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i want the adv7612 output 16bit YCbCr with vsync ,hsync and de.

I sellect 16BIT SDR ITU-BT-656 Mode 0 with set the value  98,03, 80

the regs value setting :

98 ,00, 02,

98,01, 06,

98,02, F5,
98, 03, 80,
98, 04, 62,
98, 05, 29,
98, 06, A6,
98, 0B, 44,
98, 0C, 42,
98,14, 7F,
98,15, 80,
98,19, 83,
98,33, 40,

44,BA, 01,


68 9B 03 ; ADI recommended setting

68 00 08 ; Set HDMI Input Port A (BG_MEAS_PORT_SEL = 001b)

68 02 03 ; Enable Ports A & B in background mode

68 83 FC ; Enable clock terminators for port A & B

68 6F 0C ; ADI recommended setting

68 85 1F ; ADI recommended setting

68 87 70 ; ADI recommended setting

68 8D 04 ; LFG Port A

68 8E 1E ; HFG Port A

68 1A 8A ; unmute audio

68 57 DA ; ADI recommended setting

68 58 01 ; ADI recommended setting

68 75 10 ; DDC drive strength

68 90 04 ; LFG Port B

68 91 1E ; HFG Port B

when i change the Resolution to 1920*1080, there display,but a litter time ,it disapper,

is there any problem with regs setting .

  • FormerMember
    0 FormerMember

Setting 98 03 0x80 is correct.   just make sure you have the right pixel bus connections as shown in UG-216 Table 77.  The rest of the writes should follow script 6-1f.

If you are not using our eval board then you may have to tweak 98 19, LLC DLL phase adjust to work on your custom board.  The phase delay is board dependent.  You might also tweak 98 14, drive strength, some times you can over drive or under drive the pins causing strange effects, again this is board dependent.

Try testing you system with a non-HDCP source to make sure the HDCP isn't the problem.  When you say little time, what is little?
  • thanks for you reply.

    i am not using eval board.

    there are right pixel bus connect as show in UG-216 Table 77 on my custom board, i set the LLC DLL phase like this 98,14,7F;98,19,83;

    i using the Tektronix to measure the LLC and Hsync ,Vsync.they are all correct,

    the test source come from the PC's displayport

    when i change the resolution of the source ,it can display a picture,but if i don't change the resolution ,there is no response.

  • FormerMember
    0 FormerMember

    One possible cause of this problem is the phase relationship between the output pixel clock and the pixel data.  LLC_DLL_PHASE=0x83 was set for our evaluation board.  It is board dependent.  I suggest testing each of the 16 possible PHASE adjustments to find one that works.  This only has to be done once and then this new phase adjustment should work for all other boards of the same design.  This problem is most prevalent at the highest resolutions such as 1080p where the clock rate is highest.  By the way, this type of test data is called a "Schmoo plot".

    You may be able to measure the correct frequencies on VCLK and the sync lines but sink may  be having problems latching on to them correctly.  Again try each phase setting to verify.

    Have you tried a DVI source to make sure this is not HDCP related?

    Another possible cause is the input layout is not correct causing problems at the higher frequencies.