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[ADV7480] About laptop audio output

Category: Software

Hi,

We are evaluating the ADV780 product.

I am checking the video/audio output by connecting the HDMI output of a Windows 10 laptop (Dynabook R73)

to a monitor equipped with ADV7480.

The video from the PC is output, but the audio from the PC is not output.

(PC audio driver itself does not recognize)

What could be the cause?

For monitors without ADV7480, PC audio is output.

Best regards.

Parents
  • Hi Tatsuya San,

      Please note that,by using Consumer electronic equipment or PCs as an HDMI audio/video source can be very difficult since their functionality depends on their settings as well as the HDMI receiver's EDID

      For example everything depends on the source.  If the source doesn't get a valid EDID it may just begin transmitting in DVI mode with no audio and no HDCP.

     Please verify your EDID data supports Audio Since source output can change based on EDID data provided.

     Can you please inform customers to use a DVI/HDMI generator (such as Quantum Data/Astro) in order to test digital audio over HDMI. Please check with ASTRO equipment.

    Thanks,

    Poornima

  • Hi,

    Thank you for your reply.

    In the past, I was able to output video and audio from a Windows 10 laptop

    using HDMI receivers from other manufacturers.

    This time, I am using the same PC and ADV7480 as at that time,

    but the video is output, but the audio is not.

    The difference in EDID settings is Product ID, year of manufacture, EDID Revision,

    and check Sum.

    Is there any other possible cause other than EDID?

    Best regards.

  • Hi Tatsuya San,

            Could you please share your EDID bytes, We will check it and let you know the status.

    Thanks,

    Poornima

  • Hi,

    Thank you for your reply.

    The EDID setting list is attached below.

    XLSX

    Best regards.

  • Hi Tatsuya San,

            It seems your corresponding EDID would support only LPCM audio.

            Please let us know, the audio stream that you are playing from the laptop.

            Also Please note sometimes PC has failed to get the correct EDID, So toggle the HPA line to force the PC to re-read the EDID and follow either below two sequence,

           This must be done after the EDID is loaded.

    1) Set HPA_MAN_VALUE_A = 1 ; sets bit high

    2) HPA_TRISTATE_A = 0 ;  make HPA pin an output

    3) set HPA_MAN_VALUE = 0 ; Pulls HPA pin low

    4) wait 100ms ; just delay a bit

    5) set HPA_TRISTATE = 1 ; makes HPA pin an input

    6) External pull up resistor will create the rising edge on the HPD  causing the PC to re-read the EDID

    Or

    1) HPA_MAN_VALUE_X =1

    2) HPA_A pin active =0

    3)  HPA_MAN_VALUE_A =0, sets HPA low

    4)  load up the EDID

    5) HPA_MAN_VALUE_A =1, sets HPA high, forces source to reload EDID

       

    Thanks,

    Poornima

  • Hi,

    Sorry for the late thank you.

    Thank you for your reply.

    I have additional questions.

    Q1) Can the above sequence be executed from the HPD=H state?

    Q2) In the above sequence, is the following correct register setting procedure

           for the ADV7480 device?

          1) Set HPA_MAN_VALUE_A = 1 ; sets bit high     

          2) HPA_TRISTATE_A = 0 ; make HPA pin an output

          3) set HPA_MAN_VALUE = 0 ; Pulls HPA pin low

          4) wait 100ms ; just delay a bit

          5) set HPA_TRISTATE = 1 ; makes HPA pin an input     

        ↓

          1) HDMI Rx-MAP(0x68) Register Addr(0xF8) Data (0x01)

          2) HDMI Rx-MAP(0x68) Register Addr(0xF9) Data (0x00)

          3) HDMI Rx-MAP(0x68) Register Addr(0xF8) Data (0x00)

          4) 100ms wait

          5) HDMI Rx-MAP(0x68) Register Addr(0xF9) Data (0x01)

     Or
          1) HPA_MAN_VALUE_X=1

          2) HPA_A pin active =0

          3) HPA_MAN_VALUE_A =0, sets HPA low

          4) load up the EDID

          5) HPA_MAN_VALUE_A =1, sets HPA high, forces source to reload EDID

                 ↓

          1) HDMI Rx-MAP(0x68) Register Addr(0x6C) Data (0x01)

          2) HDMI Rx-MAP(0x68) Register Addr(0xF9) Data (0x00)

          3) HDMI Rx-MAP(0x68) Register Addr(0xF8) Data (0x00)

          4) ??

          5) HDMI Rx-MAP(0x68) Register Addr(0xF8) Data (0x01)

          How can we control "4)"?

    Best regards.

  • Hi Tatsuya San,

    Please find the below comments,

     Q1) Can the above sequence be executed from the HPD=H state?

    YES, the sequence should be executed from HPD High state.

    Please note When the sink toggles the HPA line low then high, It tells the source to read the EDID data.  Normally with source will not read the EDID until it sees a low to high transition( By spec, the low to high HPD transition should cause the source to read the EDID). 

