strange display

[navic]

Just built my VE board and uploaded the overlay demo which didn’t seem to work. I noticed that there are small white specs moving on the screen while the sketch is running, this must be the overlay because when I upload a sketch with just a delay statement, those little white specs are not present.

I then uploaded the DemoNTSC example from the modified tvout library and can at least make out the shapes, but they again move very rapidly across the screen, the text is unreadable. I don’t know anything about video but assumed it had to do with my monitor so I sent the output to a pair of video goggles but the same fast side to side, up and down motion of the overlay persists.

I did try to slowly tweak both pots on the VE board with no luck at all. I lowered the height and width in the overlay demo and still no change. What could cause this?

Thanks for the help!

[Michael]

What country are you in? That is, do you have a PAL television? If so, the TVout library needs to be initialized with PAL instead of NTSC.

So, the most basic test would be to set the sync select jumper to the D9 position, and the output select switch to the “sync only” position. Turn the R4 pot (small one) to the lowest (counterclockwise) setting. Then load the DemoNTSC (or DemoPAL if you are not in North America) and run it.

You aren’t using an Arduino Mega are you? VE is not compatible with Arduino Mega.

Assembly things to check:
– ensure you installed the diodes with the correct polarity (direction)
– ensure the LM1881 chip is oriented correctly

I’m happy to look at any photographs or videos you may be able to provide.

[navic]

I’m in USA with an NTSC TV, Arduino Duemilanove and checked the assembly again. Got the DemoNTSC working now, I didn’t know I needed to jumper to D9 for that sketch.

What positions do I need to put the switch and jumper for the Overlay Demo to work? I’ve been using Sync Select and Overlay.

A picture is attached, my phone camera isn’t the best but you can see one of the lines toward the top of the image.

Thanks for the help, I’m really excited to get this working!

[Michael]

The jumper and switch settings are documented on the product page:
http://nootropicdesign.com/ve/

For overlay, the SYNC SELECT jumper should be set to V INPUT
and the OUTPUT SELECT switch should be set to OVERLAY.

Seems like a synchronization issue. What are you using as a video input source? A video camera?

[navic]

Yes a video camera that I found from an unlabeled toy in a thrift store. The only identification on the camera is the RD-1049(sensor) ver:A on the top. I couldn’t find any data on google for this. Could the camera display fine when plugged into the tv but have synchronization problems with the ve shield? I don’t have any other input source at all, no vcr or even television signals.

If you think it’s the camera problem do you have any suggestions or links for inexpensive cameras? Thanks again.

[Michael]

It is possible that the TV is more tolerant to poor synchronization than the LM1881 chip. I got a VCR for $10 from someone on craigslist — that might be a cheap way to get a video source. Or borrow a video camera from someone?

Maybe the camera is outputing PAL. Try changing NTSC to PAL in the OverlayDemo sketch.

And make sure you are running the OverlayDemo otherwise unmodified. Don’t change anything else.

[navic]

PAL overlay demo does the same thing, gotta be the camera right? I will find a VCR and tape. Will get back to you when that is accomplished.

[navic]

Well no luck still. Tried a different tv also. Here is a link to the video, sorry its sideways but you can see whats going on.
http://www.youtube.com/watch?v=psUmHNi76F8

[Michael]

What was the input source in this (sideways) video? A VCR?

This is your setup, right:

VCR -> VE Input
VE Output -> TV

R4 is in lowest position? (counter clockwise). Maybe you can send me a clear picture of your VE from the top and bottom.

And your OverlayDemo sketch is completely unmodified? Just to be sure, maybe grab the source from my site again?

[navic]

The setup is correct, vcr->ve input, ve output->tv. R4 is counterclockwise and I tried a fresh download of the sketch.

[Michael]

Ok, your board looks fine. At this point, I’m not sure why your LM1881 chip is not working. Maybe it’s defective or damaged. I can only suggest removing it and reinserting it.

I’ll do some experiments tonight and if I don’t figure out anything, I’ll arrange to send you a replacement Video Experimenter (assembled/tested). I’ll contact you via email.

[Michael]

Also, you could try the Video Frame Capture project here:
http://nootropicdesign.com/projectlab/2011/03/20/video-frame-capture/

[navic]

I did reseat the chip. Will try videocapture tonight

[navic]

Video capture frame doesn’t work either. When starting with sync select in video input, output select in overlay and pot all the way counterclockwise there are several lines across the screen. Switching output select to sync only kills all video.

[Author]

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