GP2X Non-Interlaced Tv Output Signal


f-cycles

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Looking to the forum, it's seem that the activities for gp2x did reduce since two years ago... :( I did master the TV output signal on the gp2x up to some extend. There is one thing which I try to do but I never been able to have a stable image on screen is to configure the CX25874 to output a non-interlaced TV output signal. In order to have 60 FPS on ODD or EVEN frame only. (just like a old video games) :)

Best regards,
 
My best result so far, it's something which work over 95% of the time. But in some cases when I switch to non-interlaced signal, the TV output signal is still valid (I don't see video 2 on my TV :p) but the image display is a solid black.

I found tonight how to get rid of an artefact by modifying T3(DESTR)...

My guess is that I should modify the registers I set during a specific timing zone... from the chances of success I have my guess is during the active region of the screen... But looking to my routine that switch between LCD 320x240 to TV-Out 720x480, beside turning off all interupts and re-enabling them and few delay of 10ms for the cx25784.

I admit at this point in time, it's bit blurry in my head.

Adjusting the width of the image seem even more difficult task... as I guess I should modify some clock!? Hum.. currently I am using the hw scaler on the rgb layer, but I would prefer to modify the tv-out signal and have the scaling effect on all layers and keep inactive the scaler (at least for TV display).

I also wonder if outputing a signal at 1024x768 on s-video will allow me to get a better quality than a 720x480 (720x588 pal) on a HDTV?

You can see a picture I took from a tool of my low-level library running on my TV...
http://www.twitpic.com/qy4b9

I switch back to my debugguer which support usb keyboard to peek and poke the mmsp2 and cx25874...
but most of the time, I need to re-compile and try because there are some critical operations.

I though to get a release prior to working back on the display thing, but I consider the non-interlaced video display to be something essential! ;)
 
f-cycles said:
RESEARCH COMPLETED WITH SUCCESS! :D

Hehe I know what it is like to mess with these TV registers it will drive you crazy. I spent a week last year trying to get TVout better for all apps on the GP2X through the Open2X firmware and had quite a bit of success on both the YUV and RGB layers. Didn't experiment with 720x480 resolutions though.
 
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If your video drivers are like mine, they let you change the zoom on the TV-out from the Control Panel. This should make it possible to move the control buttons into the visible area. Also, some TVs have picture adjustment controls on them.
 
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