Introduction: 16x8 LED Dot Matrix With MAX7219 Module

About: I am 47 years old and I live in Brazil. I am a Telecommunication / Electronics Engineer. twenty years acting in the industry of "Telecommunication and Networking". I like everything that engages Tech…

16x8 LED dot matrix with MAX7219 module

The objective of this project is: to show off the use of the module "MAX7219 dot matrix display module MCU control DIY"
In order to using it you will need the module that can be purchased on ebay:

And you will need the MaxMatrix libraries files (which are 3):

The sketch with the code can be found on the link below:

Or get all files at GitHub:

See in the attached picture the interconnection diagram between Arduino module and MAX7219 module (it was used only 2 MAX7219 modules in this case):

Arduino pin 13 (alternative: pin 10) connected to the CLK pin of the module MAX7219
Arduino pin 11 (alternative: pin 8) connected to pin DIN module MAX7219
Arduino pin 10 (alternative: 9 pin) connected to pin CS module MAX7219
GND and VCC (+5V)

To expand the number of modules, you should just connect Dout pin of one MAX7219 module with the Din pin of the another MAX7219 module... and so on.

The MAX7219 Dout pin is at the top of the module while Din pin is at the botton of the module.

Remembering that you can connect modules as you want, just connecting the output of one module with the input of the other and leaving the other signals in parallel.
In the sketch, you should to modify the parameter "maxInUse" for the amount of modules that you will use.

The video is just demo.
Remember that you can modify the messages in the code itself, or use the serial console to enter the message.

A second video using four MAX7219 modules.

New features were added to this project (on November 1st, 2014):

1 - 40x8 LED dot matrix;
2 - Start scrolling button;
3 - Speed control potentiometer;
4 - Intensity control

Some buttons were added as shown in schem above.

Here it is the new video showing these new features.


If you are having problem/errors with "prog_ucahr" in the PROGMEM statement line

Use the following:

1 - Used for older Arduino's IDE:

PROGMEM prog_uchar CH[] = {

2 - Used for newer Arduino's IDE:

PROGMEM const unsigned char CH[] = { //used for newer arduino's IDE

Feel free to send me comments/questions/problems.

Best Regards

Marcelo Moraes
Skype: marcelo.moraes

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