Method for processing reading of cable id for hdmi active cable and related products

Abstract

The application discloses a method for processing reading of a cable ID of an HDMI active cable and related products, and the method comprises the steps of listening to an HDMI-SCL signal line and an HDMI-SDA signal line of the HDMI active cable by using a serial communication device. The serial communication device outputs all or part of the cable ID through the HDMI-SCL signal line and the HDMI-SDA signal line in response to sequentially detecting a plurality of first signal sequences and a second signal sequence; wherein the data of the cable ID starting from an offset value and having a length is determined according to the offset value and the length obtained from the plurality of first signal sequences; and the serial communication device further identifies that the processing of the reading of the cable ID is completed in response to sequentially detecting a third signal sequence. The scheme replaces the I2C on-chip peripheral with other serial communication devices in a general MCU, and can listen to and respond to data on the I2C channel while meeting the non-response I2C slave address, so that the reading of the cable ID data of the HDMI2.1 protocol is completed.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of active cable data processing. More particularly, the present application relates to a method for processing reading of Cable ID for HDMI active cable, a method for reading Cable ID of HDMI active cable and a device for processing reading of Cable ID for HDMI active cable. BACKGROUND

[0002] HDMI2.1 (HDMI, High Definition Multimedia Interface) protocol increases the single channel maximum bandwidth to 12Gbps. In order to overcome the problem of signal attenuation of long distance copper wire, a high speed signal processing chip can be added in the cable to reformat the signal. However, the HDMI source device can only provide a maximum of 55mA current, which is obviously not enough for the cable with added active chip. In order to solve the above problem, the HDMI2.1 protocol adds the PCA (Power for Cable Assemblies) function, and the source device can provide up to 300mA current for the cable and the slave device.

[0003] The PCA function depends on the CableID stored in the cable. The CableID is a set of data structures indicating the function, performance and manufacturer information of the HDMI cable, which is read by the source device. For one-way transmission or Category 3 cable requiring PCA power supply, the CableID is a necessary item for HDMI certification test.

[0004] According to the HDMI2.1 protocol, the source device completes the reading of the cable CableID on the I2C bus by using the IDCC (ID Communications Channel) protocol, which requires the CableID processing module in the cable to listen to the data sent by the source device on the I2C channel and respond to the CableID data structure, while requiring that the CableID processing module cannot respond to the I2C slave address (NACK, Not Acknowledge, Not Acknowledge / Not Respond / Not Ready).

[0005] However, the current MCU (Microcontroller Units) on-chip I2C peripheral Slave mode is usually used to complete the monitoring and response of I2C data, but if the requirement of not responding to the I2C slave address is met, the internal state machine of the I2C peripheral cannot realize the complete I2C data processing function, that is, it cannot monitor and respond to the data on the I2C channel. That is, the standard I2C peripheral cannot respond to the I2C address as a slave, so the CableID data reading operation cannot be realized.

[0006] Therefore, it is urgent to provide a method for processing reading of Cable ID for HDMI active cable, a method for reading Cable ID of HDMI active cable, and a device for processing reading of Cable ID for HDMI active cable, which can replace the I2C on-chip peripheral with other serial communication devices in the general MCU on-chip, so that the data on the I2C channel can be monitored and responded to while meeting the requirement of not responding to the I2C slave address, thereby realizing the CableID data reading function of HDMI2.1 protocol. SUMMARY

[0007] In order to at least solve one or more technical problems as mentioned above, the present application proposes, in multiple aspects, a method for processing reading of Cable ID for HDMI active cable, a method for reading Cable ID of HDMI active cable, and a device for processing reading of Cable ID for HDMI active cable.

[0008] In a first aspect, the present application provides a method for processing reading of a Cable ID for an HDMI active cable, the method comprising: listening, by a serial communication device, to an HDMI-SCL signal line and an HDMI-SDA signal line of the HDMI active cable, wherein the serial communication device comprises a first pin connected to the HDMI-SCL signal line and a second pin connected to the HDMI-SDA signal line; in response to sequentially detecting a plurality of first signal sequences and a second signal sequence on the HDMI-SCL signal line and the HDMI-SDA signal line, outputting, by the serial communication device, all or part of the Cable ID via the HDMI-SCL signal line and the HDMI-SDA signal line; wherein the data of the Cable ID having a length and starting from an offset value is determined according to the offset value and the length obtained from the plurality of first signal sequences; in response to sequentially detecting a third signal sequence on the HDMI-SCL signal line and the HDMI-SDA signal line, identifying, by the serial communication device, that the processing of reading of the Cable ID is completed.

[0009] In one embodiment, the first signal sequence comprises an I2C start signal, an I2C address 0xA0, an I2C ACK signal, I2C data, an I2C ACK signal, an I2C restart signal, an I2C address 0xA1, an I2C ACK signal, I2C data EDID, an I2C NACK signal, and an I2C stop signal appearing sequentially.

[0010] In one embodiment, the plurality of first signal sequences comprises five first signal sequences.

[0011] In one embodiment, the I2C data of the first first signal sequence of the plurality of first signal sequences is 0xAE, the I2C data of the second first signal sequence of the plurality of first signal sequences is 0x6E, the I2C data of the third first signal sequence of the plurality of first signal sequences is 0x61, the I2C data of the fourth first signal sequence of the plurality of first signal sequences is the offset value Offset, and the I2C data of the fifth first signal sequence of the plurality of first signal sequences is the length Length, wherein Length is a numerical value of the length.

[0012] In one embodiment, the second signal sequence comprises an I2C start signal, an I2C address 0xA0, an I2C ACK signal, I2C data 0x01, an I2C ACK signal, an I2C restart signal, an I2C address 0xA1, and an I2C ACK signal appearing sequentially.

[0013] In one embodiment, the outputting the data of the Cable ID with the length and from the offset value via the HDMI-SCL signal line and the HDMI-SDA signal line comprises: outputting a plurality of fourth signal sequences via the HDMI-SCL signal line and the HDMI-SDA signal line.

[0014] In one embodiment, the fourth signal sequence comprises one byte data of the Cable ID.

