HDMI (High Definition Multimedia Interface) detection method and device

Abstract

The invention provides an HDMI detection method and device, in the method, after a first device and a second device are connected through an HDMI cable, the first device can read an EDID of the second device, and after the EDID of the second device is read, relevant parameters on the HDMI cable can be obtained, such as the rising edge time of an IIC signal on the HDMI cable, the capacitance of the HDMI cable and the length of the HDMI cable; therefore, how to adjust the driving parameter of the HDMI signal is determined based on the acquired related parameter information, and the display compatibility on the second device is improved.

Description

Technical Field

[0001] The present application relates to the field of terminal technology, and in particular to an HDMI detection method and device. Background Art

[0002] Generally, High Definition Multimedia Interface (HDMI) can be used for set-top boxes, laptops, TVs, graphics cards, projectors and other devices. Users can connect HDMI cables to connect two devices, so that the information on one device can be output to another device for display and playback. For example, users can display the content on a laptop on a projector in a conference room via an HDMI cable. However, due to the complexity of the external networking environment and the uneven quality of networking devices and cables, the content output to the projector may have compatibility issues. Summary of the invention

[0003] The present application provides an HDMI detection method and device for improving display compatibility.

[0004] In a first aspect, the present application provides an HDMI detection method, which can be applied to a source device connected via an HDMI cable, such as a first device. Specifically, the method includes: first, the first device detects that an HDMI cable is inserted into the HDMI, and then, after reading the extended display identification data EDID of the second device connected to the other end of the HDMI cable, obtains parameters related to the HDMI cable. Finally, when the parameters related to the HDMI cable meet the set conditions, the first device adjusts the driving parameters of the HDMI signal.

[0005] Through the above technical solution, the first device serving as the display source can adjust the driving parameters of the HDMI signal based on parameters related to the HDMI cable, so that the display terminal side can normally display the content transmitted by the first device, thereby improving the display compatibility of the display terminal side.

[0006] In a possible implementation, the method further includes the following steps:

[0007] After failing to read the EDID of the second device, the first device reduces the frequency value of the IIC signal from the first frequency value to the second frequency value.

[0008] Through the above technical solution, if the first device cannot read the EDID of the second device, the IIC signal frequency can be reduced to adapt to the display capability of the second device and improve display compatibility.

[0009] In a possible implementation, the parameters related to the HDMI cable may include at least one of the following parameters: rising edge time of an integrated circuit bus IIC signal, capacitance of the HDMI cable, and length of the HDMI cable.

[0010] Through the above technical solution, the first device can decide whether to adjust the driving parameters of the HDMI signal and how to adjust the driving parameters of the HDMI signal based on at least one of the rising edge time of the IIC signal, the capacitance of the HDMI cable, and the length of the HDMI cable to improve display compatibility.

[0011] In a possible implementation, obtaining parameters related to the HDMI cable includes:

[0012] Detect the voltage of the IIC signal, and when the voltage of the IIC signal reaches the first voltage value and the second voltage value respectively, obtain a first time corresponding to the first voltage value and a second time corresponding to the second voltage value; and use the difference between the first time and the second time as the rising edge time of the IIC signal.

[0013] Through the above technical solution, the corresponding time can be obtained based on the voltage value of the detected IIC signal, and then the time difference is used as the rising edge time of the IIC signal.

[0014] In a possible implementation, when the parameter meets the set condition, the first device adjusts the driving parameter of the HDMI signal, including:

[0015] When the rising edge time of the IIC signal is greater than or equal to the first set threshold, the first device adjusts the driving parameters of the HDMI signal, which can improve the display compatibility of the display terminal side.

[0016] In a possible implementation, obtaining parameters related to the HDMI cable includes:

[0017] The first device determines a rising edge time of the IIC signal, and then determines a capacitance of the HDMI cable according to the rising edge time of the IIC signal.

[0018] Through the above technical solution, the rising edge time of the IIC signal can be detected, and the HDMI cable capacitance can be determined based on the rising edge time of the IIC signal, thereby adjusting the driving parameters of the HDMI signal based on the HDMI cable capacitance.

[0019] In a possible implementation, when the parameter meets the set condition, the first device adjusts the driving parameter of the HDMI signal, including:

[0020] When the capacitance of the HDMI cable is greater than or equal to the second set threshold, the first device adjusts the driving parameters of the HDMI signal, thereby improving the display compatibility of the display terminal side.

[0021] In a possible implementation, obtaining parameters related to the HDMI cable includes:

[0022] The first device determines the rising edge time of the IIC signal, and then determines the length of the HDMI cable according to the rising edge time of the IIC signal.

