In article <Pine.BSF.4.51.0405261632290.85840@vegeta.city-net.com> you write:
> user is wrong, and the best thing to do would be to remove the GETID
> implementation entirly (or have it return a description of the particular
> controller for potential informational messages) and just have one
> calibration per file.

This is more involved than I care to get into, especially since it's a
much more invasive change for a bunch of platforms I'm not familar with.
So at this point I intend to proceed roughly accoring to my original
plan, and you can always take on this other project separately.

>   I thought a vga frame buffer was available, but I guess not.  I was
> thinking of LCDs; if the device could be used on CRTs then mode does
> matter.

It matters on LCDs too. The unit I have supports scaling other modes to
its native resolution, and has per-mode adjustments for position, etc.
when scaling. If you configure in a text mode that is really scaled
640x480 or whatever, and then run X in native 800x480, things may be
significantly off.