Light pens?

[Cameron Kaiser]

> > The VIC-II knows at any given point in time which pixel coordinate the
> > raster beam is currently at. Within the light pen is a sensor which can
> > pick up the presence of the beam. 
> 
> Does that mean the screen must be non-black for a light pen to work?

As far as the C64 goes, "black" isn't quite black. There's some residual
light generated, and the light pen will pick it up.

-- 
---------------------------------- personal: http://www.armory.com/~spectre/ --
 Cameron Kaiser, Floodgap Systems Ltd * So. Calif., USA * ckaiser at floodgap.com
-- Research is what I'm doing when I don't know what I'm doing. -- W. von Braun