does not detect that the frequency reaches the predetermined threshold, which produces a hysteresis effect, and determines that the main control device 100 is still in the setting adjustment mode (state F), so the mode control circuit 234 continues to maintain the setting adjustment mode. mode, the control information slave circuit 220 is continuously activated (state G). After that, when the main control device 100 intends to start reading the sensing information, the mode control circuit 130 will make the sensing information receiving circuit 110 send out a clock signal conforming to the first transmission protocol on the first channel 310 (state H ). At this time, the frequency detection unit 2322 will detect that the frequency of the signal on the first channel 310 is greater than a frequency threshold TH (for example, 400K Hz), so as to determine that the main control device 100 switches the mode to the sensing information reading mode (state I), and further requires the mode control circuit 234 to activate the sensing information transmission circuit 210 (state J). Afterwards, the sensing information transmission circuit 210 transmits the sensing information generated by the sensing module 240 to the main control device 100 through the second channel 320 in a format compatible with the second transmission protocol (state K). However, in the sensing information reading mode, if the frequency detection unit 2322 detects that the signal frequency on the first channel 310 is lower than the frequency threshold TH (state L, state M), the static detection unit 2321 The DC state on the first channel 310 is not detected, so the mode switching circuit 230 will not immediately allow the mode control circuit 234 to activate the control information slave circuit 220 to enter the setting adjustment mode, and will not end the sensing information reading mode. . Instead, it has to wait until the static detection unit 2321 detects that the signal on the first channel 310 maintains the DC state, and then determines that the master control device 100 enters the setting adjustment mode, allowing the mode control circuit 234 to activate the control information slave circuit 220 . The details of the above mode switching can also be further known from the schematic diagram shown in FIG. 4 , wherein, in the setting adjustment mode, the frequency needs to be increased above the threshold TH before switching to the sensing information reading mode. However, once the frequency is lower than the threshold TH, it does not switch to the sensing information reading mode immediately, but does not switch to the sensing information reading mode until the frequency is zero (DC state).

FIG. 5 further illustrates a detailed structure of a master device simultaneously controlling and accessing a plurality of sensing devices in an embodiment of the present invention. As shown in the figure, the main control device 100 controls and accesses the sensing devices 200_1 to 200_3 through the first channel 310 , the second channel 320 and the third channel 330 . Please note that, in this embodiment, the number of sensing devices that can be simultaneously accessed by the main control device 100 is not limited by the present invention. The main control device 100 mainly includes a main control circuit 150 , one or more sensing information receiving circuits 110_1 - 110_3 , control information main circuits 120_1 - 120_3 , multiplexers 161 - 169 and logic control circuits 171 - 173 . In this embodiment, the control information main circuits 120_1 ˜ 120_3 are substantially I ² C main circuits, which control the sensing devices 200_1 ˜ 200_3 according to the I ² C transmission protocol. Therefore, the multiplexers 161~162, 164~165, 167~168, the logic control circuits 171~173 and the resistors 181~186 are required to meet the requirements of the I ² C transmission protocol, so that the signals on the channels can be pulled up or down ( Since the I ² C main circuit adopts an open-drain architecture). Accordingly, in other embodiments of the present invention, if the control information main circuits 120_1 to 120_3 are not the I ² C main circuits, the above circuit elements can be ignored.

The main control circuit 150 can determine the operation mode of the main control device 100 to be the setting adjustment mode or the sensing information reading mode. The main control circuit 105 controls the multiplexer 163 to determine which of the sensing information receiving circuit 110_1 or the control information main circuit 120_1 generates a clock signal that can be transmitted to the clock channel 310 through the clock pad 191 . In the setting adjustment mode, the multiplexer 163 enables the clock signal generated by the control information main circuit 120_1 to be transmitted to the clock channel 310 and received by the sensing devices 200_1 to 200_3. At the same time, the signals generated by the control information main circuit 120_2 and/or 120_3 can be transmitted to the data channels 320 and 330 through the data pads 192 and 193 . Among them, these data signals include specific control information, such as device ID and control parameters. Once the mode detection circuits 232_1 to 232_3 of the sensing devices 200_1 to 200_3 detect that the signal of the clock channel 310 is in the DC state, the mode is switched to the setting adjustment mode, and the control information slave circuit (ie, I ² C is activated) The slave circuits 220_1 to 220_3 receive the signals on the data channels 320 and 330 . In addition, the sensing devices 200_1 to 200_3 selectively adjust the setting parameters according to the device ID in the signal. In addition, the main control circuit 150 enables the control information main circuit 120_2 and/or 120_3 to receive the signals on the data channels 320 and 330 from the data pads 192 and 193 through the switching of the multiplexers 166 and 169, for example, by a sensing device. The parameter setting results returned by 200_1~200_3.

