Help from Gurus on modes and timing and frame buffers needed!

Kevin B. Hendricks khendricks at
Sat Nov 10 00:23:47 EST 2001

Hi Tony and Roman,

Thanks for your help with this!  The drawing and formulas helped me
understand things.  When I add to that nomenclature the nomenclature used
by the specific graphic card docs, things can get very confusing.  It
seems the VCLK and the DOT_CLOCK, and the PIXEL_CLOCK are all related but
they are ofter scaled differently (off by a factor of 10) and given as
inverses or one or the other.  Very confusing!

Anyway  One last question:

How are the Sync Flags determined?  I assume they either tell you if the
sync is an upward pulse or a downward pulse,  or which edge to trigger on
or something like that.

I see in the EDID block that SYNC_T = 1 but I have no idea how

                Flags   "-HSync" "-VSync"

are determined from that (or anything else).

Again any help would be greatly appreciated here.



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