Arduino Due and AD725 How-to?

I think you are flogging a dead horse here - the Arduino is nothing like powerful enough to generate video and run a gui - there's a thread here on this topic and the consensus is VERY discouraging.

Color SVideo. Like the AD725 chip except in software? - Arduino Forum

If you want video and a gui you need to start off with a more powerful processor - or offload the task - FTDI make a nice video controller chip which you could use with an Arduino - and they also sell kits with an LCD display included. The FTDI chip is an LCD controller - it doesn't do composite video.

If you explained what you are trying to achieve overall it might be possible to be more helpful.

MK

The Due runs at 84Mhz, which is much faster than the overclocked ATMega used in uzebox, so clearly it is quite possible to achieve.

I have a device that outputs svideo and composite. I will switch the video signals to the GUI and configure the device with it before switching back. An LCD is not an option, it must be both svideo and composite. I was thinking I could just use bitmaps and basically make a photo viewer that uses provided file names.

I don't mind offloading if I can find a device that offers what I need. I even looked into using an actual photo viewer that outputs the signals I need, but none of them allowed me to provide the file name. They are all simple next-previous type.

I chose the AD725 since it is already being successfully used with an Atmel (uzebox).

The Due runs at 84Mhz, which is much faster than the overclocked ATMega used in uzebox, so clearly it is quite possible to achieve.

I have a device that outputs svideo and composite. I will switch the video signals to the GUI and configure the device with it before switching back. An LCD is not an option, it must be both svideo and composite. I was thinking I could just use bitmaps and basically make a photo viewer that uses provided file names.

I don't mind offloading if I can find a device that offers what I need. I even looked into using an actual photo viewer that outputs the signals I need, but none of them allowed me to provide the file name. They are all simple next-previous type.

I chose the AD725 since it is already being successfully used with an Atmel (uzebox).

It may be a lot harder than you think - this kind of precisely timed coding gets more difficult with a complex processor. I haven't looked at the ARM processor in the Due in enough detail to say that it's impossible to replicate the Uzebox but you do need to check the rate at which pins can be toggled.

However, when you said you wanted a GUI I thought you meant somewhat better video than the Uzebox manages.

I don't think I quite understand yet exactly what you are trying to do - is the plan that the Arduino just provides a GUI and the photo bit maps are done by something else or is the Arduino to do it all ? What resolution and number of colours are you looking for.

MK

Thanks, Michael.

The GUI does not at all need to be fancy. I'm not even expecting motion at this point. I didn't want to go with the TVout lib because I desire color and it doesn't provide svideo. The resolution doesn't even need to be great, but if my math is correct, the Due could easily reach full SD resolution - 480i - with 256 colors. This resolution is a little over half of what the Due should be able to provide, which came to a resolution of roughly 800 pixels wide. So, assuming all of this, I assume the toggle speed should be fine. I don't have an oscilloscope to be sure.

The plan is to use the Due to read a bitmap from an sd card and then generate the proper signals used by the AD725. I don't know anything about how to even get started with providing the proper signals using the Due.