On the other hand, in the sensing information reading mode, the multiplexer 163 allows the clock signal generated by the sensing information receiving circuit 110_1 to be transmitted to the clock channel 310 through the clock pad 191, and sent to the clock channel 310 by the sensing device 200_1. Received by ~200_3. The mode detection circuits 232_1 to 232_3 in the sensing devices 200_1 to 200_3 detect that the signal frequency of the clock channel 310 is greater than the threshold value TH, so as to switch the mode to the sensing information reading mode, and activate the sensing information transmission circuit 210_1 ~210_3. The sensing information transmission circuits 210_1 ˜ 210_3 transmit the sensing information generated by the sensing devices 200_1 ˜ 200_3 to the main control device 100 through the data channels 320 and 330 . At this time, through the switching of the multiplexers 166 and 169, the sensing information receiving circuits 110_2 and/or 110_3 can receive signals from the data channels 320 and 330 through the data pads 192 and 193, so as to obtain signals from the sensing devices 200_1~ Sensing information returned by 200_3. Please note that although in this embodiment, the main control device 100 includes sensing information receiving circuits 110_1 ˜ 110_3 and control information main circuits 120_1 ˜ 120_3 . However, in other embodiments of the present invention, part of the sensing information receiving circuit or the control information main circuit may be integrated into one. For example, the control information main circuits 120_1 ˜ 120_3 can be integrated into one, and the sensing information receiving circuits 110_1 ˜ 110_3 can also be integrated into two.

Furthermore, although in the above embodiments, the mode detection circuit 232 and the mode control circuit 234 in the sensing device 200 perform mode detection and switching based on the signal frequency on the clock channel 310 . However, in other embodiments of the present invention, the mode detection circuit 232 and the mode control circuit 234 in the sensing device 200 can also perform mode detection and switching based on the voltage level of the power rail 400 . For example, the mode switching circuit 130 in the main control device 100 can increase the voltage level of the power rail 400 to 2.7V when the main control circuit 150 decides to transmit control information, and switch the power supply to 2.7V when it decides to receive sensing information The voltage level of rail 400 is reduced to 1.8V. Accordingly, the mode detection circuit 232 and the mode control circuit 234 in the sensing device 200 can determine when to sense the information transmission circuit 210 or activate the control information slave circuit 220 according to the voltage level of the power rail 400 .

In conclusion, the present invention provides a signal transmission architecture integrating sensing information transmission/control information transmission, which enables a single signal transmission interface to support signals of multiple transmission protocols. For example, the aforementioned PDM-based transmission protocol for transmitting sensing information, and I ² C protocol, SPI protocol, UART protocol or 1-wire protocol for transmitting control information. Therefore, the present invention can control the sensing device and read sensing information without greatly increasing the hardware cost and circuit complexity, so as to realize the setting/characteristic adjustment of the sensing device. The above descriptions are only preferred embodiments of the present invention, and all equivalent changes and modifications made according to the scope of the patent application of the present invention shall fall within the scope of the present invention.

100: Master control device 110, 110_1~110_3: Sensing information receiving circuit 120, 120_1~110_3: Control information main circuit 130: Mode switching circuit 150: main control circuit 161~169: Multiplexer 171~173: Logic control circuit 181~186: Resistance 191: clock pad 192, 193: Data pads 200, 200_1~200_3: Sensing device 210, 210_1~210_3: Sensing information transmission circuit 220, 220_1~220_3: control information slave circuit 230: Mode switching circuit 232: Mode detection circuit 2321: Still Detection Unit 2322: Frequency detection unit 234: Mode control circuit 240: Sensing module 300: Signal transmission interface 310: clock channel 320, 330: data channel 400: Power rail

FIG. 1 is a schematic structural diagram of a main control device and a sensing device in an embodiment of the present invention. FIG. 2 is a detailed structural diagram of the mode detection circuit in the embodiment of the present invention. FIG. 3 is a signal timing diagram in an embodiment of the present invention. FIG. 4 is a schematic diagram of hysteresis control in an embodiment of the present invention. FIG. 5 is a detailed structural diagram of a master device simultaneously controlling and accessing a plurality of sensing devices according to an embodiment of the present invention.