[0015] In one embodiment, the number of the fourth signal sequences is equal to the length.

[0016] In one embodiment, the I2C data of the first fourth signal sequence is the first byte of the Cable ID, the I2C data of the second fourth signal sequence is the second byte of the Cable ID, and the I2C data of the Lengthth fourth signal sequence is the Lengthth byte of the Cable ID, where Length is the numerical value of the length.

[0017] In one embodiment, after outputting one fourth signal sequence via the HDMI-SCL signal line and the HDMI-SDA signal line, the device further outputs the next fourth signal sequence via the HDMI-SCL signal line and the HDMI-SDA signal line in response to detecting an I2C ACK signal from the HDMI-SCL signal line and the HDMI-SDA signal line.

[0018] In one embodiment, detecting the first signal sequence on the HDMI-SCL signal line and the HDMI-SDA signal line comprises: identifying occurrence of the I2C start signal according to that a falling edge is detected on the HDMI-SDA signal line when a high level occurs on the HDMI-SCL signal line; identifying occurrence of the I2C address 0xA0 according to that data 0xA0 is received on the HDMI-SDA signal line under clock driving on the HDMI-SCL signal line; identifying occurrence of the I2C ACK signal according to that a low level is detected on the HDMI-SDA signal line under next clock driving on the HDMI-SCL signal line; identifying occurrence of the I2C data according to that I2C data is received on the HDMI-SDA signal line under clock driving on the HDMI-SCL signal line; identifying occurrence of the I2C ACK signal according to that a low level is detected on the HDMI-SDA signal line under next clock driving on the HDMI-SCL signal line; identifying occurrence of the I2C restart signal according to that a falling edge is detected on the HDMI-SDA signal line when a high level occurs on the HDMI-SCL signal line; identifying occurrence of the I2C address 0xA1 according to that data 0xA1 is received on the HDMI-SDA signal line under clock driving on the HDMI-SCL signal line; identifying occurrence of the I2C ACK signal according to that a low level is detected on the HDMI-SDA signal line under next clock driving on the HDMI-SCL signal line; identifying occurrence of the I2C data EDID according to that one byte data of the I2C data EDID is received on the HDMI-SDA signal line under clock driving on the HDMI-SCL signal line; identifying occurrence of the I2C NACK signal according to that a high level is detected on the HDMI-SDA signal line under next clock driving on the HDMI-SCL signal line; and identifying occurrence of the I2C stop signal according to that a rising edge is detected on the HDMI-SDA signal line when a high level occurs on the HDMI-SCL signal line.

[0019] In one embodiment, detecting a second signal sequence on the HDMI-SCL signal line and the HDMI-SDA signal line comprises: identifying occurrence of the I2C start signal according to that a falling edge is detected on the HDMI-SDA signal line when a high level occurs on the HDMI-SCL signal line; identifying occurrence of the I2C address 0xA0 according to that a data 0xA0 is received on the HDMI-SDA signal line under clock driving on the HDMI-SCL signal line; identifying occurrence of the I2C ACK signal according to that a low level is detected on the HDMI-SDA signal line under next clock driving on the HDMI-SCL signal line; identifying occurrence of the I2C data 0x01 according to that a I2C data 0x01 is received on the HDMI-SDA signal line under clock driving on the HDMI-SCL signal line; identifying occurrence of the I2C ACK signal according to that a low level is detected on the HDMI-SDA signal line under next clock driving on the HDMI-SCL signal line; identifying occurrence of the I2C restart signal according to that a falling edge is detected on the HDMI-SDA signal line when a high level occurs on the HDMI-SCL signal line; identifying occurrence of the I2C address 0xA1 according to that a data 0xA1 is received on the HDMI-SDA signal line under clock driving on the HDMI-SCL signal line; identifying occurrence of the I2C ACK signal according to that a low level is detected on the HDMI-SDA signal line under next clock driving on the HDMI-SCL signal line.

[0020] In one embodiment, detecting a third signal sequence on the HDMI-SCL signal line and the HDMI-SDA signal line comprises: identifying occurrence of the I2C NACK signal according to that a high level is detected on the HDMI-SDA signal line under next clock driving on the HDMI-SCL signal line; identifying occurrence of the I2C stop signal according to that a rising edge is detected on the HDMI-SDA signal line when a high level occurs on the HDMI-SCL signal line.

[0021] In one embodiment, outputting a fourth signal sequence through the HDMI-SCL signal line and the HDMI-SDA signal line comprises: outputting one byte data of the Cable ID through the HDMI-SDA signal line under clock driving on the HDMI-SCL signal line, wherein the one byte data is located at an offset from a start position of the Cable ID, and the offset is the offset value plus m minus 1, wherein the current output fourth signal sequence is the mth fourth signal sequence in the plurality of fourth signal sequences, and m is a positive integer greater than or equal to 1.

[0022] In one embodiment, detecting an I2C ACK signal from the HDMI-SCL signal line and the HDMI-SDA signal line comprises: identifying that the I2C ACK signal occurs when a low level is detected on the HDMI-SDA signal line according to a next clock drive on the HDMI-SCL signal line.

[0023] In one embodiment, the serial communication device is an SPI communication device, the first pin is a clock pin of the SPI communication device, and the second pin is a data pin of the SPI communication device.

[0024] In another embodiment, the serial communication device is a UART communication device, the first pin is a pin of the UART communication device having a clock rate detection function, and the second pin is a data pin of the UART communication device; the UART communication device supports a single-wire half-duplex transmission mode.

