First of all, I rigged up two separate 3.3V power supplies (using a common 5V supply which uses a common 9V supply). I don't know if this is a good idea or not but it's what I decided to do. If anyone sees this as a debacle, let me know :)
Then after some experimenting, I finally got the DAC outputting something similar to the analog source.
Just a black screen:
And here it is with video playing:
The next step is to figure out how to stream this out to dual SD cards at 30 megabytes per second! :)
Hey Matt, this is MAME developer MooglyGuy, who did the HLSL shader system in MAME. Would you be willing to share a few seconds' worth of ADC output with me? I've been curious about writing a set of shaders that will decode an NTSC signal from a raw signal capture, but the raw signal capture has been a *bit* hard to find, to say the least!
ReplyDeleteHi MooglyGuy,
ReplyDeleteWhat a coincidence. I've been wanting to learn more about making an LCD screen look like an old CRT recently so it looks like we can help each other :)
Send me an email at http://emailme.ownby.org and let's talk over email.