[0023] As a possible implementation, when determining the length of the HDMI cable according to the rising edge time of the IIC signal, the capacitance of the HDMI cable can be calculated according to the rising edge time of the IIC signal, and then the length of the HDMI cable can be calculated based on the capacitance of the HDMI cable.

[0024] Through the above technical solution, the rising edge time of the IIC signal can be detected, and the length of the HDMI cable can be determined based on the rising edge time of the IIC signal, thereby adjusting the driving parameters of the HDMI signal based on the HDMI cable length.

[0025] In a possible implementation, when the parameter meets the set condition, the first device adjusts the driving parameter of the HDMI signal, including:

[0026] When the length of the HDMI cable is greater than or equal to a third set threshold, the first device adjusts a driving parameter of the HDMI signal.

[0027] In a second aspect, the present application provides a device, comprising a processor; a memory and one or more programs; wherein the one or more programs are stored in the one or more memories, and the one or more programs include instructions, which, when called and executed by the one or more processors, enable the device to execute the above-mentioned first aspect and any possible design of the first aspect.

[0028] In a third aspect, the present application also provides a device comprising modules / units for executing the method of the first aspect or any possible design of the first aspect; these modules / units can be implemented by hardware, or corresponding software can be implemented by hardware.

[0029] In a fourth aspect, the present application also provides a computer-readable storage medium, in which one or more programs are stored. When the one or more programs are run on a device, the device executes the first aspect and any possible design method of the first aspect.

[0030] In a fifth aspect, the present application also provides a computer program product. When the computer program product runs on a device, the device executes the method of the first aspect of the embodiment of the present application and any possible design of the first aspect thereof.

[0031] For each aspect from the second to the fifth aspect and the technical effects that may be achieved by each aspect, please refer to the above description of the technical effects that can be achieved by various possible solutions in the first aspect, and no further details will be given here. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] Figure 1 A schematic diagram of an application scenario provided for an embodiment of the present application;

[0033] Figure 2A A schematic diagram of the structure of a terminal device 10 provided in an embodiment of the present application;

[0034] Figure 2B A schematic diagram of the structure of a terminal device 20 provided in an embodiment of the present application;

[0035] Figure 3A A schematic block diagram of an HDMI detection method provided in an embodiment of the present application;

[0036] Figure 3B A schematic diagram of the physical structure of an HDMI provided in an embodiment of the present application;

[0037] Figure 4 A flow chart of an HDMI detection method provided in an embodiment of the present application;

[0038] Figure 5 A schematic diagram of a rising edge of a clock signal provided in an embodiment of the present application;

[0039] Figure 6 Another HDMI detection method flow chart provided in the embodiment of the present application;

[0040] Figure 7 A flow chart of another HDMI detection method provided in an embodiment of the present application;

[0041] Figure 8 A flow chart of an HDMI detection method provided in an embodiment of the present application;

[0042] Fig. 9 A schematic diagram of the structure of a device provided in an embodiment of the present application. DETAILED DESCRIPTION

[0043] The technical solutions in the embodiments of the present application will be described in detail below in conjunction with the drawings in the following embodiments of the present application.

[0044] It should be understood that at least one of the following embodiments includes one or more, wherein more means greater than or equal to two. In addition, it should be understood that in the description of this application, the words "first", "second" and the like are only used for the purpose of distinguishing the description.

[0045] For example, Figure 1 FIG. 1 is a schematic diagram of an application scenario provided by an embodiment of the present application. Figure 1 As shown, the application scenario may include a terminal device 10 and a terminal device 20. The terminal device 10 may be a display source device, and the terminal device 20 may be a display terminal device. Both the terminal device 10 and the terminal device 20 have HDMI interfaces, and the terminal device 10 and the terminal device 20 may be connected to an HDMI cable via HDMI, and the terminal device 10 may output images / videos to the terminal device 20 via the HDMI cable.

[0046] In some embodiments, after the terminal device 10 is connected to the terminal device 20 via an HDMI cable, the terminal device 10 can read the extended display identification data (EDID) of the terminal device 20. If the terminal device 10 cannot read the EDID of the terminal device 20, the HDMI signal frequency can be adjusted, for example, the Inter-Integrated Circuit (IIC) signal frequency in the HDMI signal can be reduced.

[0047] In some embodiments, a detection circuit can be added to the terminal device 10, and the rising edge time of the IIC signal can be detected by the detection circuit. Then, the HDMI cable capacitance is calculated according to the rising edge time of the IIC signal, or the length of the HDMI cable is estimated, and then the driving parameters of the HDMI signal are adjusted based on the HDMI cable capacitance or the HDMI cable length to improve compatibility.