[0025] In a second aspect, the present application also provides a method for reading a Cable ID of an HDMI active cable, wherein the HDMI active cable is connected with a source device and a sink device, the source device connects an HDMI-SCL signal line and an HDMI-SDA signal line of the HDMI active cable, the sink device connects the HDMI-SCL signal line and the HDMI-SDA signal line of the HDMI active cable, and the HDMI active cable comprises a serial communication device connected with the HDMI-SCL signal line and the HDMI-SDA signal line. The method comprises: the source device and the sink device communicate with each other through a plurality of first signal sequences on the HDMI-SCL signal line and the HDMI-SDA signal line, and the serial communication device detects the plurality of first signal sequences on the HDMI-SCL signal line and the HDMI-SDA signal line; the source device and the sink device communicate with each other through a second signal sequence on the HDMI-SCL signal line and the HDMI-SDA signal line, and the serial communication device detects the second signal sequence on the HDMI-SCL signal line and the HDMI-SDA signal line; the serial communication device, in response to sequentially detecting the plurality of first signal sequences and the second signal sequence on the HDMI-SCL signal line and the HDMI-SDA signal line, outputs all or part of the Cable ID through the HDMI-SCL signal line and the HDMI-SDA signal line; wherein the data of the Cable ID starting from an offset value and having a length is output through the HDMI-SCL signal line and the HDMI-SDA signal line according to the offset value and the length obtained from the plurality of first signal sequences; the source device and the sink device communicate with each other through a third signal sequence on the HDMI-SCL signal line and the HDMI-SDA signal line, and the serial communication device detects the third signal sequence on the HDMI-SCL signal line and the HDMI-SDA signal line; and the serial communication device, in response to sequentially detecting the third signal sequence on the HDMI-SCL signal line and the HDMI-SDA signal line, identifies that the reading of the Cable ID is completed.

[0026] In a third aspect, the present application also provides a device for processing reading of a Cable ID of an HDMI active cable, which is a serial communication device, comprising: a processor configured to execute program instructions; and a memory configured to store the program instructions, which, when loaded and executed by the processor, cause the processor to execute the method according to one of the plurality of embodiments of the first aspect.

[0027] In one embodiment, the device comprises an SPI communication device, a clock pin of the SPI communication device is connected to the HDMI-SCL signal line, and a data pin of the SPI communication device is connected to the HDMI-SDA signal line.

[0028] In another embodiment, the device comprises a UART communication device, a pin with clock rate detection function of the UART communication device is connected to the HDMI-SCL signal line, and a data pin of the UART communication device is connected to the HDMI-SDA signal line; the UART communication device supports a single-wire half-duplex transmission mode.

[0029] Overall, compared with the prior art, the above technical solutions conceived by the present application can achieve the following beneficial effects: the other serial communication devices in the general MCU chip are used to replace the I2C on-chip peripherals, so that the data can be listened to and responded to on the I2C channel while meeting the non-response I2C slave address, thereby completing the CableID data reading function of the HDMI2.1 protocol. BRIEF DESCRIPTION OF DRAWINGS

[0030] The above and other objects, features and advantages of the exemplary embodiments of the present application will be more apparent from the following detailed description taken in conjunction with the accompanying drawings, in which several embodiments of the present application are shown by way of example, and wherein like reference numerals refer to like elements throughout. In the drawings:

[0031] Figure 1 An exemplary schematic diagram of an HDMI active cable device to which the present application is applied is shown;

[0032] Figure 2 An exemplary flowchart of a method for processing reading of a Cable ID for an HDMI active cable according to an embodiment of the present application is shown;

[0033] Figure 3 An exemplary diagram of a CableID data reading method is shown;

[0034] Figure 4 An exemplary flowchart of a method for reading a Cable ID of an HDMI active cable according to an embodiment of the present application is shown;

[0035] Figure 5 An exemplary schematic diagram of a device for processing reading of a Cable ID for an HDMI active cable is shown. DETAILED DESCRIPTION

[0036] The following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of them. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative work shall fall within the scope of protection of the present invention.

[0037] It should be understood that the terms "include" and "comprising" used in the description and claims of the present invention indicate the presence of described features, integers, steps, operations, elements and / or components, but do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components and / or collections thereof.

[0038] It should also be understood that the terminology used in this specification is for the purpose of describing specific embodiments only and is not intended to limit the present invention. As used in the specification and claims, the singular forms "a," "an," and "the" are intended to include the plural forms unless the context clearly indicates otherwise. It should further be understood that the term "and / or" as used in the specification and claims refers to any and all possible combinations of one or more of the associated listed items, including and including these combinations.

[0039] As used in this specification and claims, the term "if" can be interpreted as "when" or "upon" or "in response to determining" or "in response to detecting," depending on the context. Similarly, the phrase "if it is determined" or "if [described condition or event] is detected" can be interpreted as meaning "upon determination" or "in response to determining" or "upon detection of [described condition or event]" or "in response to detecting [described condition or event]," depending on the context.

[0040] The specific embodiments of the present invention will be described in detail below with reference to the accompanying drawings.

[0041] Figure 1 An exemplary schematic diagram of an HDMI active cable device 100 to which the present invention is applicable is shown.

[0042] like Figure 1As shown in the figure, the HDMI active cable device 100 may include a source device (HDMI transmitter 101 in the figure), a slave device (HDMI receiver 102 in the figure), a TX module 103 and an RX module 104. The source device may include a host, and the slave device may include a terminal device such as a display. The source device 101 and the slave device 102 are connected via the HDMI-SCL signal line 105 and the HDMI-SDA signal line 106 of the HDMI active cable, respectively, to transmit clock signals and I2C data. The TX module 103 can be located in the source device, and the RX module can be located in the slave device 102. The high-speed signal processing circuit in the TX module 103 and the high-speed signal processing circuit in the RX module 104 are connected via a high-speed media data line to transmit high-speed signals. The TX module 103 may also include a Cable ID processing module. The Cable ID processing module may include an MCU and a serial communication device 1032 located therein. The Cable ID processing module can be used to monitor the clock signal and I2C data to read and process the CableID data.

[0043] The present invention will be described in detail below with reference to the structure of the above-mentioned HDMI active cable device 100 .

[0044] Figure 2 FIG. 2 is a flow chart illustrating an exemplary method 200 for processing Cable ID reading for an HDMI active cable according to an embodiment of the present invention.

[0045] like Figure 2 As shown in , the method 200 may include, at step S201, monitoring the HDMI-SCL signal line and the HDMI-SDA signal line of the HDMI active cable using a serial communication device, wherein the serial communication device includes a first pin and a second pin, the first pin is connected to the HDMI-SCL signal line, and the second pin is connected to the HDMI-SDA signal line. It is understood that the CableID processing module may include a serial communication device, such as Figure 1 Serial communication device 1032 in.

