Hi Paul,
I have finally gotten the encoder test pattern generator to work. It required me to write to registers 0xe48c-0xe48f the values for NTSC even though the registers default to these values. Now that I've gotten that part to work, I wanted to feed my own input image (color bars) through the part. I am trying to input a 1920x1080p60hz signal into the ADV8005. I am using the TTL parallel input. The chain looks like this:
TTL parallel input (1080p) => PVSP (480p) => PtoI (480i) => Encoder
I have the ADV8005 evaluation board and have been able to get the following chain working using that:
Rx input (1080p) => PVSP (480p) => PtoI (480i) => HDMI Tx
When working with the encoder on my own designed board I am using the same scripts I used for the HDMI Tx and eval board but made some changes. I switched the input from Rx input to TTL parallel input and switched the output of the PtoI to the encoder instead of the HDMI Tx. My scripts have not worked and all I get at the output is a gray screen.
I tried a simplified approach and use a 720x480p input to the TTL parallel input and send it directly to the PtoI to bypass the PVSP. With this setup, I'm seeing the input image (color bars) at the encoder output but the image at the output is gray scaled and shifted down and to the right. At the DAC output I can see the color subcarrier is there at the correct frequency and look very similar to the encoder test pattern. Do you have any ideas as to what is causing this? When I enable the color bar test pattern as a sanity check, I see that it is working but my input signal is not.
Thank you.