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adv7390: yuv input - possible or not?

Question asked by aha on Apr 9, 2013
Latest reply on Apr 10, 2013 by GuenterL

hi guys

 

I am trying to connect an omnivision ov7740 vga sensor to the adv7390, to make a composite SD PAL video signal.

It is wired up with 8-bit interfacing, using external HSYNC and VSYNC and a 27MHz clock.

I got as far as to generating a stable, composite signal that syncs OK. Unfortunately the colors are *WAY* off.

I can clearly recognize the picture, but I get a massive pink/blue tint to the picture, and no green output.

 

Checking the datasheets I realize that the OV7740 outputs YUV color, and the ADV7390 wants YPrPb.

I had previously assumed they were the same/close enough, but I now begin to suspect I may have been mistaken.

Looking thru the internet I find suggestions to suggest either.

 

So, my question is simply: SHOULD yuv color be possible to use with the ADV7390/91 or not?

 

Also, looking thru engineerzone I can see that somebody attempted to interface the omnivision YUV-colorspace sensors

previously, but I didnt see a clear result in that thread.

 

As I had not managed to route the clocks thru the EVM, I have wired the clock & pixel path external to the evm (I am

just using the evm for I2c control and Power), so it is certainly possible that is mixed up somehow. Knowing if I should

expect this to work or not would certainly speed up my debugging!

 

br

aha

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