Wiring Diagram: OV7670 to Arduino Due

Hello! I'm trying to interface between the OV7670 camera and Arduino Due. I've tried several times and cannot recognize the device on the I2C scanner.

There is only one diagram I found floating around (see attachment). This diagram is missing the HREF pin. At first, I thought it must be correct, but now I think the HREF pin is required. See this link with the VGA description: Digital Camera Project (dejazzer.com). All the wiring diagrams for Arduino Uno show this HREF pin wired to the D8 pin on the Uno.

Does anyone have any thoughts on the matter? Or, better, can anyone confirm if the attached wiring diagram is correct or not?

I'm puzzled too.

HREF raises when a new row is to be sent, and goes low when the row is complete.
If you know the resolution you can presume the line endings knowing when the transmission of a new image starts.

In the sketch I found for the Due there is a RDY tag that could be interpreted as the start of transmission. But then I'm quite lost, because I can't find a working reader of the output, as the one linked by the Instructable I found is no more online. In the comments I found a sketch made in Processing, but there are some glithces... as it doesn't manage HREF and it doesn't know when the transmission starts, if I start the script after the Arduino then the image is not centered.

I tried to write another one in python but it has the same problem. [edit: I'm working on it]

Besides, every guide I found says that capturing an image in B/W is easy as you can just take every other byte for every pixel (the luma), while croma is shared for every other pixel.

After some trying, I managed to write a script that reads the output of the cam. HREF was not needed.

Maybe the I²C scanner doesn't detect the cam because XCLK is not receiving a valid clock signal. No clock, no I²C communication.

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