    Q2) How can we control "4)"?

    Please configure the below EDID in your script.

    And this CEA write would indicate the CEA tag is present "6C 80 02" .

    64 74 00 ; Disable the Internal EDID for all ports

    6C 00 00 ;

    6C 01 FF ;

    6C 02 FF ;

    6C 03 FF ;

    6C 04 FF ;

    6C 05 FF ;

    6C 06 FF ;

    6C 07 00 ;

    6C 08 06 ;

    6C 09 8F ;

    6C 0A 07 ;

    6C 0B 11 ;

    6C 0C 01 ;

    6C 0D 00 ;

    6C 0E 00 ;

    6C 0F 00 ;

    6C 10 17 ;

    6C 11 11 ;

    6C 12 01 ;

    6C 13 03 ;

    6C 14 80 ;

    6C 15 0C ;

    6C 16 09 ;

    6C 17 78 ;

    6C 18 0A ;

    6C 19 1E ;

    6C 1A AC ;

    6C 1B 98 ;

    6C 1C 59 ;

    6C 1D 56 ;

    6C 1E 85 ;

    6C 1F 28 ;

    6C 20 29 ;

    6C 21 52 ;

    6C 22 57 ;

    6C 23 00 ;

    6C 24 00 ;

    6C 25 00 ;

    6C 26 01 ;

    6C 27 01 ;

    6C 28 01 ;

    6C 29 01 ;

    6C 2A 01 ;

    6C 2B 01 ;

    6C 2C 01 ;

    6C 2D 01 ;

    6C 2E 01 ;

    6C 2F 01 ;

    6C 30 01 ;

    6C 31 01 ;

    6C 32 01 ;

    6C 33 01 ;

    6C 34 01 ;

    6C 35 01 ;

    6C 36 8C ;

    6C 37 0A ;

    6C 38 D0 ;

    6C 39 8A ;

    6C 3A 20 ;

    6C 3B E0 ;

    6C 3C 2D ;

    6C 3D 10 ;

    6C 3E 10 ;

    6C 3F 3E ;

    6C 40 96 ;

    6C 41 00 ;

    6C 42 81 ;

    6C 43 60 ;

    6C 44 00 ;

    6C 45 00 ;

    6C 46 00 ;

    6C 47 18 ;

    6C 48 01 ;

    6C 49 1D ;

    6C 4A 80 ;

    6C 4B 18 ;

    6C 4C 71 ;

    6C 4D 1C ;

    6C 4E 16 ;

    6C 4F 20 ;

    6C 50 58 ;

    6C 51 2C ;

    6C 52 25 ;

    6C 53 00 ;

    6C 54 81 ;

    6C 55 49 ;

    6C 56 00 ;

    6C 57 00 ;

    6C 58 00 ;

    6C 59 9E ;

    6C 5A 00 ;

    6C 5B 00 ;

    6C 5C 00 ;

    6C 5D FC ;

    6C 5E 00 ;

    6C 5F 56 ;

    6C 60 41 ;

    6C 61 2D ;

    6C 62 31 ;

    6C 63 38 ;

    6C 64 30 ;

    6C 65 39 ;

    6C 66 41 ;

    6C 67 0A ;

    6C 68 20 ;

    6C 69 20 ;

    6C 6A 20 ;

    6C 6B 20 ;

    6C 6C 00 ;

    6C 6D 00 ;

    6C 6E 00 ;

    6C 6F FD ;

    6C 70 00 ;

    6C 71 17 ;

    6C 72 3D ;

    6C 73 0D ;

    6C 74 2E ;

    6C 75 11 ;

    6C 76 00 ;

    6C 77 0A ;

    6C 78 20 ;

    6C 79 20 ;

    6C 7A 20 ;

    6C 7B 20 ;

    6C 7C 20 ;

    6C 7D 20 ;

    6C 7E 01 ;

    6C 7F 1C ;

    6C 80 02 ;

    6C 81 03 ;

    6C 82 3D ;

    6C 83 71 ;

    6C 84 4D ;

    6C 85 82 ;

    6C 86 05 ;

    6C 87 04 ;

    6C 88 01 ;

    6C 89 10 ;

    6C 8A 11 ;

    6C 8B 14 ;

    6C 8C 13 ;

    6C 8D 1F ;

    6C 8E 06 ;

    6C 8F 15 ;

    6C 90 03 ;

    6C 91 12 ;

    6C 92 3E ;

    6C 93 0F ;

    6C 94 7F ;

    6C 95 07 ;

    6C 96 17 ;

    6C 97 1F ;

    6C 98 38 ;

    6C 99 1F ;

    6C 9A 07 ;

    6C 9B 30 ;

    6C 9C 2F ;

    6C 9D 07 ;

    6C 9E 72 ;

    6C 9F 3F ;

    6C A0 7F ;

    6C A1 72 ;

    6C A2 4F ;

