[sdiy] super-nice LED interface ..

[Jason Tribbeck]

owner-synth-diy at dropmix.xs4all.nl wrote:

> but .. all LED's are on in that demo, so does this mean that
> the array has LED's that are 'off', but still being used as a
> detector, or does it mean that LED's can be used as detectors even
> when lit?

The LEDs are being pulsed - sometimes on, sometimes off. When they're
off, they can pick up the reflections from adjacent LEDs.

At least that's how I'd do it. I suppose if you pulsed it fast enough,
you could pick up its own reflection (I don't know physics to that level
- is there enough time to do it?)
-- 
Jason Tribbeck