[0046] In one implementation, the serial communication device may be a SPI (Serial Peripheral Interface) communication device, the first pin may be a clock pin of the SPI communication device, such as SPI_SCK of the SPI communication device; and the second pin may be a data pin of the SPI communication device.

[0047] In another implementation, the serial communication device may be a UART communication device, the first pin may be a pin of the UART communication device with a clock rate detection function, and the second pin may be a data pin of the UART communication device; the UART communication device may support a single-line half-duplex transmission mode. It is understood that in addition to the above two devices, other serial communication devices are also within the scope of protection of the present invention and are not listed here.

[0048] The clock signal on the HDMI-SCL signal line and the data signal on the HDMI-SDA signal line can be monitored by connecting the serial communication device to the HDMI-SCL signal line and the HDMI-SDA signal line.

[0049] According to the IDCC protocol, a CableID read operation consists of several complete I2C read operations. The CableID data structure consists of three parts: Header, Payload, and Checksum. Figure 3 An example diagram of a CableID data reading method 300 is shown. The upper table in the figure shows the data reading process of the Header portion of the CableID, and the lower table shows the data reading process of the Payload and Checksum portions of the CableID. In the figure, each data transmission is performed in ascending order of the number. For example, for Header-Marker1, data is transmitted in the order of 1, 2, 3...11. In addition, the "source device" with a dotted fill in the upper right corner indicates that the data in the dotted cell in the table is transmitted by the source device, the "slave device" with a slash fill in the cell indicates that the data in the slash fill in the cell in the table is transmitted by the slave device, and the "cable" with no fill in the cell indicates that the data in the no fill in the cell in the table is transmitted by the cable.

[0050] like Figure 3 As shown in the table above, the Header part includes Maker1-Maker2-Maker3-Offset (the offset value of the read data, and the data reading starts from the position corresponding to the offset value)-Length (the length of the read data), which is completed by 5 complete I2C read operations. In this read operation, the source device sends the data, and the serial communication device only listens to the data. Figure 3 As shown in the table below, the payload portion is completed by a complete I2C read operation. In this read operation, the source device sends data, and the serial communication device listens and responds to the data.

[0051] Based on this, at step S202, the serial communication device, in response to sequentially detecting a plurality of first signal sequences and a second signal sequence on the HDMI-SCL signal line and the HDMI-SDA signal line, can output all or part of the Cable ID through the HDMI-SCL signal line and the HDMI-SDA signal line; wherein the data of the Cable ID starting from the offset value and having the length is determined according to the offset value (Offset) and the length (Length) obtained from the plurality of first signal sequences. The value of Offset can be 1, 2, 3, 4, etc., and the length of Length can be 1, 2, 3, 4, etc., which is not limited in the embodiment.

[0052] Based on the data transmission process of the Header part described above, the plurality of first signal sequences can include five first signal sequences (as shown in Figure 3 , "A1" represents the first first signal sequence, "A2" represents the second first signal sequence, "A3" represents the third first signal sequence, "A4" represents the fourth first signal sequence, and "A5" represents the fifth first signal sequence). Figure 3 As shown in Figure 3 , each first signal sequence can include an I2C start signal, an I2C address 0xA0, an I2C ACK (Acknowledge) signal, I2C data, an I2C ACK signal, an I2C restart signal, an I2C address 0xA1, an I2C ACK signal, I2C data EDID, an I2C NACK signal, and an I2C stop signal, which appear in sequence.

[0053] Based on the data transmission process of the Header part described above, Figure 3 , the data in the 4th transmission bit (i.e. the cell labeled 4) of the Header part table is the I2C data in the first signal sequence. As shown in the figure, the I2C data of the first first signal sequence of the plurality of first signal sequences can be 0xAE, the I2C data of the second first signal sequence of the plurality of first signal sequences can be 0x6E, the I2C data of the third first signal sequence of the plurality of first signal sequences can be 0x61, the I2C data of the fourth first signal sequence of the plurality of first signal sequences can be the offset value Offset, and the I2C data of the fifth first signal sequence of the plurality of first signal sequences can be the length Length, wherein Length is the value of the length. The 0xAE is the Cable ID data structure flag 1, 0x6E is the Cable ID data structure flag 2, and 0x61 is the Cable ID data structure flag 3.

[0054] In one embodiment, each signal or data in the first signal sequence described above can be generated by driving of a clock signal, and based on this, detecting the first signal sequence on the HDMI-SCL signal line and the HDMI-SDA signal line can include:

[0055] According to the occurrence of a high level on the HDMI-SCL signal line, detecting a falling edge on the HDMI-SDA signal line, it is identified that the I2C start signal occurs;

[0056] According to the occurrence of a high level on the HDMI-SCL signal line, detecting a falling edge on the HDMI-SDA signal line, it is identified that the I2C start signal occurs;

[0057] According to the occurrence of a high level on the HDMI-SCL signal line, detecting a falling edge on the HDMI-SDA signal line, it is identified that the I2C start signal occurs;

[0058] According to the occurrence of a high level on the HDMI-SCL signal line, detecting a falling edge on the HDMI-SDA signal line, it is identified that the I2C start signal occurs; the I2C data corresponds to one of "0XAE", "0x6E", "0x61", "Offset" and "Length" described above, i.e. when detecting the first first signal sequence, the I2C data is "0XAE", when detecting the second first signal sequence, the I2C data is "0x6E", when detecting the third first signal sequence, the I2C data is "0x61", when detecting the fourth first signal sequence, the I2C data is "Offset", and when detecting the fifth first signal sequence, the I2C data is "Length".

