Hi great comunity!
It’s been a few years since I started working on this Composite/VGA video synth which I plan to make open source. But I hit a blocking road.
SMALL VIDEO DEMO: https://youtube.com/shorts/ao-Zw99gN0Q
It has a layer system in which each layer has different patterns which draws different sprites
I think it looks promising, it’s made with a RP2040 for the cheap price.
It has USB Midi, an LCD screen all working perfectly.
It also uses a AD724 for NTSC/PAL composite output which requires INTERLACED VGA OUTPUT!
And here lies my problem
I was using Arduino/platformIO with this VGA library:
https://vanhunteradams.com/Pico/VGA/VGA.html
Which works great but it only has NON-INTERLACED VGA OUTPUT, so it doesn’t works with AD724.
So after a lot of work I could implement this library:
And got it working in tandem with the AD724! I could produce rectangles, shapes and such.
The only problem is that, with that new library, if the RP2040 is working hard, which is my case, it produces glitches in the image, which you can see in my video demo.
I’m now stuck, don’t know where to go. I’m not an expert in programming DMA, but with the help of chatgpt (I know, sorry jajaja) I tried to change Hunter Adam’s library to display interlaced output, got stuck. And also tried Hunter Adam’s library way of work with the pico-mposite library and couldn’t make it work.
There something about Hunter Adam’s library that doesn’t make it glitch even at extreme processing that pico-mposite doesn’t has.
Anyone could guide me in what to do or try?? Thanks a lot!! 