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ADV7842 questions

Question asked by ynakata Employee on Jul 24, 2013
Latest reply on Jul 29, 2013 by ynakata

Desinging with ADV7842.

Need to support the following signals.

     Input:          DVI-D,HDMI,Composite,S-VIDEO

     Output:       YCrCb 4:2:2, 8bit  


(1)  User needs to connect HD video signal to Y[7:0]=P[23:16] & C[7:0]=P[11:4], SD video signal to YCrCb[7:0]=P[23:16]

      Is it correct?


(2) When user needs to support both of DVI-D and HDMI, are there any rules/suggestions, which signal must be connected to which part, A or B?

     Can they connect HDMI to A and DVD-D to B port?


(3) To which port should Composite video,S-Y and S-C video signal be input?

      In the case of ADV7441, the user has used AIN11 for Composite, AIN10 for S-Y, and AIN12 for S-C.

     And if some AIN ports aren't used, can they be OPEN?


(4) Even if user doesn's 3D YC for decode of SD video, should user use external SDRAM?

      If need not to use SDRAM in the case, how should user design the circuit around all pins related to SDRAM?


(5) If user doesn't use D-terminal and SCART, how should user design the circuit of TRI1-8 and AVLINK?


(6) For I2C communication with ADV7842, SCL/SDA pin can be used.

     For DVI-D and HDMI, DDCA/DDCB_SCL/SDA pin can be used.

     In the case, user doesn't need to use TTX_SCL/SDA and VGA_SCL/SDA pins.

    Is it correct?


     If so, can those pins be open?


(7) Can we use the device without using REFP/REFN?

      If not, tell the reason why we need to use those pins, please.


(8) When user internal RAM for EDID, is it possible to do connection control by having HPD externally?

     If yes, can EP_ports be open?


(9) How to use ports of CEC, RXA/B_5V and HPA_A/B

      Does ADI have any examples of use, application note etc?


(10) For HDMI Audio, when user access it with I2S left justified, are the followings correct?


       SCLK=bit clock(64Fs)



          AP1=data ch1/2

          AP2=data ch3/4

          AP3=data ch5/6

          AP4=data ch7/8



Please let me confirm the above points.

Thank you in advance.