about LCD?

cat kit kitcat355 at gmail.com
Tue Sep 23 20:55:01 CDT 2008


Hello Caglar,
What exactly you set in the bootargs? because I can't get my NTSC/PAL
to the 800x480 (or 800x576 perhaps) LCD working.

> Jaswinder Singh wrote:
>
> > Hello Caglar,
> >
> > On Wed, 2008-09-17 at 14:38 +0300, Caglar Akyuz wrote:
> >
> >>> Have you added support for 800x480 prgb on decode, encode and encodedecode demos ?
> >>>
> >> I've been playing with them for a couple of days. In fact only change needed is in
> >> WaitForVsync function since LCD is updated almost at double rate compared to NTSC/PAL.
> >> You should wait two syncs instead of one. I learned this nice trick from a post in
> >> the list. Key point to success is to adjust video framebuffers for 800x576 so that demo
> >> ioctls won't complain. I disabled OSD ioctls in the demos so that I can adjust my OSD frame
> >> buffers for my native resolution.(800x480)
> >

Not sure how you adjust the frame buffers to the 800x480, you mean set
it through fbset? however the fbset doesnt work properly if I use the
wrong bootargs. I got rgba 8/0, 8/0, 8/0, 8/0 for my /dev/fb/0 when
fbset -i -fb /dev/fb/0 and I got rgba 0/0, 0/0, 0/0, 0/0 in another 3
framebuffer /dev/fb/1 /dev/fb/2 /dev/fb/3 which I think something is
not correct, futhermore the pixclock shows 0 when I set it to 800x576
Any idea what I done wrong?

> > Are you using DVSDK_1_30_00_40 or higher ?
> >
>
>
> Yes.
>
> > In DVSDK_1_30_00_40, dvevm demos do not start if resolution is not NTSC
> > or PAL, Have you added support for 800x480 prgb ?
> >
>
> > dvsdk_1_30_00_40/demos/dm6446/decode/decode.h :
> > /* Scaling factors for the video standards */
> > #define NOSTD               0
> > #define PALSTD              12
> > #define NTSCSTD             10
> >
>
>
> Seems like I forgot somethings. I hope there are not others :)
>
> I changed the detectVideoStandard function to set PALSTD always.
> It does't matter as long as you adjust sync wait and boot args
> correctly.
>
> Thanks,
> Caglar

Thanks
Kit


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