[0048] It should be understood that in the embodiment of the present application, the terminal device 10 may be a device with HDMI such as a laptop, a set-top box, a projector, etc., and the terminal device 20 may be a device such as a display, etc., which is not limited in the present application. In addition, exemplary embodiments of the device include but are not limited to Or other operating systems.

[0049] The following uses a laptop as an example to introduce Figure 1 The structure of the terminal device 10 in the application scenario is shown.

[0050] For example, Figure 2A As shown, the laptop computer 100 may include a processor 110, an external memory interface 120, an internal memory 121, a universal serial bus (USB) interface 130, an HDMI 131, a detection circuit 140, a communication module 150, an audio module 160, a speaker 160A, a microphone 160B, a button 170, a display screen 180, and the like.

[0051] The processor 110 may include one or more processing units, for example: the processor 110 may include an application processor (application processor, AP), a modem processor, a graphics processor (graphics processing unit, GPU), an image signal processor (image signal processor, ISP), a controller, a memory, a video codec, a digital signal processor (digital signal processor, DSP), a baseband processor, and / or a neural-network processing unit (neural-network processing unit, NPU), etc. Among them, different processing units can be independent devices or integrated in one or more processors. Among them, the controller can be the nerve center and command center of the laptop computer 100. The controller can generate an operation control signal according to the instruction opcode and the timing signal to complete the control of fetching and executing instructions. The processor 110 can also be provided with a memory for storing instructions and data. In some embodiments, the memory in the processor 110 is a high-speed cache memory. The memory can save instructions or data that the processor 110 has just used or circulated. If the processor 110 needs to use the instruction or data again, it can be directly called from the memory. Repeated access is avoided, the waiting time of the processor 110 is reduced, and the efficiency of the system is improved.

[0052] The internal memory 121 can be used to store executable program codes, which include instructions. The processor 110 executes various functional applications and data processing of the laptop computer 100 by running the instructions stored in the internal memory 121. The internal memory 121 may include a program storage area and a data storage area. Among them, the program storage area can store an operating system, and software codes of at least one application (such as a video application, etc.). The data storage area can store data (such as videos, etc.) generated during the use of the laptop computer 100. In addition, the internal memory 121 may include a high-speed random access memory, and may also include a non-volatile memory, such as at least one disk storage device, a flash memory device, a universal flash memory, etc.

[0053] The external memory interface 120 can be used to connect an external memory card, such as a Micro SD card, to expand the storage capacity of the notebook computer 100. The external memory card communicates with the processor 110 through the external memory interface 120 to implement a data storage function, such as storing files such as pictures and videos in the external memory card.

[0054] The USB interface 130 is an interface that complies with USB standard specifications, and may specifically be a Mini USB interface, a Micro USB interface, a USB Type C interface, etc. The USB interface 130 may be used to transmit data between the notebook computer 100 and peripheral devices.

[0055] HDMI 131 is used for connecting the notebook computer 100 to other devices via an HDMI cable, so as to transmit the content on the notebook computer 100 to other devices for display.

[0056] The detection circuit 140 is used by the notebook computer 100 to detect the rising edge time of the IIC signal on the HDMI cable, and then the capacitance of the HDMI cable or the length of the HDMI cable can be calculated based on the rising edge time.

[0057] The communication module 150 includes at least one wireless communication solution of wireless local area networks (WLAN) (such as wireless fidelity (Wi-Fi) network), Bluetooth (BT), nearfield communication technology (NFC), infrared technology (IR), etc.

[0058] The notebook computer 100 can implement audio functions, such as video playback, through the audio module 160, the speaker 160A, the microphone 160C, and the application processor.

[0059] The key 170 includes a power key, etc. The key 170 may be a mechanical key or a touch key. The notebook computer 100 may receive key inputs and generate key signal inputs related to user settings and function control of the notebook computer 100.

[0060] The display screen 180 is used to display the display interface of the application, etc. The display screen 180 includes a display panel. In the embodiment of the present application, the display screen 180 can be used to display videos, pictures, etc.

[0061] Understandably, Figure 2A The components shown do not constitute a specific limitation on the laptop computer. The laptop computer may also include more or fewer components than those shown in the figure, or combine or separate some components, or arrange the components differently.

[0062] The following takes the display as an example to introduce Figure 1 The structure of the terminal device 20 in the application scenario is shown.

[0063] For example, Figure 2BAs shown, the display 200 may include a processor 210, a display screen 220, an HDMI230, a serial peripheral interface (SPI) interface 231, a video graphics array (VGA) interface 232, a display port (DP) 233, an audio interface 234, a button 240, and a memory 250.

