MiSTer FPGA Forum

Hello.

I had a technical question on whether or not it's possible to alter the behavior of the pins on the "VGA Connector".
Currently, through configuration, there are a few options: RGBs, YPbPr and standard VGA.
Is it possible through FPGA programming to change the behavior of the pins that perform the YPbPr signal (when YPbPr mode is enabled)?

My hope is to have a new option where the 'greenish' cable might act like a single RCA video output cable, to go directly into older TVs.
And possibly have the red and blue one act like a chroma-luma pair, that might go into older computer monitors (e.g., Commodore 1702), or be adapted into an S-Video cable.

Is such a change technically possible for the FPGA implementation? Or is the pin behavior already determined by the Standard IO Board and unchangeable?

Thanks for your time and insight.

D.

For any confused readers: the need for composite/s-video is a problem mainly in the US/NTSC regions, as it seems only the late model (and high end) TVs had component inputs. (Here in Europe we have no trouble finding a TV with SCART-RGB.)

Most TVs in Europe have SCART, but not all of them support RGB.

With composite there is need for color encoding and I doubt there is sufficient resources to do that on the official hardware. Don't know whether combining Pb/Pr for S-video would be an issue or not. You'd also need readily available VGA to S-video breakout cables which I don't know how common there are..

Antionio Villenna had at some point made unofficial composite and svideo output boards. It sounded like the composite was finicky/unreliable but the s-video worked well at least.

I was able to find a board from Ali Express which was able to do the conversion.
https://aliexpress.com/item/502847877.html

More information in the tweet here, https://twitter.com/Darren_Janeczek/sta ... 4661055489 along with some sample images.
Since posting the message last year, I happened across two curbside CRT TVs with YPbPr input.

Hi. Nice find!

The adapter works with mister's vsync_adjust=2 ?
It add any perceived lag?