[0059] According to the occurrence of a high level on the HDMI-SCL signal line, detecting a falling edge on the HDMI-SDA signal line, it is identified that the I2C start signal occurs;

[0060] According to the occurrence of a high level on the HDMI-SCL signal line, detecting a falling edge on the HDMI-SDA signal line, it is identified that the I2C start signal occurs;

[0061] According to the occurrence of a high level on the HDMI-SCL signal line, detecting a falling edge on the HDMI-SDA signal line, it is identified that the I2C start signal occurs;

[0062] According to the occurrence of a high level on the HDMI-SCL signal line, detecting a falling edge on the HDMI-SDA signal line, it is identified that the I2C start signal occurs;

[0063] According to the clock drive on the HDMI-SCL signal line, one byte of I2C data EDID is received on the HDMI-SDA signal line, and the presence of I2C data EDID is recognized;

[0064] When a high level is detected on the HDMI-SDA signal line under the next clock drive on the HDMI-SCL signal line, an I2C NACK signal is identified;

[0065] When a high level appears on the HDMI-SCL signal line, a rising edge is detected on the HDMI-SDA signal line, thereby recognizing the presence of an I2C stop signal.

[0066] In one embodiment, the second signal sequence ( Figure 3 The “B” in FIG. 2 represents a second signal sequence) may include an I2C start signal, an I2C address 0xA0, an I2C ACK signal, I2C data 0x01, an I2C ACK signal, an I2C restart signal, an I2C address 0xA1, and an I2C ACK signal that appear in sequence.

[0067] Similar to the detection of the first signal sequence above, each signal or data in the second signal sequence can also be generated by driving the clock signal. Therefore, detecting the second signal sequence on the HDMI-SCL signal line and the HDMI-SDA signal line may include:

[0068] When a high level appears on the HDMI-SCL signal line, a falling edge is detected on the HDMI-SDA signal line, and the presence of an I2C start signal is recognized;

[0069] According to the clock drive on the HDMI-SCL signal line, data 0xA0 is received on the HDMI-SDA signal line, and the I2C address 0xA0 is recognized;

[0070] When a low level is detected on the HDMI-SDA signal line under the next clock drive on the HDMI-SCL signal line, the I2C ACK signal is recognized;

[0071] According to the clock drive on the HDMI-SCL signal line, the I2C data 0x01 is received on the HDMI-SDA signal line, and the I2C data 0x01 is recognized;

[0072] When a low level is detected on the HDMI-SDA signal line under the next clock drive on the HDMI-SCL signal line, the I2C ACK signal is recognized;

[0073] According to the detection of a falling edge on the HDMI-SDA signal line when a high level appears on the HDMI-SCL signal line, it is identified that the I2C resume signal appears;

[0074] According to the reception of data 0xA1 on the HDMI-SDA signal line under the clock driving on the HDMI-SCL signal line, it is identified that the I2C address 0xA1 appears;

[0075] According to the detection of a low level on the HDMI-SDA signal line under the next clock driving on the HDMI-SCL signal line, it is identified that the I2C ACK signal appears.

[0076] Similarly, the relationship between the high and low levels of the clock signal and the corresponding signal or data can be modified as needed, for example, according to the detection of a rising edge on the HDMI-SDA signal line when a low level appears on the HDMI-SCL signal line, it is identified that the I2C start signal appears; according to the detection of a high level on the HDMI-SDA signal line under the next clock driving on the HDMI-SCL signal line, it is identified that the I2C ACK signal appears.

[0077] In one implementation scenario, the data output through the HDMI-SCL signal line and the HDMI-SDA signal line from the offset value of the Cable ID and having a length can include: outputting a plurality of fourth signal sequences through the HDMI-SCL signal line and the HDMI-SDA signal line. Each fourth signal sequence can include one byte of the Cable ID. Based on this, the number of fourth signal sequences can be equal to the length. The I2C data of the first fourth signal sequence can be the first byte of the Cable ID, the I2C data of the second fourth signal sequence can be the second byte of the Cable ID, and so on, the I2C data of the Lengthth fourth signal sequence is the Lengthth byte of the Cable ID, where Length is the numerical value of the length. As an example, Figure 3 The output of N Cable ID bytes is shown in FIG. 4, that is, including N fourth sequences, N is a positive integer greater than 1, for example, 3 or 4. In Figure 3 In FIG. 4, “C1” represents the first fourth signal sequence, and “Cn” represents the Nth fourth signal sequence. It can be understood that the fourth signal sequence also includes a checksum, which is used for verification to determine whether the data transmission is correct, Length is the number of Cable-ID data structures to be read by the source device, and the number of fourth signal sequences is Length+1. It should be noted that in this embodiment, the fourth signal sequence does not include the “ACK” signal after each “Cable ID Byte”.

[0078] In the embodiment, the transmission of the fourth signal sequence can also be based on the driving of the clock signal. Based on this, the output of the fourth signal sequence through the HDMI-SCL signal line and the HDMI-SDA signal line can include:

[0079] According to the clock driving on the HDMI-SCL signal line, one byte data of the Cable ID is output through the HDMI-SDA signal line, wherein the byte data is located at an offset of the starting position of the Cable ID, and the offset is the above-mentioned offset value plus m minus 1, wherein the currently output fourth signal sequence is the mth fourth signal sequence in the plurality of fourth signal sequences, and m is a positive integer greater than or equal to 1, for example, 1, 2, 3, 4, etc. Figure 3 For example, when m is 1, the first byte of the Cable ID, i.e., Cable ID Byte1, is output through the HDMI-SDA signal line; when m is 2, the second byte of the Cable ID, i.e., Cable ID Byte2, is output through the HDMI-SDA signal line.

