ADV7180 about "LL NSTD" and "CMG[11:0]"

Question

Hi, 
 My customer is considering the ADV7180. 
 ① Regarding LL NSTD (Addr:0x12,Bit[4]) I think that 1 is set for non-standard line lengths, but please tell me the specific conditions (e.g. no VSYNC, etc.) (What is "non-standard" for 1 to be set?) 
 ② Regarding CMG[11:0] (Addr:0x2d,Bit[3:0]-Addr0x2e,Bit[7:0]) Please tell me the specific conditions for 0xfff. 
 
 Best Regards, 
 Naohisa

PoornimaSubramani · Accepted Answer

Hi, 
 1) 'LL_NSTD' bit in register 0x12 indicates whether the line length is nonstandard. If this bit is set, it suggests that the line length of the incoming video signal is not following standard values, which can cause timing issues and possibly flickering if the decoder is not handling it correctly. 
 This occurs when the number of pixels per line deviates from the expected values defined by the broadcast standards (e.g., NTSC, PAL). 
 
 Note: All the writes given in the scripts are required for the correct operation of the ADV7180. Make sure XTAL input pin of ADV7180 is connected to the clock source 28.636MHz 
 
 2) Below table shows when CMG[11:0] becomes 0xFFF (4095). The specific conditions for 0xFFF is when color burst amplitude is minimum then you need maximum Chroma Magnitude.

Thanks, 
 Poornima)

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ADV7180 about "LL NSTD" and "CMG[11:0]"