Products In This Thread

ADV7480 Production
The ADV7480 is a combined HDMI®/MHL® receiver targeted at connectivity enabled head units requiring a wired, uncompressed digital audio/video link from...
Datasheet
ADV7480 on Analog.com

  • State Suggested Answer
  • Replies 1 reply
  • Answers 1 answer
  • Subscribers 80 subscribers
  • Views 493 views
  • Users 0 members are here
Options
Related 

        

            Post
             Go back to editing
        

    

    


    

    









		












	
	
			
	
			
		
	
	
		

		
[ADV7480] About audio output from a laptop



		

			

									
					    tatsuya_sato
					
							

			
				
									
											
			
			
				
    
			
			
			    	
			                    
                
				                on Nov 28, 2022 
				
			
			
		
    

				
		
    
		    		    
		    
		    		            		        
    Category: Software
    
    		        		        		    		    	
			
    Hi,
    

     I have received support in this thread before, but I am still having trouble solving it,
    

    so could you help me?
    

     [ADV7480] About laptop audio output 
    

    After setting the EDID, the PC is plugged into the part (chipset),
    

    but the PC recognizes the Display but not the Audio.
    

    Although the ADV7480 side is ready to receive audio, the audio is not output from the PC.
    

    Is there any mistake in the setting flow after setting the EDID?
    

    I would appreciate it if you could check the attached Excel file from line 272 onwards.
    

    XLSX
    

    Best regards.
    
									
			        
		
    

				
				
		
    
			
						
									
									
						
						
			
			
			
			
		
    

        
        

					
    
			
    


    


	















    
	
    
	
    
					



			


				
	









	
      
	

    • 
	
      



	
			
		
	



      
	
      
		
      
							
					
      
		
      
			
													0
							
			
				
									
							        
			
			
			
      •  Analog Employees  
      •  Super User  
      
            
			                            
                        
                on Nov 29, 2022 11:43 AM
            
            
					
      
	
      

		
		
      
					
      Hi Tatsuya San,
      

              Please let us know, whether the reported behavior is observed in other sources like Player's and also check whether you can observe any frequencies from LRCLK, MCLK & SCLK of  ADV7480 Audio Port.
      

              Also note that " ADV748x cannot output audio over the CSI-2 bus. It can only output video over the CSI-2 bus. The only way to output audio is over the I2S output interface".
      

      Kindly note some of your register settings are different from the reference one. Please refer below,.
      

      For example.
      

        We found below additional settings which were not found in our reference script
      

      44 BF 12
      44 C0 00
      44 C1 00
      44 C2 00
      

      Also some values are differ from our reference script: For example
      

      Customer script:         Reference script:
        68 6C 0B                 68 6C 01;     HPA Manual Enable
      

        68 0F 1F                  68 0F 00 ;    Audio Mute Speed Set to Fastest (Smallest Step Size)
      

      Below register are present in reference script but this has been omitted in customer script
      

        68 83 00 ; Enable All Terminations
      

      Also some registers are added without values
      

      E0  71
      E0  40*
      68  F8
      68  01*
      E0  71
      E0   40*
      68  F8
      68  01*
      

      Please note that 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.
      

      

      Thanks,
      

      Poornima
      
			
      

		
			
	      

		
		
	
      
	
      
		
      
			
		
      
	
      
	
      
		
						
						
						
						
				
				
		
		
      
			
		
      
	
      

      

      •