Arduino Workshop, 2nd Edition

8 LED Numeric Displays and Matrices

In this chapter, you will

• Use MAX7219-based numeric LED displays
• Build your own digital stopwatch timer
• Use MAX7219-based LED matrix modules
• Build a scrolling text LED display

Although LED numeric displays (such as those found in contemporary digital alarm clocks) may not be on the bleeding edge of display technology, they are easy to read and—more importantly—easy to use with our Arduino boards.

You learned how to use one- and two-digit LED numeric displays in Chapter 6. However, using more than two digits at a time can become messy—there’s a lot more wiring, more control ICs, and so on to take care of. Fortunately, there’s a popular IC that can control up to 64 LEDs (eight digits of a numeric display) ...