[0064] The processor 210 is used to control the display 200 and can be used to improve the performance and reliability of the display. The processor 210 in the display 200 is usually a single chip microcomputer.

[0065] The display screen 220 is used to display pictures or videos transmitted by the notebook computer 100. The display screen 220 includes a display panel, and the display screen 220 may be a liquid crystal display (LCD) or the like.

[0066] The HDMI 230 is used to connect to other devices, such as the laptop computer 100 , via an HDMI cable, so as to transmit the content on the laptop computer 100 to the display for display.

[0067] SPI interface 231 is a Flash memory, such as a communication interface for peripheral devices such as NOR FLASH; VGA interface 232 can be used to connect with other devices for transmitting analog signals and synchronization signals; DP233 is used to connect the video source to the display 200; audio interface 234 is an audio and video input and output interface, which can be used to output audio and video.

[0068] The key 240 may include a power key, etc. The key 240 may be a mechanical key or a touch key. The display 200 may receive key input and generate key signal input related to user settings and function control of the display 200.

[0069] The memory 250 may be used to store device information of the display 200 , such as the EDID of the display 200 .

[0070] Understandably, Figure 2B The components shown do not constitute specific limitations on the display, and the display may also include more or fewer components than those shown in the figure, or combine or separate some components, or arrange the components differently.

[0071] like Figure 3A FIG. 1 is a schematic block diagram of an HDMI detection method provided in an embodiment of the present application. Figure 3AAs shown, the terminal device 10 side may include a central processing unit CPU, a detection circuit, HDMI, a single chip microcomputer, etc. The terminal device 10 may be connected to the terminal device 20 via an HDMI cable. Among them, the detection circuit can detect the rising edge time of the IIC signal given by the CPU to the HDMI, and estimate the length of the HDMI cable according to the rising edge time of the IIC signal, thereby determining how to adjust the driving parameters of the HDMI signal to improve the display compatibility of the terminal device 20 side.

[0072] For example, Figure 3B FIG. 1 is a physical structure diagram of an HDMI provided by an embodiment of the present application. Figure 3B As shown in the figure, an HDMI includes three Transition Minimized Differential Signaling (TMDS) data channels and one TMDS clock channel. Secondly, it also includes a display data channel (DDC). Among them, the HDMI Source end can be used as an HDMI transmitter (Transmitter), and the HDMI Sink end can be used as an HDMI receiver (Receiver).

[0073] Specifically, the HDMI transmitter (Transmitter) can transmit the TMDS signal to the HDMI receiver (Receiver) through TMDS Channel (channel) 0, TMDS Channel 1, TMDS Channel 2 and TMDS Clock Channel (clock channel). DDC follows the IIC protocol when transmitting data, and the terminal device 10 can communicate with the terminal device 20 based on the IIC protocol. For example, after detecting that there is a hot plug event in HDMI, the terminal device 10 can send an IIC signal to the terminal device 20 to obtain the extended display identification data (Extended Display Identification Data, EDID) of the terminal device 20.

[0074] In the embodiments of the present application, Figure 3A The detection circuit shown can be increased in Figure 3B Specifically, the IIC protocol followed by the DDC may include a serial clock line (SCL) and a serial data line (SDA), and the detection circuit may be added to the SCL line.

[0075] The HDMI detection method of the embodiment of the present application is introduced below in conjunction with the method flow chart.

[0076] like Figure 4 As shown, it is a flow chart of an HDMI detection method provided in an embodiment of the present application, see Figure 4 As shown, the method may include the following steps:

[0077] Step 401: The terminal device 10 detects that a hot plug event occurs in the HDMI.

[0078] It should be understood that hot swapping refers to allowing the user to insert, remove and replace devices on the terminal device 10 without shutting down the system or cutting off the power.

[0079] In the embodiment of the present application, the terminal device 10 detects that the HDMI has a hot plug event, which means that an HDMI cable is detected to be inserted into the HDMI of the terminal device 10, and is connected to the HDMI of the terminal device 20 through the HDMI cable. Alternatively, it can be understood that the terminal device 10 detects that one end of the HDMI cable is inserted into the HDMI of its own device, and the other end of the HDMI cable is connected to the terminal device 20.

[0080] Step 402: Determine whether the EDID of the terminal device 20 can be read. If the EDID cannot be read, continue to step 403; if the EDID can be read normally, continue to step 404.

[0081] In some embodiments, when the terminal device 10 detects that a device is connected to the HDMI, the extended display identification data (EDID) of the terminal device 20 can be read through the DDC to determine whether the EDID of the terminal device 20 can be read normally.

[0082] Step 403: Reduce the IIC signal frequency.

