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mads
- 16th October 2003, 17:55
Hello all... new in here.. hello's go around..

I want to play with my TV and PIC basic..... have any one done this before... a quick search onthe giant net gave me nothing to go from (im nothing with PicBasic and im not going into ASM)...

so please if anyone have a few trick/tips or a full code on how to make a single pixel on a TV screen (pal) then it would be of the greatest help to me and i guress to who else want to plwith this stuff.....

I short, what i have in min....
I want to make a device which will be plugged into the tv's scart and play a small game or animation of some sort,,, just for fun.. i know some people made a pong with the pic16F84... but that was all done in ASM..(uhh and i really should be in 16F628A or better 877A since they are the best chips :)

thanks. let the discussion rool...
/// Mads

Melanie
- 17th October 2003, 11:35
This is where I ask if you have any experience with TV's other than watching them?

If the answer is No, then as a start go here (there's plenty of other places on the net too)...

http://www.epanorama.net/links/videosignal.html

and read up about what makes up a composite video signal, horizontal and vertical syncs, differences between monochome video and colour video, interlacing etc. There's no point in trying to generate a TV signal if you don't know what you're doing to start with.

johnramsbottom
- 14th November 2003, 11:43
Yes I agree with Melanie. Even a standard TV signal is a very specialised thing. Essentially analogue in nature and very fast with a solid time structure! I was associated with electronic image generation in the pre PIC days. Although it was done using relatively simple logic chips, this type of circuitry could often 'think' about several processes at once and extremely fast. A PIC cannot. It is possible to do what you are hoping with a PIC but speed is important as well as the the fact that you are forced into synchronising the program processing in the PIC with the TV signal scanning speeds. Using a certain amout of extra hardware may make things easier for the PIC.
I will send a longer message when I've got a bit more time but I would strongly advise doing a bit of reading up on TV signals. Don't worry too much about how colour information is portrayed for now. The most important part of a TV signal is actually a hign definition black and white with infinite number of levels (being analogue). Sync pulses are included to synchronise the TV to the signal.

John R