#9 Arduino and LED 7-segment Displays Using a MAX7219 - Part 1

Introduction: #9 Arduino and LED 7-segment Displays Using a MAX7219 - Part 1

About: Arduino compatibles and other electronics for beginners! If you're getting started with the Arduino platform you'll be interested in my experiences as I investigate several 'building blocks' that can be atta...

Actually getting your Arduino to display something, whether that is a simple, single LED, an LED matrix or here an 8-digit LED display can be really satisfying.

Enter the mighty MAX7219 64-LED controller, that allows us not only to control an LED 64-LED matrix but also 8-digits of 64 segments (that's 8 segments per digit, if you include the decimal point).

Not only that, but the library I use that controls the MAX7219 allows individual numbers to be shown on any digit without all the usual faffing about that you might otherwise encounter trying to work out which individual segments make up the number 5, for example! So you just say (in your Arduino sketch) show me number 3 on digit 1, number 8 on digit 2, number 9 on digit 3... you get the idea?

In fact, there's so much to explore that it needs 3 videos to fully cover it all. Here's video Part 1, and I'll publish the remaining videos more quickly than usual so there is no huge time gap as that can be quite frustrating I know (a bit like waiting for the new season of CSI New York!).

Part 2 is here but won't make sense if you have not watched this (Part 1) first!

The 8-digit LED strip I use here (complete with that MAX7219 chip) is very good value for money if you can buy from the Far East via eBay. The only problem is that because the MAX7219 supports 8-digits (64 LEDs, remember) you can't buy it in any other configuration. So if you're after a 4-digit LED display you won't find a MAX7219 controlling that (it will probably be a TM1637 but that's a story for another video).

Enjoy the video, I hope you are 'edutained' and don't forget you can leave questions below.



    • Metalworking Contest

      Metalworking Contest
    • Water Contest

      Water Contest
    • Fix It! Contest

      Fix It! Contest

    6 Discussions


    2 years ago

    is there a link to parts 2 and 3 or just on youtube?

    also is there the possiblility of making these with the slanted didgits?

    5 replies

    Hello! Parts 2 & 3 will be added to the Instructables site very soon (or you can jump the queue and watch them - and several dozen more - on YouTube, of course).

    We are at the mercy of the manufacturers when it comes to what type of digits are available. Now, there is nothing stopping you from wiring up a MAX7219 to an LED digit strip of your choice, but it's more work than I'm prepared to put in given the price of these units!

    Thanks for that supportive comment. I hope the next two parts are too!

    It depends where you are in the world.

    If you can purchase from eBay then you are really spoiled for choice. Just search for MAX7219 and you will find hundreds of near-identical products. Go for a buyer that has a good feedback score. As a typical example (I am not endorsing this randomly chosen item: http://www.ebay.co.uk/itm/MAX7219-LED-Dot-matrix-8... )

    If you buy locally (or cannot access eBay) then expect to pay more (but you can also expect much faster delivery too!