PConst,
It was difficult to help you with out knowing what you have. Every week some one says "HELP, HELP, my thing is not working" Then it takes 25 posts to find out what "thing" is.
One of the reasons for the forum is for all of us to learn. We helped you and, hopefully other people can read this and learn how to get from TTL to video. Other people deserve to learn.
We all took time to help you, with out knowing what the problem was.
In return we hope you will say what made it work. Explain some thing, anything. Help the next person.
If you said, "it is a secret, I don't want you to know because I will make 1,000,000 of money on this." The I would have thought "what a ass, he gets free help and makes big money. but ok"
You said "It is in my head". I do not know what that means.
Many of the last posts are "People are so stupid". There are many smart people on electronics forums that help and learn for free. 99.9% of the people are happy. If every one in your world is stupid and angry and out to hurt you, then this is your problem, "in your head".
On the good side; Thank you for the picture of the working TV. That is the only "thanks" I need.
Hi Ron. I can explain what made it work. I built the circuit "from my head" without schematics just to get a feel for it. I had the idea about how to do it by using counters and logic to select which lines are horizontal sync and which lines are vertical sync. I did this without schematics so I have no schematics to offer. When I do have them because I will remake the circuit now that it works, then I will post them. So my signals were all sync signals, and what I wanted to do, and what created the issue was that I wanted the screen to go completely black after the sync signals. I wanted to do this simply to be able to see that the TV was indeed synchonizing to my signals. I wanted a way to make it black by tinkering it, and then making it white again, to see whether the TV would respond. If that worked, then I could be sure it was all working.
But my TV would display white no matter what voltage levels I would send to it after the sync, because the voltage I was sending was constant between each synch. So whether the voltage was zero or 1V or 4.5V wouldn't matter. It was always white! This drove me nuts because all materials on the web told me that if I varied the voltage between 0.3V and 1V, the shade would change. They also said that the reference voltage was black after synch. So by logic my tv should be black to start with. It was always white.
After I attached a cap to the output, my output was differentiated, with spikes after and before each synch. What was the output on the TV ??? It was a peak of white on the left, and then it went black on the right. That was the big clue. It must have been that the TV was taking the first voltage after synch as white rather than black, and because all my voltages were constant after synch, the tv would always be white.
So I made a counter to change the voltage after the synch multiple times, and indeed the TV started to show different shades. It had worked.
The solution was simple, the problem was that I didn't want to change the voltages until I could see the tv going black, and that was the problem because it simply wouldn't!
It was only after your post that I finally decided to try and change the voltages. So it's all thanks to you. Now the next step will be to make an interface so that this can comunicate with my second project, an 8bit computer also using 74HC IC's. Which is almost ready in fact!
**broken link removed**