|
 Project
11
'Programmable LED'
04.22.09
This project is a tiny blinking device. This
circuit is build in, so called, free form. That means there is no PCB (Printed
Circuit Board) involved. Components are soldered directly to each other.
The
blinking sequence can be reprogrammed with the use of a flash light. It detects
changes in lighting and records these changes and finally plays them back. It is
one of the simplest things you can do with a microcontroller.
How does it work
The LDR (Light Dependent Resistor) is used as input sensor
to detect the light changes. It is attached to an ADC (Analog Digital
Converter) port of the micro controller.
If the controller detects short light changes
(dark, bright, dark or the other way round) it switches into recording mode.
It records up to 10 seconds with 40 samples per second. Then it switches
back to playback mode and plays the recorded sequence.
|