100: Master control device

110: Sensing information receiving circuit

120: Control information main circuit

130: Mode switching circuit

200: Sensing device

210: Sensing information transmission circuit

220: Control information from circuit

230: Mode switching circuit

232: Mode detection circuit

234: Mode control circuit

300: Signal transmission interface

310: first channel

320: Second channel

400: Power rail

Claims (10)

A sensing device, comprising: a sensing information transmission circuit for converting a sensing information into a transmission signal conforming to a signal format of the first transmission protocol according to a first transmission protocol; a control information slave circuit for converting a received signal received from a signal transmission interface into a control information according to a second transmission protocol, so as to set the sensing device; and A mode switching circuit, coupled to the sensing information transmission circuit and the control information slave circuit, is used for transmitting a signal on a clock channel, a signal on a data channel or a signal on the sensing device according to the signal transmission interface. A signal on a power rail activates one of the sensing information transmission circuit and the control information slave circuit to transmit or receive signals through the signal transmission interface. The sensing device of claim 1, wherein the sensing device is a digital micro-electromechanical systems (MEMS) microphone, a vibration sensor, a pressure sensor, an optical sensor or a The temperature sensor, and the sensing information is an audio information, a vibration information, a pressure information, an optical information or a temperature information. The sensing device according to claim 1, wherein the first transmission protocol is a transmission protocol based on Pulse Density Modulation (PDM). The sensing device of claim 1, wherein the second transmission protocol is an I²C protocol, a Serial Peripheral Interface (SPI) protocol, a Universal Asynchronous Receiver/Transmitter (UART) protocol, or It is a single-wire (1-wire) protocol. The sensing device of claim 1, wherein the mode switching circuit comprises: a mode detection circuit, coupled to the clock channel or the power rail, for generating a detection result according to the signal on the clock channel or the signal on the power rail; and A mode switching circuit, coupled to the sensing information transmission circuit, the control information slave circuit and the mode detection circuit, is used to activate the sensing information transmission circuit and the control information slave circuit according to the detection result. one. The sensing device of claim 5, wherein when the detection result indicates that the frequency of the signal on the clock channel is higher than a first threshold, when the signal on the data channel corresponds to a signal characteristic, or the When the voltage level of the signal on the power rail is lower than a second threshold, the mode switching circuit activates the sensing information transmission circuit; and when the detection result indicates that the frequency of the signal on the clock channel is lower than the first When a threshold value or when the voltage level of the signal on the power rail is higher than the second threshold value, the mode switching circuit activates the control information slave circuit. The sensing device of claim 6, wherein when the sensing information transmission circuit is activated, the mode switching circuit will activate the control information from the control information only when the signal on the clock channel maintains a DC state. circuit. The sensing device of claim 5, wherein the detection result indicates that the frequency of the signal on the clock channel is higher or lower than a first threshold, and the decoded content of the signal on the data channel conforms to the signal characteristic When the voltage level of the signal on the power rail is compared with a second threshold value, the mode switching circuit determines to activate the sensing information transmission circuit or the control information slave circuit according to the detection result. A main control device, comprising: a sensing information receiving circuit for converting a received signal received from a signal transmission interface into a sensing information according to a first transmission protocol; a control information main circuit for converting a control information into a transmission signal conforming to a signal format of the second transmission protocol according to a second transmission protocol; and a mode switching circuit, coupled to the sensing information receiving circuit and the control information main circuit, for adjusting a signal on a clock channel and a data channel on the signal transmission interface according to an operation mode of the main control device The signal of the sensing device or the signal on a power rail of the sensing device controls one of the sensing information receiving circuit or the control information main circuit to use the signal transmission interface to receive or transmit signals. The main control device according to claim 9, wherein the sensing device is a digital micro-electromechanical systems (MEMS) microphone, a vibration sensor, a pressure sensor, an optical sensor or a The temperature sensor, and the sensing information is an audio information, a vibration information, a pressure information, an optical information or a temperature information.

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