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Blog Arduino based Christmas LED chain which automatically turns on when its dark outside. (Updated)
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  • Author Author: dragonboliero
  • Date Created: 2 Dec 2015 10:52 AM Date Created
  • Views 1327 views
  • Likes 4 likes
  • Comments 1 comment
  • open_source
  • led
  • arduino
  • christmas_chain
  • photoresistor
  • opensource
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Arduino based Christmas LED chain which automatically turns on when its dark outside. (Updated)

dragonboliero
dragonboliero
2 Dec 2015

Hello everyone,

 

I'm new here so I'm going to introduce myself. I'm Wojtek and I come from Poland, currently I''m 25 y.o. and I'm just starting my journey with Arduino. In the future I would like to share with you my projects and I hope you can provide some insight and constructive criticism.

 

Ok, so now lets hop into the project itself. It's rather basic because for now I don't have that many parts (just Arduino board, diodes, some resistors, tact switches and photoresistors). The chain uses photoresistor to read the brightness outside (that is why I recommend sticking it to the window or keeping it on the wall outside of it). Direct exposure to sunlight returns a value of ~15 - 25, during overcast day the value rises to 60 and when it gets relatively dark the returned value is ~650. That's why I decided to turn the chain on when the value is higher than 650.

 

You can see bare construction in the video below:

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That's how it looks in the bowl with Christmas glass balls:

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Parts required to assemble the chain:

 

1 - Arduino UNO

6 -  LED diodes

1 - photoresistor

6 - 280 ohm resistors (for diodes)

1 - 1K ohm resistor (for photoresistor)

Bunch of cables

 

You can find source code here: https://t.co/7fGqjvEFEq

Schematics are available here: Arduino based Christmas LED chain - Imgur

 

If you like what I'm doing you can follow me on Twitter https://twitter.com/milczarekw and subscribe on YouTube https://www.youtube.com/user/W0j45

 

I really appreciate your attention and I hope you've liked my entry.

 

 

UPDATE!!!

I've added potentiometer and a button to the circuit. Thanks to the potentiometer you can control brightness of the LEDs (they are connected through PWMs so they can act as analog pins), whereas the button controls which program is being used. Previously there was an infinite loop of three programs.

 

Here's a video presenting the new version:

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Schematics for the upgraded version: https://t.co/D2thcn5300

Source code: https://t.co/ikjVfC38FE

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  • DAB
    DAB over 10 years ago

    Nice post.

     

    Not bad for your first blog.

     

    DAB

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