[0083] When the terminal device 10 cannot read the EDID of the terminal device 20, the IIC signal frequency can be reduced to adapt to the characteristics of the terminal device 20 and ensure compatibility. For example, assuming that the terminal device 10 is a laptop and the terminal device 20 is a display, the laptop can read the EDID of the display. If the EDID of the display cannot be read, the IIC signal frequency can be reduced, for example, the IIC signal frequency can be reduced from 20KHz to 10KHz. It should be understood that the signal frequency in the above example is only a schematic, and in actual applications, it can also be other values, and this application does not specifically limit this.

[0084] As a possible implementation, after reducing the IIC signal frequency, the terminal device 10 can read the EDID of the terminal device 20 again. If the EDID of the terminal device 20 is still not read, the step is terminated. For example, continuing to take a laptop and a display as an example, assuming that after the laptop reduces the IIC signal frequency from 20KHz to 10KHz, the laptop can read the EDID of the display again. If it still cannot be read, the step is terminated.

[0085] Step 404: The terminal device 10 detects the rising edge time of the IIC signal.

[0086] In some embodiments, after the terminal device 10 reads the EDID of the terminal device 20, the detection circuit of the terminal device 10 can detect the rising edge time of the IIC signal. Specifically, a comparator can be added to the clock signal line of the IIC. When the voltage of the IIC signal rises to the set threshold voltage, the comparator starts to output a low level until the high level cycle of the clock signal is completed. For example, Figure 5 As shown, it is a schematic diagram of the rising edge of a clock signal provided in an embodiment of the present application. Figure 5 In the schematic diagram shown, V th Represents the set threshold voltage of the comparator, T DDC Indicates the clock period of HDMI-DDC, t 0 Indicates the low-level pulse width of the comparator output, that is, the rising edge time.

[0087] As a possible implementation method, two comparators can be added to the clock signal line of the IIC. When the voltage rises to a first set threshold (for example, 10% of the pull-up bus power) and a second set threshold (for example, 90% of the pull-up bus power), the two comparators read the corresponding time respectively, and then the time difference between the outputs of the two comparators is used as the rising edge time.

[0088] Step 405: Determine whether the rising edge time of the IIC signal is greater than or equal to a first set threshold. If it is greater than or equal to the first set threshold, execute step 406; otherwise, display the signal normally on the terminal device 20.

[0089] Step 406: The terminal device 10 adjusts the driving parameters of the HDMI signal to obtain new parameters.

[0090] In some embodiments, after the rising edge time of the IIC signal is detected, the rising edge time of the detected IIC signal may be compared with a first set threshold value (for example, the first set threshold value may be: 2us). When it is determined that the rising edge time of the detected IIC signal is greater than or equal to the first set threshold value, the link source end, that is, the drive parameters of the HDMI inside the system on chip (SOC) in the terminal device 10 or the drive parameters of the HDMI in the link may be adjusted. That is, in the embodiment of the present application, when the rising edge time of the IIC signal is greater than or equal to the first set threshold value, the drive parameters of the link source end, that is, the terminal device 10 side, may be adjusted, and the drive parameters in the HDMI link may also be adjusted.

[0091] It should be understood that the first set threshold value may also be other values, and this application does not make any specific limitation on this.

[0092] Step 407: The terminal device 20 applies the new parameters.

[0093] After the terminal device 10 adjusts the driving parameters of the HDMI signal, the adjusted new parameters can be applied so that the new parameters take effect and are displayed normally on the terminal device 20 .

[0094] like Figure 6 As shown, it is another flow chart of HDMI detection method provided by the embodiment of the present application, refer to Figure 6 As shown, the method may include the following steps:

[0095] Step 601: The terminal device 10 detects that a hot plug event occurs in the HDMI.

[0096] Step 602: Determine whether the EDID of the terminal device 20 can be read. If the EDID cannot be read, continue to step 603; if the EDID can be read normally, continue to step 604.

[0097] Step 603: Reduce the IIC signal frequency.

[0098] Step 604: The terminal device 10 detects the rising edge time of the IIC signal.

[0099] Step 605: The terminal device 10 determines the capacitance of the HDMI cable according to the rising edge time.

[0100] Assume V cc Pull-up power for HDMIIIC bus, R pu is the pull-up resistor on the IIC bus signal, then:

[0101]

[0102] According to the above formula, the total path capacitance C can be calculated, and then based on the total capacitance C and the capacitance C of the terminal device 10 itself source The HDMI cable capacitance Ccab can be obtained as:

[0103]

[0104] The capacitance Csource of the terminal device 10 itself can be obtained through actual testing.

[0105] In the embodiment of the present application, it is possible to determine whether the HDMI cable is a long cable by the size of Ccab. It should be understood that the longer the cable, the greater the capacitance and the greater the rise time.

