OBJECTIVE

In this project, we will use Arduino to MAX7219 matrix LED  module. MAX7219 uses SPI  serial protocol. It needs only three  I/O ports which can save a lot of I/O resources than other Maxtrix LEd module.

Parts and devices：

1 x Arduino UNO R3

1 x MAX72xx 8-digit LED display module

1 x USB cable

some jumper wires

3) Circuit graph

MAX7219_bb

4) Download library and sample code from following link

https://osoyoo.com/wp-content/uploads/2016/09/LedControl.zip. Unzip this file and move the unzipped folder to Arduino IDE library sub folder. Open the example file in the library.

Connection:
In above sample code, lc=LedControl(12,11,10,8) defines connection pins, details as following:
In function LedControl(int dataPin, int clkPin, int csPin, int numDevices), first parameter means data pin,
2nd parameter means clock pin, 3rd parameter means enable signal, last parameter means number of matrices(from 1 to 8)

Result

Load the code into Arduino IDE, the matrix will be turn on.

MAX7219 datasheet：MAX7219