[0080] When the Cable ID data is transmitted, whether the next byte data is continuously transmitted can be determined based on whether the response signal transmitted by the source device is detected after one byte data of the Cable ID is transmitted, so as to determine the reliable transmission of each I2C data. Based on this, in one embodiment, after one fourth signal sequence is output through the HDMI-SCL signal line and the HDMI-SDA signal line, the next fourth signal sequence is output through the HDMI-SCL signal line and the HDMI-SDA signal line in response to the detection of the I2C ACK signal (the “ACK signal” behind each Cable ID in the lower part of the table) from the HDMI-SCL signal line and the HDMI-SDA signal line. Figure 3 For example, in the embodiment, after the first fourth signal sequence C1 is transmitted, the ACK signal (the ACK signal corresponding to the label 10) transmitted by the source device is detected, and then the second fourth signal sequence is output. That is, after one I2C data is transmitted by the cable, a response signal is generated by the source device, so as to determine that the transmission of the I2C data is completed. Through the data transmission mode, the reliable reading of all I2C data can be ensured. Figure 3

[0081] Similarly to the principle of the detection signal described above, the detection of the I2C ACK signal from the HDMI-SCL signal line and the HDMI-SDA signal line can include: when a low level is detected on the HDMI-SDA signal line according to the next clock driving on the HDMI-SCL signal line, it is recognized that the I2C ACK signal appears.

[0082] ​The scheme can also determine that the processing of reading the Cable ID is completed when another signal sequence is detected, so as to determine that the I2C data transmission of the cable ends, that is, the entire I2C data reading process ends. Based on this, at step S203, the serial communication device, in response to detecting the third signal sequence (such as "D" in Figure 3 ) on the HDMI-SCL signal line and the HDMI-SDA signal line in turn, identifies that the processing of reading the Cable ID is completed.

[0083] As shown in Figure 4 , detecting the third signal sequence on the HDMI-SCL signal line and the HDMI-SDA signal line can include:

[0084] According to the next clock driving on the HDMI-SCL signal line, when a high level is detected on the HDMI-SDA signal line, it is identified that the I2C NACK signal appears;

[0085] According to the appearance of a high level on the HDMI-SCL signal line, when a rising edge is detected on the HDMI-SDA signal line, it is identified that the I2C stop signal appears.

[0086] The scheme uses the NACK signal and the I2C stop signal transmitted by the source device to mark the end of the Cable ID reading process.

[0087] As can be known from the description of the above embodiments, the application uses other serial communication devices in the general MCU chip to replace the I2C on-chip peripheral, so that the data can be listened to and responded to on the I2C channel while meeting the requirement of not responding to the I2C slave address, thereby completing the Cable ID data reading function of the HDMI2.1 protocol.

[0088] Figure 1 An exemplary flowchart of a method 400 of reading the Cable ID of an HDMI active cable according to an embodiment of the application is shown.

[0089] As shown in Figure 1 , the HDMI active cable source device is connected with the slave device, the source device is connected with the HDMI-SCL signal line 105 and the HDMI-SDA signal line 106 of the HDMI active cable, the slave device is connected with the HDMI-SCL signal line 105 and the HDMI-SDA signal line 106 of the HDMI active cable, the HDMI active cable includes a serial communication device 1032, and the serial communication device 102 is connected with the HDMI-SCL signal line 105 and the HDMI-SDA signal line 106 of the HDMI active cable. The structure of the device and the like can be referred to the description of the above-mentioned Figure 4 , which will not be described in detail here.

[0090] AsFigure 5 As shown in the method 400 can comprise at step S401, the source device and the sink device communicate through a plurality of first signal sequences on the HDMI-SCL signal line and the HDMI-SDA signal line, the serial communication device can detect the plurality of first signal sequences on the HDMI-SCL signal line and the HDMI-SDA signal line.

[0091] Then, at step S402, the source device and the sink device communicate through a second signal sequence on the HDMI-SCL signal line and the HDMI-SDA signal line, the serial communication device can detect the second signal sequence on the HDMI-SCL signal line and the HDMI-SDA signal line.

[0092] At step S403, the serial communication device, in response to sequentially detecting the plurality of first signal sequences and the second signal sequence on the HDMI-SCL signal line and the HDMI-SDA signal line, can output all or part of the Cable ID through the HDMI-SCL signal line and the HDMI-SDA signal line; wherein the data of the Cable ID starting from the offset value and having the length is output through the HDMI-SCL signal line and the HDMI-SDA signal line according to the offset value and the length obtained from the plurality of first signal sequences.

[0093] At step S404, the source device and the sink device communicate through a third signal sequence on the HDMI-SCL signal line and the HDMI-SDA signal line, the serial communication device can detect the third signal sequence on the HDMI-SCL signal line and the HDMI-SDA signal line.

[0094] At step S405, the serial communication device, in response to sequentially detecting the third signal sequence on the HDMI-SCL signal line and the HDMI-SDA signal line, can identify that the processing of reading the Cable ID is completed.

[0095] The detailed process of the present scheme and the like can be referred to the foregoing description of the method for processing reading of the Cable ID for the HDMI active cable, which will not be described in detail here.

[0096] According to the foregoing description of the method for processing reading of the Cable ID for the HDMI active cable, it can be known that the present application replaces the I2C on-chip peripheral with other serial communication devices in the general MCU, so that the I2C slave address is not responded to, and data can be listened to and responded to on the I2C channel, thereby completing the Cable ID data reading function of the HDMI2.1 protocol.

[0097] The method of reading the Cable ID of the HDMI active cable is described above in combination with the embodiments, and the device for processing the reading of the Cable ID for the HDMI active cable will be described below in combination with Figure 5 the HDMI active cable.

[0098] Figure 5 An exemplary schematic diagram of a device 500 for processing the reading of the Cable ID for the HDMI active cable is shown.

[0099] As shown in the HDMI active cable. ​ The device 500 can be a serial communication device, which can include a processor 501 and a memory 502, and the processor 501 and the memory 502 communicate with each other through a bus 503. The processor 501 can be configured to execute program instructions, and the memory 502 can be configured to store the above-mentioned program instructions, which, when loaded and executed by the processor 501, cause the processor 501 to perform the method according to any one of the embodiments of the method for processing the reading of the Cable ID for the HDMI active cable described above.

[0100] In one embodiment, the above-mentioned device 500 can include an SPI communication device, the clock pin of the SPI communication device is connected to the HDMI-SCL signal line, and the data pin of the SPI communication device is connected to the HDMI-SDA signal line.

[0101] In another embodiment, the above-mentioned device 500 can further include a UART communication device, the pin with clock rate detection function of the UART communication device is connected to the HDMI-SCL signal line, and the data pin of the UART communication device is connected to the HDMI-SDA signal line; the UART communication device supports single-wire half-duplex transmission mode.