    6C A3 7F ;

    6C A4 00 ;

    6C A5 57 ;

    6C A6 7F ;

    6C A7 00 ;

    6C A8 5F ;

    6C A9 7F ;

    6C AA 01 ;

    6C AB 37 ;

    6C AC 7F ;

    6C AD 72 ;

    6C AE 67 ;

    6C AF 7F ;

    6C B0 00 ;

    6C B1 83 ;

    6C B2 4F ;

    6C B3 00 ;

    6C B4 00 ;

    6C B5 67 ;

    6C B6 03 ;

    6C B7 0C ;

    6C B8 00 ;

    6C B9 10 ;

    6C BA 00 ;

    6C BB B8 ;

    6C BC 2D ;

    6C BD 01 ;

    6C BE 1D ;

    6C BF 00 ;

    6C C0 72 ;

    6C C1 51 ;

    6C C2 D0 ;

    6C C3 1E ;

    6C C4 20 ;

    6C C5 6E ;

    6C C6 28 ;

    6C C7 55 ;

    6C C8 00 ;

    6C C9 81 ;

    6C CA 49 ;

    6C CB 00 ;

    6C CC 00 ;

    6C CD 00 ;

    6C CE 1E ;

    6C CF D6 ;

    6C D0 09 ;

    6C D1 80 ;

    6C D2 A0 ;

    6C D3 20 ;

    6C D4 E0 ;

    6C D5 2D ;

    6C D6 10 ;

    6C D7 10 ;

    6C D8 60 ;

    6C D9 A2 ;

    6C DA 00 ;

    6C DB 81 ;

    6C DC 60 ;

    6C DD 00 ;

    6C DE 08 ;

    6C DF 08 ;

    6C E0 18 ;

    6C E1 8C ;

    6C E2 0A ;

    6C E3 D0 ;

    6C E4 90 ;

    6C E5 20 ;

    6C E6 40 ;

    6C E7 31 ;

    6C E8 20 ;

    6C E9 0C ;

    6C EA 40 ;

    6C EB 55 ;

    6C EC 00 ;

    6C ED 81 ;

    6C EE 60 ;

    6C EF 00 ;

    6C F0 00 ;

    6C F1 00 ;

    6C F2 18 ;

    6C F3 00 ;

    6C F4 00 ;

    6C F5 00 ;

    6C F6 00 ;

    6C F7 00 ;

    6C F8 00 ;

    6C F9 00 ;

    6C FA 00 ;

    6C FB 00 ;

    6C FC 00 ;

    6C FD 00 ;

    6C FE 00 ;

    6C FF 46 ;

    64 71 00 ; Set the Most Significant Bit of the SPA location to 0

    64 52 20 ; Set the SPA for port B

    64 53 00 ; Set the SPA for port B.

    64 70 B9 ; Set the Least Significant Byte of the SPA location

    64 74 03 ; Enable the Internal EDID for ports

    End

    Please refer (+) How can I use ADV7611 with an internal EDID - Q&A - Video - EngineerZone (analog.com)

    Thanks,

    Poornima

  • Hi,

    Thank you for your reply.

    I would like to ask a question regarding the answer to Q1 above.

    Is it correct that the Hot Plug Detect (HPD) transition always starts from H,

    HPD=H → HPD=L → HPD=H?

    Best regards.

Reply Children
  • Hi Tatsuya San,

             HPD=H → HPD=L → HPD=H ?

                Yes, the below suggested sequence is given by expert so it should be H -> L -> H

    1) HPA_MAN_VALUE_X =1

    2) HPA_A pin active =0

    3)  HPA_MAN_VALUE_A =0, sets HPA low

    4)  load up the EDID

    5) HPA_MAN_VALUE_A =1, sets HPA high, forces source to reload EDID

    Thanks,

    Poornima

  • Hi,

    Thank you for your reply.

    Sorry for asking so many questions.

    Before and after the HDMI device is connected,

    does the HPD sequence look like the following?

    ①Before connecting an HDMI device: HPD = L

    ②After connecting HDMI equipment: 

     1) HPD=H

        2) HPD = L

        3) 100ms wait

        4) HPD=H

        In this case, how long should HPD=H be maintained in 1)?

    Best regards.

  • Hi Tatsuya San,

          Please find the below comments,

     ① Before connecting an HDMI device: HPD = L

           Generally the Sink device will supply a voltage on an HPD pin to signal to the video source device that it is connected So the video source device monitors the voltage on the HPD pin and then initiates EDID requests as it senses incoming voltage.

         If HDMI device is disconnected then the HPD would be in LOW State (The absences of a voltage on the HPD pin indicates disconnection).

    ② After connecting HDMI equipment: 

         In this case, how long should HPD=H be maintained in 1) ?

          There is no specific time duration that we need to maintained for the case "1. HPD=H" .

         Please note But "After HPD become low, We need to wait 100ms".

    Thanks,

    Poornima