Digital to digital output?

[Numbski]

Reading over your description here:

https://lostnintendohistory.github.io/DS-TV-OUT.html

"The final, production-ready board contains a DAC (Digital to Analogue Converter) which turns the 10 bits digital signal at 16.7 MHz provided by the DS Lite into a proper analogue signal. This signal then goes through an operational amplifier and it’s ready to be delivered to your nearest TV trough composite video."

If I am reading this correctly, wouldn't it be possible to output this via DVI or DisplayPort? I may be misunderstanding, and that may require RGB encoded data for conversion, whereas this bitstream may just be the single CVBS - but somewhere in the back of my brain, I would swear either DVI or DisplayPort can handle that. I am going to go do some digging - but that would obviously require fiddling with the bitstream on the fly to make it work, but every little bit of help we can give the signal, the better.

[Numbski]

Coincidentally, TMDS (DVI, HDMI) can also be 10-bit. Who knows what your 10 bits are versus TMDS 10-bit, but that's a thing.

DVI Spec

[dogtopus]

Looks like it's possible, but it would probably be no different than a composite to DVI converter, minus the ADC. Honestly it sounds like too much work for subpar result (comparing to regular RGB to DVI/HDMI aka the expensive converter).

[Numbski]

Maybe, maybe not. I'm headed to bed, cuz it's late where I am, but the question is what we have in data coming across that ribbon cable. Again, if I'm reading it right, it says it is cvbs - but 10-bit encoded, which would make that a very unusual bitstream. That ribbon cable was assumedly supplying digital video to the top screen before, so I would assume somewhere in that tangle of data that rgb data is in there somewhere. Still a whole lot of assumptions on my part. I'd like to spend some time getting into the nuts and bolts of what is happening here. Otherwise I feel silly shooting from the hip.

I do contend that it would be a better result (cvbs digital to digital) than going analog. Sure, not by a huge margin, but still an improvement.

[dogtopus]

Maybe, maybe not. I'm headed to bed, cuz it's late where I am, but the question is what we have in data coming across that ribbon cable. Again, if I'm reading it right, it says it is cvbs - but 10-bit encoded, which would make that a very unusual bitstream. That ribbon cable was assumedly supplying digital video to the top screen before, so I would assume somewhere in that tangle of data that rgb data is in there somewhere. Still a whole lot of assumptions on my part. I'd like to spend some time getting into the nuts and bolts of what is happening here. Otherwise I feel silly shooting from the hip.

I do contend that it would be a better result (cvbs digital to digital) than going analog. Sure, not by a huge margin, but still an improvement.

If I understand correctly the DS (or at least DS Lite) uses a 6-bit RGB interface by default for the screens. This project uses patched firmware to trick the display engine into outputting composite video signal (without the "PHY", which this project implements) instead. So if you are looking for RGB output this might not be appropriate. Also one of the goal for this project is to avoid FPGA, but it will probably be tricky to do composite (digital or not) to DVI/HDMI conversion without one. Off the shelf converters might be an option but those are likely to be one-chip solutions with built-in ADC and so because they want to be cheap.

Again I could be wrong. So devs feel free to correct me if I am.