In parallel with our "VSYNC output issue" thread, I would like to ask Analog Devices to give information about the Manual EQ settings.
Since our ADV7619 is receiving the TMDS singnals not via a HDMI cable but from PCB tracks, the Auto EQ function does not work properly. We already tried all the tips and tricks in this forum how to restart the Auto EQ without any success. The only fruitful action was to switch the EQ to Manual mode and adjust the "EQ Gain" register according to the following hint from thread "ADV7619 failing HDMI compliance test 8-7ADV7619 failing HDMI compliance test 8-7 (TMDS jitter tolerance)" by PaulS:
68 91 [6:4] = 000 => if using port A, 001 if using Port B.
68 85 11 = > Puts the equalizer in to manual mode which is necessary for <27MHz.
68 93 03 => uses a manual EQ gain
68 5A 80 => this updates the EQ settings above.
By changing the "68 93" EQ Gain register, we could achieve significant change in behavior of the ADC7619 with regards to VSYNC stability. We are looking for the meaning of the bits of this register, and the other EQ related registers. Our goal is to increase the stability.