[sdiy] Alternatives to Faders, level display

[Ingo Debus]

Am 07.03.2007 um 16:08 schrieb Edward King:

> The only issue Ive found is that the level display is inadequate  
> for fine control.

I'm wondering if a "moving dot" display with two LEDs with different  
brightnesses on at a time would be useful for such a thing. Here's a  
table showing the brigtnesses for three LEDs and nine level steps  
using four different brightnesses (view with fixed font):


level  0    1    2    3    4    5    6    7    8
------------------------------------------------
led3   0    0    0    0    0    0.25 0.5 0.75  1
led2   0    0.25 0.5  0.75 1    0.75 0.5 0.25  0
led1   1    0.75 0.5  0.25 0    0    0    0    0

Get the idea? If a LED could only be on or off, three LEDs could only  
display three level steps.
Here the brightness sum is always 1, if a sum nonequal to 1 were  
allowed even more steps would be possible. Controlling the brightness  
of LEDs is probably not difficult if they are multiplexed anyway.

Ingo