SMT32 MAX7219 Dot Matrix
SMT32 MAX7219 Programmer – LED Dot Matrix is a shift chip register from MAXIM. It has long been used to display characters or running text.
Various types of dot matrix can be found in our environment, starting from small dot matrix to large size such as video tron. But how do I make the led matrix MAX7219 display text?
In this tutorial I want to give you a way of using 4 units of the MAX7219 STM32 8×8 dot matrix module which is controlled by a microcontroller.
It is important to know that in the market I found that there are two types of output chips for the STM32 variant namely STM32F103C and CKS32F103C.
They actually have the same STM32 architecture it’s just different vendors. The vendor STM32 is STMicroelectronics (USA), while the CKS32 vendor is CKSIC (China).
I used linux OS in this tutorial, if you want to know how to install and use STM32 on Linux, I suggest you read the previous page that is How to Program STM32 Blue Pill STM32F103C8T6 CKS32F103C8T6 Via USB Using Arduino on Linux (Ubuntu).
SMT32 Dot Matrix Wiring
For pin connections, I refer to the stm32projects blog. Dot Matrix or LED Matrix 7219 communicates with a microcontroller using MAX7219 I2C. For the library that I use in this project it is different as the stm32projects blog which uses the library from Nick Gammon. I use the MD Parola and MD MAX72xx libraries.
The connections are:
Download MD_Parola dan MD_MAX72XX Libraries
The MD_Parola and MD_MAX72xx libraries are libraries with different functions but are still under one developer, Majic Designs.
MD_Parola is used to create display effects and MD_MAX72xx to control its LED Matrix.
Display effects such as align text left, right or center, running text, text goes in and out, controls the brightness and appearance of animations, divides the display into zones, selects fonts as desired, merges several modules vertically and displays text and images in a way together.
Download the MD_PAROLA and MD_MAX72xx libraries
Hello Word Arduino Code
#include <MD_Parola.h>
#include <MD_MAX72xx.h>
#include <SPI.h>
#define HARDWARE_TYPE MD_MAX72XX::FC16_HW
#define MAX_DEVICES 4
#define CLK_PIN PA5
#define DATA_PIN PA7
#define CS_PIN PA8
MD_Parola P = MD_Parola(HARDWARE_TYPE, CS_PIN, MAX_DEVICES);
void setup(void)
{
P.begin();
P.displayText("Hello", PA_CENTER, 0, 0, PA_PRINT, PA_NO_EFFECT);
}
void loop(void)
{
P.displayAnimate();
}The results are:
That’s all and hopefully this article is useful.