[0106] Step 606: Determine whether the HDMI cable capacitance is greater than or equal to the second set threshold. If the HDMI cable capacitance is greater than or equal to the second set threshold, execute step 607, otherwise, display normally on the terminal device 20.

[0107] Step 607: Adjust the driving parameters of the HDMI signal to obtain new parameters.

[0108] In some embodiments, after the HDMI cable capacitance Ccab is calculated, the calculated HDMI cable capacitance Ccab (actual HDMI cable capacitance) and the second set threshold (cable capacitance threshold required by the specification standard, for example, can be recorded as: C REF ) for comparison. When the actual HDMI cable capacitance is greater than or equal to the second set threshold, the corresponding parameters need to be adjusted so that it can be displayed normally on the terminal device 20. Exemplarily, the second set threshold C REF It can be 700pF (picofarad). When Ccab is greater than or equal to 700pF, it means that the environment in the current scene is worse than the common user environment. At this time, the link source, that is, the HDMI drive parameters inside the system on chip (SOC) in the terminal device 10 or the HDMI drive parameters in the link can be adjusted to adapt to the new environment.

[0109] The driving parameters may include driving capability, slope, amplitude, pre-emphasis, etc. For example, the amplitude may be adjusted from 400mV to 600mV.

[0110] It should be understood that the specific numerical values ​​in the above examples are for illustration only. In actual applications, the second set threshold value, amplitude, etc. may also be other numerical values, and this application does not make any specific limitation on this.

[0111] Step 608: The terminal device 20 applies the new parameters.

[0112] It should be understood that Figure 6The specific implementation of steps 601 to 604, step 607, and step 608 in the embodiment shown can be referred to in Figure 4 The detailed description of steps 401 to 404, step 406, and step 407 in the illustrated embodiment will not be repeated here.

[0113] like Figure 7 As shown, it is a flow chart of another HDMI detection method provided in the embodiment of the present application, refer to Figure 7 As shown, the method may include the following steps:

[0114] Step 701: The terminal device 10 detects that a hot plug event occurs in the HDMI.

[0115] Step 702: Determine whether the EDID of the terminal device 20 can be read. If the EDID cannot be read, continue to step 703; if the EDID can be read normally, continue to step 704.

[0116] Step 703: Reduce the IIC signal frequency.

[0117] Step 704: The terminal device 10 detects the rising edge time of the IIC signal.

[0118] Step 705: The terminal device 10 determines the length of the HDMI cable according to the rising edge time of the IIC signal.

[0119] In some embodiments, the terminal device 10 can calculate the HDMI cable capacitance based on the detected rising edge time of the IIC signal, and then estimate the length of the HDMI cable based on the HDMI cable capacitance, thereby determining whether relevant parameters need to be adjusted based on the HDMI cable length to improve the display compatibility of the terminal device 20.

[0120] pass Figure 6 The embodiment shown can calculate the HDMI cable capacitance Ccab, which can be calculated by the following formula as a possible implementation:

[0121] Assuming that the HDMI cable is an ideal transmission cable, the capacitance per unit length of the HDMI cable is:

[0122]

[0123] Among them, Z 0 represents characteristic impedance, and εr represents dielectric constant.

[0124] Then, based on the above HDMI cable capacitance Ccab and the capacitance per unit length of the ideal transmission cable, the HDMI cable length can be estimated:

[0125]

[0126] Step 706: Determine whether the length of the HDMI cable is greater than or equal to a third set threshold. If the length of the HDMI cable is greater than or equal to the third set threshold, execute step 707, otherwise display normally on the terminal device 20.

[0127] In some embodiments, after calculating the length of the HDMI cable, the length of the HDMI cable can be compared with a third set threshold. When the length of the HDMI cable is greater than or equal to the third set threshold (for example, 5 meters), the driving parameters of the HDMI signal need to be adjusted.

[0128] Step 707: The terminal device 10 adjusts the driving parameters of the HDMI signal to obtain new parameters.

[0129] Step 708: The terminal device 20 applies the new parameters.

[0130] It should be understood that Figure 7 The specific implementation of steps 701 to 704, step 707, and step 708 in the embodiment shown can be referred to in Figure 4 The detailed description of steps 401 to 404, step 406, and step 407 in the illustrated embodiment will not be repeated here.

[0131] It should be noted that all or part of the above embodiments provided in this application can be freely and arbitrarily combined with each other, and the combined technical solutions are also within the protection scope of this application.

[0132] like Figure 8 As shown, it is a flow chart of an HDMI detection method provided in an embodiment of the present application, see Figure 8 As shown, the method may include the following steps:

[0133] Step 801: The terminal device 10 detects that an HDMI cable is inserted into the HDMI port of the terminal device.

