If missing and like this ----- ---- it should be easy to trigger on where the frame should be.
You guys drove me nuts, saying i could find something i could not "see", but now i understand why. Problem is, you did not know, how that stream of frames (is my terminology right here?) really looks like. It is not a konstant frames every x us. So i could not use any "time and level" trigger.
As my problem seems to have dissappeared, id say, we can focus now on other topics/things, but if anyone has another good idea, your´re welcome. Using a board to trigger the scope was the best so far for me.