In the previous chapter, you learned how to build a digital clock using 4-digit 7-segment and OLED display modules. In this chapter, we will learn how to work with an LED dot matrix display and focus on 8 x 8 LEDs' model. These LEDs can have monochrome color or RGB color. To simplify the problem, we will use monochrome color on the LED dot matrix display module.

In an LED matrix display, multiple LEDs are connected together in row and columns. This connection is established to reduce the number of pins needed to manipulate them. For instance, the 8 x 8 LED dot matrix is shown in the following figure:

In the preceding figure, if R3 is in 1 logic and C2 is in 0 logic, the LED on line 3 column 3 will be turned on. The characters will be displayed by fast scanning each row and column. For illustration, if we need to display the character A, we can draw the following figure on our dot matrix:

An MCU, which wants to work with 8 x 8 LED dot matrix display...