[0134] Among them, the HDMI cable is used to connect the terminal device 10 and the terminal device 20, one end of the HDMI cable is inserted into the HDMI of the terminal device 10, and the other end is inserted into the HDMI of the terminal device 20.

[0135] Step 802: After reading the EDID of the terminal device 20, the terminal device 10 obtains parameters related to the HDMI cable.

[0136] The parameters related to the HDMI cable may include at least one of the following parameters: rising edge time of the IIC signal, capacitance of the HDMI cable, and length of the HDMI cable.

[0137] In some embodiments, when the terminal device 10 detects that an HDMI cable is inserted into the HDMI, the EDID of the terminal device 20 can be read. If the EDID of the terminal device 20 is read, the parameters related to the HDMI cable can be obtained, so that the driving parameters can be adjusted based on the parameters related to the HDMI cable, so that the terminal device 20 can display the picture normally and improve the compatibility.

[0138] In other embodiments, when the terminal device 10 cannot read the EDID of the terminal device 20, the frequency of the IIC signal may be reduced.

[0139] Step 803: When the parameters related to the HDMI cable meet the set conditions, the terminal device 10 adjusts the driving parameters of the HDMI signal.

[0140] Specifically, the following three situations may be included in the embodiments of the present application:

[0141] Case 1: When the rising edge time of the IIC signal is greater than or equal to the first set threshold, the driving parameters of the HDMI signal are adjusted.

[0142] Case 2: When the capacitance of the HDMI cable is greater than or equal to the second set threshold, the driving parameters of the HDMI signal are adjusted.

[0143] Case 3: When the length of the HDMI cable is greater than or equal to the third set threshold, the driving parameters of the HDMI signal are adjusted.

[0144] For the above three situations, how to detect the rising edge time of the IIC signal. For the specific implementation of calculating the HDMI cable capacitance and the HDMI cable length, please refer to the above Figure 4 to Figure 7 The detailed description in the illustrated embodiment will not be repeated here.

[0145] In the embodiments provided by the present application, the method provided by the embodiments of the present application is introduced from the perspective of the terminal device. In order to implement the functions in the methods provided by the embodiments of the present application, the terminal device may include a hardware structure and / or a software module, and implement the above functions in the form of a hardware structure, a software module, or a hardware structure plus a software module. Whether a function of the above functions is executed in the form of a hardware structure, a software module, or a hardware structure plus a software module depends on the specific application and design constraints of the technical solution.

[0146] like Fig. 9 As shown, some other embodiments of the present application disclose a device, which may be a terminal device with a display screen. Fig. 9As shown, the device 900 includes: a display screen 901; one or more processors 902; one or more memories 903; one or more sensors 904 (not shown in the figure), multiple applications 905 (not shown in the figure); and one or more computer programs 906 (not shown in the figure), and the above-mentioned components can be connected via one or more communication buses 907.

[0147] The display screen 901 is used to display videos, pictures, etc. The memory 903 stores one or more computer programs, and when the instructions are called and executed by the one or more processors 902, the device 900 executes the method steps in the above embodiment.

[0148] In the embodiment of the present application, the processor 902 can be a general-purpose processor, a digital signal processor, an application-specific integrated circuit, a field programmable gate array or other programmable logic device, a discrete gate or transistor logic device, a discrete hardware component, and can implement or execute the methods, steps and logic block diagrams disclosed in the embodiment of the present application. The general-purpose processor can be a microprocessor or any conventional processor, etc. The steps of the method disclosed in the embodiment of the present application can be directly embodied as a hardware processor to be executed, or the hardware and software modules in the processor can be combined and executed. The software module can be located in the memory 903, and the processor 902 reads the program instructions in the memory 903, and completes the steps of the above method in combination with its hardware.

[0149] In the embodiment of the present application, the memory 903 may be a non-volatile memory, such as a hard disk drive (HDD) or a solid-state drive (SSD), etc., or a volatile memory (volatile memory), such as RAM. The memory may also be any other medium that can be used to carry or store the desired program code in the form of instructions or data structures and can be accessed by a computer, but is not limited thereto. The memory in the embodiment of the present application may also be a circuit or any other device that can implement a storage function, for storing instructions and / or data.

[0150] Those skilled in the art can clearly understand that, for the convenience and brevity of description, the specific working processes of the above-described devices and units can refer to the corresponding processes in the aforementioned method embodiments and will not be repeated here.

[0151] Based on the above embodiments, the present application further provides a computer storage medium, in which a computer program is stored. When the computer program is executed by a computer, the computer executes the method provided in the above embodiments.

