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VGA Generation Issue

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nickbild:
I've got an issue with a VGA generator that I built, and I wanted to see if the particular problem I have jumped out at anyone as having an obvious cause.  See the attached image of the 640x480 @60Hz display.

The first 8 lines are pushed about 7-8 pixels to the left off screen, which leaves a block box on the right hand side of these lines.  The remaining lines (9+) are pushed about 7-8 pixels to the right off screen, leaving a block box on the left hand side of these lines.

The signal I'm generating looks correct with my logic analyzer (specs: http://tinyvga.com/vga-timing/640x480@60Hz).  I can't figure out what is causing this.  Any ideas?

PS - The screen should be white, with a single red row at the top, and another red row at the bottom.

Thanks in advance!

Benta:
Well, obviously your own generated signal isn't correct.
But with the sparseness of information that you provide, nothing more can be said.

nickbild:
What information would be helpful?

Benta:

--- Quote from: nickbild on December 04, 2021, 09:06:13 pm ---What information would be helpful?

--- End quote ---

Hmmm... let me see.
Until now, you've provided a screenshot and a link to the VGA specification.
Do these help us solve your question?

Not really. Our crystal balls are out of order.

How about signal traces of your video output? Just to begin with. And try understanding how other people receive your question. It's called empathy.

tooki:

--- Quote from: Benta on December 04, 2021, 10:02:24 pm ---
--- Quote from: nickbild on December 04, 2021, 09:06:13 pm ---What information would be helpful?

--- End quote ---

Hmmm... let me see.
Until now, you've provided a screenshot and a link to the VGA specification.
Do these help us solve your question?

Not really. Our crystal balls are out of order.

How about signal traces of your video output? Just to begin with. And try understanding how other people receive your question. It's called empathy.

--- End quote ---
That’s not what empathy means. (Empathy means the ability to understand and share another person’s emotions.)

And while the content of your criticism is factually correct, it’s rather devoid of… empathy. (Specifically, by taking an unduly harsh tone.)

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