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Correct, analog pins 4,5 are not used, and digital pins 11,12,13 are not used. Digital pin 10 is connected to the button.
However the pins are not broken out to pads, so you’d have to solder directly to the ATmega328 chip’s pads to use these pins. I should have broken out these pins to pads 🙁
Yeah, actually you can’t use the Arduino serial library with TVout (or any other library that uses interrupts). The TVout library comes with a polling version of serial communication “pollserial” that does not use interrupts, so you CAN use that while using TVout. See the TVout examples of pollserial.
I must say that I cannot explain why a bypass cap across 8 and 9 would clear up the jitter. I will keep thinking…
Hmm. It’s hard to image what would cause this problem with the unmodified simple overlay demo sketch. I have had no reports of this problem before. It really does seem like you’re using interrupts or using too much memory, but in an unmodified sketch this would not be the case.
Have you adjusted the small 100K pot with a screwdriver? This can help tune the timing a bit.
Only composite video input and output is allowed. An Android phone is not going to output composite video without some special hardware. Many small camera modules can be used, though. There are small cameras at places like Sparkfun that have composite video ouput.
I was able to find the closed captioning on all devices by trying different values. According to the closed captioning specification, it should be on line 21. But I found it on lines like 13 or 14. Just try different values and you can see the data if you display it on a lower line. The project code explains this. You can just experiment.
Refer to Adafruit’s site for information on how to drive the 32×32 panel. You need to do lots of extra wiring. My product is not designed for the 32×32 panel, it’s designed specifically for the 32×16 panel.
Sorry, I don’t have any guidance for a satellite receiver. I just don’t have one. I don’t even know if the closed caption data is coming over that kind of a video feed using the standards that I used.
Just try different lines. Try everything from 1 to 30 if you have to. Once you find the line that the data is on, then you can adjust dataCaptureStart value to line up the bits with the capturing. Please refer to the TVout source code I provided to understand how it works.
That’s very interesting — I have not experienced that. There must be some kind of strange timing problem, but I’m glad you have a working solution. Good job finding that workaround.
I’ll keep thinking about this one….!
You just need to keep trying different values for the line and the dataCaptureStart values.
I think you are asking for a video instead of pictures, but I don’t have one now. Capturing the closed caption info is a very tricky project, so you need to keep trying hard.
It would be much easier to use serial communication between the Arduinos. TVout comes with a polling version of serial communication (versus interrupt driven). See the “pollserial” library in TVout. There are examples in the “examples” folder.
This allows you to perform serial communication between the devices even if one is using TVout. Connect RX to TX and TX to RX between the Arduinos. Also connect the grounds. Use pollserial on the Arduino using TVout, and use the normal Serial library on the other Arduino. I’d use a speed of 9600.
Hope that makes sense. This will allow you to communicate in the easiest manner. I would avoid I2C unless you can find a polling version. My trimmed down I2C implementation is only suitable for very tiny amounts of data (like nunchuck readings).
The video processing code (TVOut library) is interrupt driven and depends on very precise timing. Trying to use other interrupt driven protocols will interfere with the Video Experimenter. Basically, it takes all the muscle that the ATmega328 has to generate video with correct timing.
I successfully used I2C communication with a very trimmed down version of the I2C library when I implemented the Wii nunchuck controller for my Hackvision product. The important part is only doing I2C communication during the vertical blanking interval in the video. That is, the only time you have time to communicate is at the end of each frame.
See the Hackvision Controllers library (specifically the nunchuck controller) and i2c.c, i2c.h for some info on how to do this. It’s tricky.
The Controllers library can be downloaded from:
http://nootropicdesign.com/hackvision/games.html