[0152] A computer program product is also provided in an embodiment of the present application, including instructions, which, when executed on a computer, enable the computer to execute the method provided in the above embodiment.

[0153] The embodiments of the present application are described with reference to the flowcharts and / or block diagrams of the methods, devices (systems), and computer program products according to the embodiments of the present application. It should be understood that each process and / or box in the flowchart and / or block diagram, as well as the combination of the processes and / or boxes in the flowchart and / or block diagram, can be implemented by instructions. These instructions can be provided to a processor of a general-purpose computer, a special-purpose computer, an embedded processor, or other programmable data processing device to generate a machine, so that the instructions executed by the processor of the computer or other programmable data processing device generate instructions for implementing the process in the flowchart. Figure 1 A process or multiple processes and / or boxes Figure 1 A device that provides the functions specified in a block or multiple blocks.

[0154] These computer program instructions may also be stored in a computer readable memory capable of directing a computer or other programmable data processing device to operate in a specific manner, so that the instructions stored in the computer readable memory produce an article of manufacture including an instruction device, which implements the process Figure 1 A process or multiple processes and / or boxes Figure 1 A function specified in one or more boxes.

[0155] These computer program instructions can also be loaded onto a computer or other programmable data processing device so that a series of operating steps are executed on the computer or other programmable device to produce a computer-implemented process, thereby providing instructions for implementing the process in the computer or other programmable device. Figure 1 A process or multiple processes and / or boxes Figure 1 The steps for the functions specified in one or more boxes.

Claims

1. An HDMI detection method, characterized in that, it includes: The first device detects that an HDMI cable is inserted into the High-Definition Multimedia Interface (HDMI) on its own device, and the HDMI cable is used to connect the first device and the second device; After the first device reads the Extended Display Identification Data (EDID) of the second device, it obtains parameters related to the HDMI cable; When the parameters meet the set conditions, the first device adjusts the driving parameters of the HDMI signal.

2. The method according to claim 1, characterized in that, The parameters related to the HDMI cable include at least one of the following parameters: The rising edge time of the Inter-Integrated Circuit (IIC) signal, the capacitance of the HDMI cable, and the length of the HDMI cable.

3. The method according to claim 1 or 2, characterized in that, The method further includes: After the first device fails to read the EDID of the second device, it reduces the IIC signal frequency value from a first frequency value to a second frequency value.

4. The method according to any one of claims 1-3, characterized in that, The obtaining of the parameters related to the HDMI cable includes: Detecting the voltage of the IIC signal, and when the voltage of the IIC signal reaches a first voltage value and a second voltage value respectively, obtaining the first time corresponding to the first voltage value and the second time corresponding to the second voltage value; Taking the difference between the first time and the second time as the rising edge time of the IIC signal.

5. The method according to claim 4, characterized in that, The step that when the parameters meet the set conditions, the first device adjusts the driving parameters of the HDMI signal includes: When the rising edge time of the IIC signal is greater than or equal to a first set threshold, the first device adjusts the driving parameters of the HDMI signal.

6. The method according to any one of claims 1-3, characterized in that, The obtaining of the parameters related to the HDMI cable includes: The first device determines the rising edge time of the IIC signal; The first device determines the capacitance of the HDMI cable according to the rising edge time of the IIC signal.

7. The method according to claim 6, characterized in that, The step that when the parameters meet the set conditions, the first device adjusts the driving parameters of the HDMI signal includes: When the capacitance of the HDMI cable is greater than or equal to a second set threshold, the first device adjusts the driving parameters of the HDMI signal.

8. The method according to any one of claims 1-3, characterized in that, The obtaining of the parameters related to the HDMI cable includes: The first device determines the rising edge time of the IIC signal; The first device determines the length of the HDMI cable according to the rising edge time of the IIC signal.

9. The method according to claim 8, characterized in that, The step that when the parameters meet the set conditions, the first device adjusts the driving parameters of the HDMI signal includes: When the length of the HDMI cable is greater than or equal to a third set threshold, the first device adjusts the driving parameters of the HDMI signal.

10. A device, characterized in that, the device includes a transceiver; a processor; a memory; and one or more computer programs; wherein, the one or more computer programs are stored in the one or more memories, and the one or more computer programs include instructions that, when executed by the one or more processors, cause the device to perform the method according to any one of claims 1 to 9.

11. A computer-readable storage medium, in which instructions are stored, characterized in that, when the instructions are run on a device, the device is caused to perform the method according to any one of claims 1 to 9.

12. A computer program product, characterized in that, when the computer program product is run on a device, the device is caused to perform the method according to any one of claims 1 to 9.

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