Progressive Scan on 2600?

[ClausB]

Has anyone tried, in a game or demo, to output progressive scan video (480p) from a 2600? It would seem to be easy, just issue VSYNC every 525 scan lines instead of every 262, no?

[roland p]

That would result in 480p @ 29.97Hz instead of 59.94Hz. is that an accepted standard?

[+FujiSkunk]

For the typical 2600 connected to the typical HDTV using the typical antenna connection, it's not going to happen. For 480p video to work, you must give the TV an ATSC-encoded video signal, instead of an NTSC-encoded signal (or use something else entirely, like VGA). The Atari wasn't built to output ATSC. Yes, you will be giving the TV 525 scan lines per frame, but the TV will assume it is to display them using NTSC, and therefore you will get either half the picture or a really bad vertical roll.

 

Of course, the 2600 is capable of progressive video. All video game consoles from the 2600 up through the Playstation took advantage of quirks in the way conventional televisions process and display video to create a picture that doesn't appear interlaced. You could call the result "240p." Some digital displays actually detect this and also will switch to a "true" 240p presentation.

Edited September 30, 2008 by skunkworx

[ClausB]

For the typical 2600 connected to the typical HDTV using the typical antenna connection, it's not going to happen.

Not through the antenna (RF) connection, but maybe through composite or S-video (from a modded 2600)? Don't EDTVs and HTDVs support 480p30 through YPbPr component inputs (for progressive-scan DVD players)? I know that the color encoding is different between NTSC (composite or S-video) and YPbPr (component) but I thought maybe the progressive scan mode might apply to both. I suppose you could feed the modded 2600 composite video to the Y component input and get 480p30, although without color.

[supercat]

Has anyone tried, in a game or demo, to output progressive scan video (480p) from a 2600? It would seem to be easy, just issue VSYNC every 525 scan lines instead of every 262, no?

 

480P is 60fps, so the horizontal scan rate would have to be doubled. One might be able to use the VSYNC register to generate extra horizontal sync pulses in the middle of each line, but I really can't see that as being practical for anything.