How to output to a TV in 15khz?

[Jack Burton]

I have a simple goal:

To output a resolution from my computer of 256x240 at 60hz to my television.

How can I do this?

The reason I want to do this is to play NES games in their native resolution on my television.

Also, if televisions are not capableof displaying this resolution, then how would I display the same resolution that an NES outputs to a TV?

[Jack Burton]

I will reply to my own post.

I have thought of buying a colorspace transcoder, that is, a VGA to Component converter.  However, I am not sure what resolutions these devices support.  And I am concerned that it would result in a delay between input from the controller and what is displayed on screen.

I have also been looking for a graphics card that does Component out without controlling the resolution.  I know that most graphics cards with S-Video and component out scale whatever resolution you choose to 640x480 or 800x600.  So even if I could set my software to 256x240, the graphics card will just scale it back up and defeat my goal.  Are there graphics cards that are specifically made for outputting component video without scaling?

I would be even more pleased if I could somehow find a card or cards that has the ability to output composite and coaxial signals.  I would need these if I wanted my emulation box to be truly portable and able to connect to any television.

[ahofle]

Unless you live in Europe and have a TV with an SCART input, you are pretty much out of luck unfortunately.  The problem is not that the TV doesn't handle the resolution (it's exactly the same tube as an arcade monitor!) it's the fact that it is requiring an NTSC signal which is 640x480i.  Other than options like converters, you would need a new chassis for the TV (see this thread: http://forum.arcadecontrols.com/index.php?topic=5448.0).

[Jack Burton]

So why is it that my xbox can't just send 640x480i to my tv to make it look exactly like the NES looked?  With all the filters off it still looks completely wrong.

[MonMotha]

Many NTSC TVs will happily display 240 line progressive video as long as the timings are similar to NTSC (just progressive).  Getting the signal to it can be a pain.  Video cards with s-video outputs won't work fo ryou because htey are designed to just crush and scale everything until it fits, paying no attention to how good it actually looks.  Your best bet is a RGB to YPbPr colorspace converter ("transcoder") if your TV has YPbPr component inputs.  Just make sure you don't accidentally feed it 480p if that isn't a supported mode.  Hook up your colorspace converter and proceede as if the TV is an arcade monitor.  If you only have composite, you can get RGB to NTSC converters.  Quality varies, and some might get confused with progressive video, but they are out there.

[Jack Burton]

Cool.

My goal is to essentially build a box that emulates various systems.  So it needs to be able to connect to just about any kind of TV.  If I have to take a RGB to NTSC converter apart and mount it inside the case, then so be it.