Hacked Gadgets Forum

January 31, 2014

Use an LED as a Sensors

at 7:59 am. Filed under DIY Hacks, Electronic Hacks

Use an LED as a Sensors


Michael Beyhs has a new site called Electrical Engineering and More, his first project shows us how to Use an LED as a Sensor. LEDs are normally used to produce light but like many other electrical items it works a bit in the other direction, meaning that it will produce a small voltage when you shine light into it.

“How the code works:

  • Configure all analog inputs to outputs and pull low to turn on all red LEDs.
  • Turn one analog input pin into an actual Input and read the amount of light that is reflected into it.
  • Turn that input back into an output and continue on to next.
  • After all inputs have been read adjust the PWM of the blue LEDs according to the amount of light that was measured.
  • loop forever…”