[0102] According to the description of the method for processing the reading of the Cable ID for the HDMI active cable described above, the device 500 of the present application can use other serial communication devices in the general MCU chip to replace the I2C on-chip peripheral, so as to meet the non-response I2C slave address while listening and responding to data on the I2C channel, thereby completing the Cable ID data reading function of the HDMI2.1 protocol.

[0103] It should be understood that the terms "first", "second", "third", and "fourth" and the like in the description and in the claims of the present application are used for distinguishing between similar objects and not necessarily for describing a particular sequential or chronological order. The terms "comprises", "comprising", "includes", "including" and the like means "including, but not limited to" and indicates the presence of what is mentioned but not to the exclusion of one or more additional objects, integers, steps, operations, elements, components and / or groups thereof.

[0104] While several embodiments of the application have been shown and described herein, it is obvious that many changes and modifications can be made thereto without departing from the ideological and spiritual scope of the application. It is also to be understood that various substitutions, modifications and changes can be made by those skilled in the art in practicing the present application. The accompanying claims are intended to define the scope of the protection of the present application and thus cover equivalent or alternative solutions within the scope of these claims.

Claims

1. A method for processing an HDMI active cable and reading a Cable ID based on the IDCC protocol, characterized in that: The method comprises: Using a serial communication device to monitor the HDMI-SCL signal line and the HDMI-SDA signal line of the HDMI active cable, wherein the serial communication device includes a first pin and a second pin, the first pin is connected to the HDMI-SCL signal line, and the second pin is connected to the HDMI-SDA signal line; The serial communication device, in response to sequentially detecting a plurality of first signal sequences and a second signal sequence on the HDMI-SCL signal line and the HDMI-SDA signal line, outputs all or part of the Cable ID through the HDMI-SCL signal line and the HDMI-SDA signal line; wherein data of the Cable ID starting from the offset value and having the length to be output through the HDMI-SCL signal line and the HDMI-SDA signal line is determined based on the offset values ​​and lengths obtained from the plurality of first signal sequences; The serial communication device recognizes that the reading of the Cable ID is completed in response to detecting a third signal sequence in sequence on the HDMI-SCL signal line and the HDMI-SDA signal line.

2. The method according to claim 1, wherein The first signal sequence includes an I2C start signal, an I2C address 0xA0, an I2C ACK signal, I2C data, an I2C ACK signal, an I2C restart signal, an I2C address 0xA1, an I2C ACK signal, an I2C data EDID, an I2C NACK signal, and an I2C stop signal that appear in sequence.

3. The method according to claim 1 or 2, characterized in that The plurality of first signal sequences include five first signal sequences.

4. The method according to claim 3, characterized in that The I2C data of the first first signal sequence of the multiple first signal sequences is 0xAE, the I2C data of the second first signal sequence of the multiple first signal sequences is 0x6E, the I2C data of the third first signal sequence of the multiple first signal sequences is 0x61, the I2C data of the fourth first signal sequence of the multiple first signal sequences is the offset value Offset, and the I2C data of the fifth first signal sequence of the multiple first signal sequences is the length Length, where Length is the numerical value of the length.

5. The method according to any one of claims 1 to 4, characterized in that The second signal sequence includes an I2C start signal, an I2C address 0xA0, an I2C ACK signal, I2C data 0x01, an I2C ACK signal, an I2C restart signal, an I2C address 0xA1, and an I2C ACK signal that appear in sequence.

6. The method according to any one of claims 1 to 5, characterized in that Outputting data of the Cable ID starting from the offset value and having the length through the HDMI-SCL signal line and the HDMI-SDA signal line includes: outputting multiple fourth signal sequences through the HDMI-SCL signal line and the HDMI-SDA signal line.

7. The method according to claim 6, wherein The fourth signal sequence includes one-byte data of Cable ID.

8. The method according to claim 6 or 7, characterized in that The number of the fourth signal sequences is equal to the length.

9. The method according to claim 8, wherein The I2C data of the first fourth signal sequence is the first byte of CableID, the I2C data of the second fourth signal sequence is the second byte of CableID, ..., the I2C data of the Lengthth fourth signal sequence is the Lengthth byte of CableID, where Length is the value of the length.

10. The method according to any one of claims 6 to 9, characterized in that in, After outputting a fourth signal sequence through the HDMI-SCL signal line and the HDMI-SDA signal line, in response to detecting an I2C ACK signal from the HDMI-SCL signal line and the HDMI-SDA signal line, the next fourth signal sequence is output through the HDMI-SCL signal line and the HDMI-SDA signal line.

11. The method according to claim 2, characterized in that Detecting a first signal sequence on the HDMI-SCL signal line and the HDMI-SDA signal line includes: According to detecting a falling edge on the HDMI-SDA signal line when a high level appears on the HDMI-SCL signal line, identifying the presence of the I2C start signal; According to the clock driving on the HDMI-SCL signal line, data 0xA0 is received on the HDMI-SDA signal line, and the I2C address 0xA0 is identified; Recognizing the presence of an I2C ACK signal when a low level is detected on the HDMI-SDA signal line under the next clock drive on the HDMI-SCL signal line; Receiving I2C data on the HDMI-SDA signal line under the clock drive on the HDMI-SCL signal line, identifying the presence of I2C data; Recognizing the presence of an I2C ACK signal when a low level is detected on the HDMI-SDA signal line under the next clock drive on the HDMI-SCL signal line; According to detecting a falling edge on the HDMI-SDA signal line when a high level appears on the HDMI-SCL signal line, identifying the presence of the I2C restart signal; According to the clock drive on the HDMI-SCL signal line, data 0xA1 is received on the HDMI-SDA signal line, and the I2C address 0xA1 is identified; Recognizing the presence of an I2C ACK signal when a low level is detected on the HDMI-SDA signal line under the next clock drive on the HDMI-SCL signal line; Receiving one byte of I2C data EDID on the HDMI-SDA signal line under the clock drive on the HDMI-SCL signal line, identifying the presence of the I2C data EDID; When a high level is detected on the HDMI-SDA signal line under the next clock drive on the HDMI-SCL signal line, identifying the presence of the I2C NACK signal; The occurrence of the I2C stop signal is recognized based on detecting a rising edge on the HDMI-SDA signal line when a high level appears on the HDMI-SCL signal line.

