Go Down

Topic: Arduino Ethernet and TVOut? (Read 2581 times) previous topic - next topic

uberhund

May 14, 2012, 03:59 pm Last Edit: May 14, 2012, 04:04 pm by uberhund Reason: 1
I've successfully implemented the DemoNTSC sketch using later versions of the TVOut libraries on an Arduino Uno.

However, the same sketch and circuitry does not display video when uploaded to an Arduino Ethernet board, regardless which version of the TVOut library I use. I can detect some sort of signal from the Arduino Ethernet, but the analog TV I'm using is not able to render it into video.

Does anyone know what changes might be required to implement any version of TVOut libraries to work with an Arduino Ethernet board?
Santanyana was only half right. We are doomed to repeat history with impunity, whether we choose to remember it or not

RandallR

I don't know if this is the problem because I have not looked at the Ethernet libraries.  But the TVOut libraries take over Timer1 and possibly Timer 2.  This can play hell with PWM, Tone and other things.  It may be that your Ethernet is one of those things.

uberhund

Thanks for the observation, RandallR. I've been looking at conflicts and notice potential others as well (e.g., pin 11 on the Arduino Ethernet card may be in use by both the ethernet and TVOut libraries).

I've been trying to avoid it, but it looks like I will have to implement ethernet on a separate Arduino from the TV driver, and communicate between the two using I2C, which doubles the cost and complexity of the project.

Either that, or wait a year to get my hands on a Raspberry Pi.
Santanyana was only half right. We are doomed to repeat history with impunity, whether we choose to remember it or not

RandallR

If you can program, you might want to look at the libraries and see if you can resolve the conflict.  For example, TVOut uses Timer 2 for audio generation.  If that is the conflict and you don't need audio, then disable that part of the TVOut library.  You can download the Datasheet for the processor from ATMEL.  This gives a very good description of the various timers. 
I was thinking of writing my own version of TVOut to use only timer 2 and use less memory.  However, it has not been a priority.

pablogs9

Hey! I had the same troubble, so I started reading the TVout library and in the main .cpp there are some audio functions (someone sais that both libraries Eth and TVout use the pin 11) interfering with the Eth lib, so I deleted them. Now, the TVout works great at the same time that Eth, but the sound is unavailable.

I upload the .zip with the modified lib

Graeme

Hi there!

I'm in a very similar situation - but I have an Arduino Uno with an Ethernet shield added. What I want to do is display text from the web using the tvout library. I've found that it will not work with the Arduino ethernet.h library included... nothing gets displayed. If I remove it, it will display text.

I have tried compiling using the ethtvout library included in the previous post (thanks!) but it had the same result.

Is there anything else I could try or should be looking at?

hsantini

Hi There!

I have exactly the same situation as Graeme - but I have an Arduino Ethernet Board. What I want to do is display text from the web using the tvout library. I've found that it will not work with the Arduino ethernet.h library included nor the Serial... nothing gets displayed. If I remove it, it will display text.

I have tried compiling using the TVoutEther library included in the post from pablogs9 (thanks!) but it had the same result. Has anybody found a workaround?

Thanks,
Hector

Is there anything else I could try or should be looking at?

mcnobby

I'm interested in this too, I wrote my own PAL driver for UNO/Nano and I had trouble implementing other libraries in there, in the end I hacked my own things to work, I think I also didnt use any of the sound functions to avoid conflicts. There could also an interrupt issue as I think the Ethernet uses a timer somewhere

It is possible to do an awful lot of things simultaneously with video, I wrote some code to drive a VGA monitor (over twice as fast as PAL) in 17-bit colour while reading serial data at 250kbps from the UART, so I am sure a bit of Ethernet SPI should be possible

https://youtu.be/IlkEMJtieXM

Bob
Please subscribe to my YouTube Channel : https://www.youtube.com/user/Recovered
Electronic and Software Engineer for e-plex.co
DIY DMX Lighting Group : https://www.facebook.com/groups/584412254990472

Go Up
 


Please enter a valid email to subscribe

Confirm your email address

We need to confirm your email address.
To complete the subscription, please click the link in the email we just sent you.

Thank you for subscribing!

Arduino
via Egeo 16
Torino, 10131
Italy