[sdiy] super-nice LED interface ..

[Colin f]

> .. and since the pulse-length determines the LED intensity, does it 
> also follow that 'dimmer LEDs' (pulsing less frequently) will scan 
> less frequently, leading to the obvious next step that with such a 
> setup, you would have to deal with varying scan rates .. ?

If you reduce the pulse width, you can increase the current, restoring the
same brightness.
As long as you don't exceed the average dissipation of an LED, they can be
given quite a kick.

I suppose a way to ignore ambient light would be to sample the current from
a detector diode before and during the on-pulse of the adjacent LED, and use
the difference between the readings. You might still have trouble with
changing levels of ambient light.

Cheers,
Colin f