> First all sorry top-posting...

Hmmm... I did that too.

> NuttX also have support to dot-matrix displays, see this "mp3 player" running NuttX:
>
> http://www.youtube.com/watch?v=A39rsIf07AA

I'm not certain, but I don't think that this example is using any of the NuttX graphics facilities.  I am not sure what he is doing, but the fonts don't look familiar (NuttX supports 17 different  Helvetica and Times Roman fonts) and the drawing certainly does not come from Nuttx.  I don't have any good demos of the graphics from NuttX but they are all rendered as "3-D" images.  I've attached the output of the button array unit test to give you a better idea of what I mean.

(That attached PNG came from here: http://nuttx.svn.sourceforge.net/viewvc/nuttx/trunk/NxWidgets/UnitTests/CButtonArray/cbuttonarray.png?view=log)

This button array, by the way, can used with a touchscreen as an on-screen keyboard (with the output going to an edit box).  "Widgets" like this have already been used to implement the complete GUI for a medical device.

Greg