Poulsbo SCH US15W, Graphics Frequency and maximum LVDS clock

[AMars5]

Dear All,

I'm using a custom platform with an AtomZ530 + US15W SCH (Poulsbo).

I would like to know if there is a correlation between US15W Graphics Frequency and maximum LVDS clock.

In fact here: /message/1422 http://embedded.communities.intel.com/message/1422 they say that the maximum LVDS clock (which, in turns, sets the maximum LVDS supported resolution) is 112MHz but different SKU "may have a lower maximum clock rate".

The only difference I've found between the Poulsbo SKU is the Graphics Frequency, which is 266MHz for US15X, 200MHz for US15W and US15L, and 100MHz for UL11L.

The Graphics frequency can also be configured with bootstrap pins, by choosing between 200 and 266MHz (which, I suppose, is available only for US15X).

Intel's docs are not so clear in this point and I cannot understand if Graphics Frequency only limits graphics hardware accelaration or also LVDS or SDVO output.

Does anybody have some more information on this?

Best Regards and Thanks in Advance,

Andrea

[HSche3]

Cannot give you definitive answer, but feeling "somebody reads and is interested". Educated guess from some years graphics card development + driver writing: Everything is possible. Even if a data sheet states there is no relation between two frequencies, but in reality data has to be passed between the 2 domains, depending on quality of implementation there might be unexpected practical limits (like one must be at least 2.5 of another).

I would say: Assume G.F. limits LVDS.

[FMcNu1]

Hello and welcome to the Intel® Embedded Community.

I have asked one of Intel's graphics technical experts to look at your question.

I also want to make you aware of a special place to go with questions like yours. The Intel® e-Help desk is staffed by Intel representatives who support select Intel embedded platforms including Intel Atom™ and associated chipsets including US15W.

To access e-Help, you need to be a Privileged member of the Intel® Embedded Community.

If you are not already a Privileged member, you can request an upgrade to your community account here:

https://edc.intel.com/My-Account.aspx https://edc.intel.com/My-Account.aspx

In addition to access to e-Help, Prvileged members may also access the confidential content within the Intel® Embedded Design Center, such as design documents, specifications, and training materials.

I hope this helps.

Felix

J. Felix McNulty

Community Moderator (Intel contractor)