> Aproximately 10% of the bottom of the screen duplicates the top ...
> So if I open a terminal window and move it off the top of the screen,
> this happens:
> 
> +-----------------------------+
> |                +----------+ |
> |                |          | |
> |                |   term   | |
> |                |          | |
> |                +----------+ |
> |                             |
> |                             |
> |-----------------------------+
> |                +----------+ |
> |                |          | |
> +-----------------------------+
> 
> So the top of the screen is repeated at the bottom. If I move the
> terminal window up as far as the cursor will go, then the top of it
> disappears completely:
> 
> +-----------------------------+
> |                |          | |
> |                |   term   | |
> |                |          | |
> |                +----------+ |
> |                             |
> |                             |
> |                             |
> |-----------------------------+
> |                |          | |
> |                |          | |
> +-----------------------------+

Interesting...  I'd guess that the 'wrap' is displayed because the
panel is ignoring the 'frame' signal because it isn't ready for it.
So probably the refresh rate it 1/2 the expected value.  This sort
of implies that the DMA is taking data from the wong place!  But
terminating at the correct one!!

So it doesn't look like a simple error in the config wrt the number
of blank lines required at the top of the screen (because the missing
data would (more or less) appear at the bottom.

Getting near time to consider what the HW spec says!

What is the display resolution? and colour depth?

10% of 640x480 is about 32k.....
I wonder if the chipset has some way of reading a colour pallete from
the start of the display buffer, it isn't unheard of...

	David

-- 
David Laight: david@l8s.co.uk