Hey guys, Welcome to Being Engineers. It has been long time since we posted any tutorial on this channel. Please excuse us for that. But we uploaded some videos in our youtube channel in this time. So you can check you those videos if you want. Channel link is given in the later part of this post.
In this video I will be showing step by step, how to make a binary clock. Yeah, I know. There are thousands of tutorials on internet telling the same thing. But this binary clock that we are going to make here is somehow different from the rest of it. This binary clock will be made using a technique called charlieplexing. we will be using around 20 leds to visually represent the time to us. And if you are familiar with the arduino board then you know that an Atmega328pu based boards doesn’t have that many digital pins to control 20 leds at once. So the obvious solution that comes out of this is multiplexing. In multiplexing we could have used matrix formation where we would need around 10 pins to control 20 leds in a formation of 4X6. But we will be going more deep and will use only 5 pins out of the arduino to control 20 leds. This technique is nothing but charlieplexing. With these few pins in use you can attach more components, sensors or relays on the unused I/O pins to add more functionality.
This will be a single tutorial, but on youtube there are 2 videos explaining the whole thing. The first video consists of the detailed explanation of the charlieplexing concept and how to use it in different scenarios. The sequel is the detailed binary clock making video. If you don’t want to read this tutorial, then you can also watch the videos to get the idea.”

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