In this Arduino tutorial we will learn how to control 8×8 LED Matrix using the MAX7219 driver and the Arduino board.
An LED matrix is a two dimensional array of LEDs that can be used to display symbols, characters or even images.LED matrix modules are one of the commonly used display devices and are used in major applications like electronic display panels and notification systems.
The project is based on the Arduino Uno microcontroller board. Out of the 14 available digital input / output pins on the Arduino Uno, we need only three pins to implement this project.
One pin provides the clock signal to the LED display driver IC (MAX 7219) while another pin is used to transmit the serial data to the IC for displaying on the LED matrix. The corresponding pins must be appropriately mentioned in the program.
An 8 x 8 LED matrix display is used in this project to display the information. LED matrices are available in different styles like single color, dual color, multi-color or RGB LED matrix.They are also available in different dimensions like 5 x 7, 8 x 8, 16 x 16, 32 x 32 etc. Based on the requirement we can get any one of these Dot Matrix Displays.
MAX 7219 driver IC
The LED matrix can be driven in two ways. They are parallel (where each row or column are sent with parallel data) and serial (where the data is sent serially and an IC is used to convert this serial data into parallel data).
MAX 7219 is a common cathode display driver with serial input and parallel output. It is used to interface microprocessors and microcontrollers with 64 individual LEDs (8 x 8 LED matrix for example has 64 LEDs), seven segment LED displays up to 8 digits or bar graph displays.
The 8 x 8 LED matrix is connected to the MAX 7219 as shown in the below circuit diagram and the data input is received from the Arduino board to the MAX 7219.
NOTE: Pre-wired MAX 7219 and 8 x 8 LED matrix modules are available in the market. They can be used for convenience.
The 64 LEDs are driven by 16 output pins of the IC. The question now is how is that possible.In general the maximum number of LEDs light up at the same time is actually eight. The LEDs are arranged as 8×8 set of rows and columns. So the MAX7219 activates each column for a very short period of time and at the same time it also drives each row. So by rapidly switching through the columns and rows the human eye will only notice a continuous light.
Copy this Code to your Arduino IDE and
Download Libraries and required files:
Practical Demo Video
: Watch this Video for Better Understanding including Code Explanation.
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