Scrolling overlay with NTSC/Uno

Store Forums Video Experimenter Bugs/Problems Scrolling overlay with NTSC/Uno

Viewing 7 posts - 1 through 7 (of 7 total)
  • Author
  • #384

    I’m tantalizingly close to getting my self-built Video Experimenter shield up and running. (Aside for inbound Googlers: the Diecimila does not seem to work with this kis despite conjectures that it will, so get an Uno).

    My problem is that the overlay is scrolling even while the video is not. Here’s a video:

    Here’s a picture of my kit, which should be according to spec, but who knows:

    I’ve tested this with two input sources and two displays — same issue occurs across all so I’m looking into possible board issues at this point.

    I’ve seen some people had RF interference (viewtopic.php?f=26&t=2588) but I wouldn’t know how to debug that. I checked my soldering and no pins were missed and nothing stands out.

    , ever seen this before and, if not, do you have any ideas how best to go forward with debugging?


    The YouTube video is private, so I can’t see it.

    I have not run into this scrolling problem before. It seems to indicate something is wrong with the vertical sync timing. I’ll have a look at the video when you make it public….

    Also, the VE will not work with the Decimilia because it doesn’t have enough memory.



    Thanks for taking the time to reply. I apologize about the privacy settings, I’ve since changed them.

    I was thinking it was some sort of sync issue, which from other threads suggests that maybe I got a resister wrong or something. Thank you for taking a look when you can.

    Toward the end of the video, you can see where I put the board from Overlay into Sync mode. It appears to be vertically synced for a second and then goes a little haywire.


    I don’t see anything wrong with your assembly. The same problem occurs regardless of input source and regardless of display? That tells me there’s something wrong with the device. I’ve never seen this before.

    Are you in the US? If so, it’s easy to send in the device to me and I can take a look. Repair/replace, or whatever.

    I’m sure you’ve double checked for solder bridges, etc.


    I’m in New York. I’ve got a replacement board on the way (this time assembled and tested, thank you!). In the meantime, I’ll check the solder points again on this bad boy.


    New, pre-assembled board came in. Testing, I see the exact same issue with sync mode (only when using D9 power) and the scrolling happens in both sync and overlay.

    I purchased the Uno fresh for this board, but two boards in a row can’t be coincidence. I wonder: might it be at the software level? My first guess was display so I’ll try that again.


    What do you mean by “using D9 power”???

    The sync select jumper should be in the “v input” position if you are trying to use the Video Experimenter with a video source.

    With sync select jumper on “v input” does the strange scrolling happen?

    If you have the sync select set to D9, then you should not expect things to work when using a video source. The D9 position is only to be used when generating video from the Arduino and there is no video input source to get the sync from.

    The settings are described in detail on the product page:

Viewing 7 posts - 1 through 7 (of 7 total)
  • You must be logged in to reply to this topic.