12. The method according to claim 5 or 11, characterized in that Detecting a second signal sequence on the HDMI-SCL signal line and the HDMI-SDA signal line includes: According to detecting a falling edge on the HDMI-SDA signal line when a high level appears on the HDMI-SCL signal line, identifying the presence of the I2C start signal; According to the clock driving on the HDMI-SCL signal line, data 0xA0 is received on the HDMI-SDA signal line, and the I2C address 0xA0 is identified; Recognizing the presence of an I2C ACK signal when a low level is detected on the HDMI-SDA signal line under the next clock drive on the HDMI-SCL signal line; According to the clock driving on the HDMI-SCL signal line, I2C data 0x01 is received on the HDMI-SDA signal line, and the I2C data 0x01 is identified; Recognizing the presence of an I2C ACK signal when a low level is detected on the HDMI-SDA signal line under the next clock drive on the HDMI-SCL signal line; According to detecting a falling edge on the HDMI-SDA signal line when a high level appears on the HDMI-SCL signal line, identifying the presence of the I2C restart signal; According to the clock drive on the HDMI-SCL signal line, data 0xA1 is received on the HDMI-SDA signal line, and the I2C address 0xA1 is identified; When a low level is detected on the HDMI-SDA signal line under the next clock drive on the HDMI-SCL signal line, it is recognized that an I2C ACK signal occurs.

13. The method according to any one of claims 1 to 12, characterized in that: Detecting a third signal sequence on the HDMI-SCL signal line and the HDMI-SDA signal line includes: When a high level is detected on the HDMI-SDA signal line under the next clock drive on the HDMI-SCL signal line, identifying the presence of an I2C NACK signal; According to detecting a rising edge on the HDMI-SDA signal line when a high level appears on the HDMI-SCL signal line, it is recognized that an I2C stop signal appears.

14. The method according to claim 7, wherein: Outputting a fourth signal sequence through the HDMI-SCL signal line and the HDMI-SDA signal line includes: Driven by the clock on the HDMI-SCL signal line, one-byte data of the Cable ID is output through the HDMI-SDA signal line, wherein the offset of the one-byte data from the starting position of the Cable ID is the offset value plus m minus 1, wherein the fourth signal sequence currently output is the mth fourth signal sequence among the multiple fourth signal sequences, and m is a positive integer greater than or equal to 1.

15. The method according to claim 10, wherein Detecting an I2C ACK signal from the HDMI-SCL signal line and the HDMI-SDA signal line, comprising: The presence of the I2C ACK signal is recognized when a low level is detected on the HDMI-SDA signal line under the next clock drive on the HDMI-SCL signal line.

16. The method according to any one of claims 1 to 15, characterized in that: The serial communication device is an SPI communication device, the first pin is a clock pin of the SPI communication device, and the second pin is a data pin of the SPI communication device.

17. The method according to any one of claims 1 to 15, characterized in that: The serial communication device is a UART communication device, the first pin is a pin of the UART communication device with a clock rate detection function, and the second pin is a data pin of the UART communication device; the UART communication device supports a single-line half-duplex transmission mode.

18. A method for reading the Cable ID of an HDMI active cable based on the IDCC protocol, characterized in that: The HDMI active cable is connected to a source device and a slave device, the source device is connected to an HDMI-SCL signal line and an HDMI-SDA signal line of the HDMI active cable, the slave device is connected to an HDMI-SCL signal line and an HDMI-SDA signal line of the HDMI active cable, the HDMI active cable includes a serial communication device, and the serial communication device is connected to the HDMI-SCL signal line and the HDMI-SDA signal line of the HDMI active cable; The method comprises: The source device and the slave device communicate via a plurality of first signal sequences on the HDMI-SCL signal line and the HDMI-SDA signal line, and the serial communication device detects the plurality of first signal sequences on the HDMI-SCL signal line and the HDMI-SDA signal line; The source device and the slave device communicate via a second signal sequence on the HDMI-SCL signal line and the HDMI-SDA signal line, and the serial communication device detects the second signal sequence on the HDMI-SCL signal line and the HDMI-SDA signal line; The serial communication device, in response to sequentially detecting a plurality of first signal sequences and a second signal sequence on the HDMI-SCL signal line and the HDMI-SDA signal line, outputs all or part of the Cable ID through the HDMI-SCL signal line and the HDMI-SDA signal line; wherein data of the Cable ID starting from the offset value and having the length to be output through the HDMI-SCL signal line and the HDMI-SDA signal line is determined based on the offset values ​​and lengths obtained from the plurality of first signal sequences; The source device and the slave device communicate via a third signal sequence on the HDMI-SCL signal line and the HDMI-SDA signal line, and the serial communication device detects the third signal sequence on the HDMI-SCL signal line and the HDMI-SDA signal line; The serial communication device recognizes that the reading of the Cable ID is completed in response to detecting a third signal sequence in sequence on the HDMI-SCL signal line and the HDMI-SDA signal line.

19. A device for processing an HDMI active cable to read a Cable ID based on the IDCC protocol, the device being a serial communication device, characterized in that: include: a processor configured to execute program instructions; as well as A memory configured to store the program instructions, which, when loaded and executed by the processor, causes the processor to perform the method according to any one of claims 1 to 17.

20. The device according to claim 19, characterized in that The device includes an SPI communication device, a clock pin of the SPI communication device is connected to the HDMI-SCL signal line, and a data pin of the SPI communication device is connected to the HDMI-SDA signal line.

21. The device according to claim 19, characterized in that The device includes a UART communication device, a pin of the UART communication device with a clock rate detection function is connected to the HDMI-SCL signal line, and a data pin of the UART communication device is connected to the HDMI-SDA signal line; and the UART communication device supports a single-line half-duplex transmission mode.

Images