[ADV7480] About laptop audio output

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