Light sensor on XO-1.75
bert at freudenbergs.de
Tue Aug 30 09:50:47 EDT 2011
On 30.08.2011, at 01:38, Richard Smith wrote:
> On Mon, Aug 29, 2011 at 1:06 PM, Bert Freudenberg <bert at freudenbergs.de> wrote:
>> On 17.08.2011, at 17:24, Martin Langhoff wrote:
>>> Saadia Baloch (4):
>>> Driver to read Outdoor Light Sensor from EC on OLPC.
>> So this is exposed at
>> And it seems to sit "behind" the blinking left-most LED? And the blink rate is proportional to the light sensed? Why?
> Its proportional because that's how the sensor works. The amount of
> light changes the time to bleed off the charge stored in the diode
> when you reverse bias it.
Ah, so you use the LED itself to sense light? And then time how long a cycle takes in the EC? Awesome design!
This almost takes the cake over the analog mic hack.
- Bert -
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