1280x1024@60 Resolution - Anybody running this?

dave higton wrote:

Quoting Koen Kooi<koen@beagleboard.org>:

> Quoting Koen Kooi<koen@beagleboard.org>:
>
>> The supported pixclock is>170MHz on beagle
>
> Where is this specified?

In the omap3 TRM.

> I have always understood that the maximum pixel rate was
> 83 MHz (original BB).

If you use the DSI PLL you get a 173MHz pixclock. Angstrom enabled that as
default in the kernel, and has done that for years now. I have 1080p24
working nicely on a C4.

But 1920 x 1080 x 24 fps is a net rate of 48384000 triads/sec,
isn't it, so even when overheaded for the flyback periods,
it only requires a pixel clock in the ballpark of 50 MHz,
doesn't it?

no, the H and V blanking periods are huge...

1080p24: 1920x1080@24 in 2750x1125 -> 74.25 MHz

Quoting Vladimir Pantelic <vladoman@gmail.com>:

dave higton wrote:
> Quoting Koen Kooi<koen@beagleboard.org>:
>
>>
>>
>> > Quoting Koen Kooi<koen@beagleboard.org>:
>> >
>> >> The supported pixclock is>170MHz on beagle
>> >
>> > Where is this specified?
>>
>> In the omap3 TRM.
>>
>> > I have always understood that the maximum pixel rate was
>> > 83 MHz (original BB).
>>
>> If you use the DSI PLL you get a 173MHz pixclock. Angstrom enabled that
as
>> default in the kernel, and has done that for years now. I have 1080p24
>> working nicely on a C4.
>
> But 1920 x 1080 x 24 fps is a net rate of 48384000 triads/sec,
> isn't it, so even when overheaded for the flyback periods,
> it only requires a pixel clock in the ballpark of 50 MHz,
> doesn't it?

no, the H and V blanking periods are huge...

1080p24: 1920x1080@24 in 2750x1125 -> 74.25 MHz

OK, but it's still way below 173 MHz. It's even below 83 MHz,
so 1080p24 would still work even if the pixel clock were
limited to the 83 MHz figure that I had in mind, wouldn't it?
It's not a difficult screen mode to achieve.

Dave

Hi Koen:
Could you indicate how I should adjust the file boot.scr for a
resolution of 1680x1050, for a DVI monitor ViewSonic brand
Thanks
Carlos