Matrix7219 displays scrambled display on ESP32C mini

galacticobmg · June 25, 2024, 5:11pm

Hi everybody,
today I would like to solve a strange problem with 7219Matrix displays which I am using on several projects and often get the same problem: The output on the Matrix gets scrambled after a few minutes working well. Actually on my NANO processors they work pretty fine but on any ESP32 processor I get this strange effect which I show on the pictures below: First the working Version on a ATmega 328P NANO:

code for this Version is

#include <SPI.h>
#include <Adafruit_GFX.h>
#include <Max72xxPanel.h>
#include <DS3231.h>
#include <Wire.h>
#include <SSD1306Ascii.h>
#include <SSD1306AsciiAvrI2c.h>

int pinMin = 10;
int pinHour = 9;
int pinLight = 5; 
int GetBtn = 6; // left button
int SetBtn = 7; // right button
//Din connects to pin 11
//CLK connects to pin 13

int numberOfHorizontalDisplays = 10;
int numberOfVerticalDisplays = 1;

int HourPosRect5[4] = {41,51,61,71};
int HourPosRect1[4] = {1,11,21,31};

int MinPosBars[11] = {40,43,46,51,54,57,62,65,68,73,76};
int MinPosRect[4] = {1,11,21,31};
int yPos = 0;
int Hori = 2; // 2 for bars 8 for rectangle
int Vert = 8;
int numHour5;
int numHour1;
int numMinBars;
int numMinRect;
int H5rect;
int H1rect;
int Mbar;
int Mrect;

unsigned long currentMillis;
unsigned long startTimer;
bool LightON;
byte Year ;
byte Month ;
byte Date ;
byte DoW ;
byte Hour ;
byte Minute ;
byte Second ;
bool Century=false;
bool h12 ;
bool PM ;

const char *WeekDay[] = { "Lunes", "Martes", "Miercoles", "Jueves", "Viernes", "Sabado","Domingo" };
//const char *Mon[] = {"XXX", "ENE", "FEB", "MAR", "ABR", "MAY", "JUN", "JUL", "AGO", "SEP", "OCT", "NOV", "DIC"};
bool END;
int Block[7];
int dispPos=0;
int setVal=0;

#define HARDWARE_TYPE MD_MAX72XX::PAROLA_HW
#define MAX_DEVICES  20
#define CLK_PIN   13  // or SCK
#define DATA_PIN  11  // or MOSI
#define pinMin    10  // Minute Matrix
#define pinHour    9  // Hour Matrix

SSD1306AsciiAvrI2c win;
Max72xxPanel matMin = Max72xxPanel(pinMin, numberOfVerticalDisplays, numberOfHorizontalDisplays);
Max72xxPanel matHour = Max72xxPanel(pinHour, numberOfVerticalDisplays, numberOfHorizontalDisplays);

DS3231 Clock;

void setup() 
{
  pinMode(pinLight, OUTPUT);
  pinMode(GetBtn, INPUT);
  pinMode(SetBtn, INPUT);
  
  matMin.setIntensity(2);
  matMin.setRotation(0);
  matHour.setIntensity(2);
  matHour.setRotation(0);

  matMin.fillScreen(LOW); matMin.write();
  matHour.fillScreen(LOW); matHour.write();


  Wire.begin();
   win.begin(&SH1106_128x64, 0x3c);
   win.setFont(System5x7);
   win.clear();
   
 Clock.setClockMode(false);
 
 //Clock.setSecond(0);
 //Clock.setMinute(54);
 //Clock.setHour(18);
 
    Block[0] = Clock.getYear(), DEC;
    Block[1] = Clock.getMonth(Century), DEC;
    Block[2] = Clock.getDate(), DEC;
    Block[3] = Clock.getDoW(), DEC;
    Block[4] = Clock.getHour(h12,PM), DEC;
    Block[5] = Clock.getMinute(),DEC;
    Block[6] = Clock.getSecond(),DEC;

   win.println("RTC hora actual es ");
   win.println("---------------------");
  
   if(Block[2]<10) {win.print("0");}
   win.print(Block[2]);
   win.print(".");
   if(Block[1]<10) {win.print("0");}
   win.print(Block[1]);
   win.print(". 20");
   win.print(Block[0]);
   win.print(" ");
   //Clock.setClockMode(false);
   win.print(Block[4]); 
   win.print(":");
   win.print(Block[5]);
   win.print(":");
   win.println(Block[6]);
   win.println(" ");
   win.println("<- Boton: ajuste hora");
   win.println(" ");
   win.println("Boton -> start reloj"); 

  while (!digitalRead(GetBtn) && !digitalRead(SetBtn)) {;}

  if(digitalRead(SetBtn)) {analogWrite(pinLight, 100);}

// **************** NOW INPUT DATA *******************
   if (digitalRead(GetBtn))
   {
    win.clear();
    delay(200);
    InputData();
   }
  win.clear();

 // Set Clock Condition
 
 //analogWrite(pinLight, 100);

 delay(1000); 
}

void loop() 
{
  startTimer=millis();
  if (startTimer > currentMillis+1000)
   {
    showTime();
    if (LightON)
     { LightON=false; analogWrite(pinLight, 0);}
    else
     { LightON=true; analogWrite(pinLight, 100);} 
    currentMillis=millis(); 
   }
   

  matMin.fillScreen(LOW);
  matHour.fillScreen(LOW);
  
  Hour = Clock.getHour(h12,PM);
  Minute = Clock.getMinute();

  // calculate Hour fields
  numHour5 = Hour/5;
  numHour1 = Hour-(numHour5*5);
   
  //calculate Minute bars
  numMinBars = Minute/5;
  numMinRect = Minute-(numMinBars*5);

  // draw Hour bars and fields
  Hori=8;
   for(H5rect=0; H5rect<numHour5; H5rect++)
   {
    matHour.drawRect(yPos, HourPosRect5[H5rect], Vert, Hori,HIGH);
    matHour.drawRect(yPos+1, HourPosRect5[H5rect]+1, Vert-2, Hori-2,HIGH);
   }  
    for(H1rect=0; H1rect<numHour1; H1rect++)
   {
    matHour.drawRect(yPos, HourPosRect1[H1rect], Vert, Hori,HIGH);
    matHour.drawRect(yPos+1, HourPosRect1[H1rect]+1, Vert-2, Hori-2,HIGH);
   }  
  Hori = 2;
  for(Mbar=0; Mbar < numMinBars; Mbar++)
   {
    matMin.drawRect(yPos, MinPosBars[Mbar], Vert, Hori,HIGH);
   }
  Hori=8;
  for(Mrect=0; Mrect<numMinRect; Mrect++)
   {
    matMin.drawRect(yPos, MinPosRect[Mrect], Vert, Hori,HIGH);
    matMin.drawRect(yPos+1, MinPosRect[Mrect]+1, Vert-2, Hori-2,HIGH);
   } 
   matMin.write();
   matHour.write();
}

void InputData()
  {
       while (setVal<7) // input date/time values
        {
        if (digitalRead(GetBtn)) // ajust actual value
         {
          Block[setVal]++ ;
          if (Block[0] > 32) {Block[0] = 22;}
          if (Block[1] > 12) {Block[1] = 1;}
          if (Block[2] > 31) {Block[2] = 1;}
          if (Block[3] > 7 ) {Block[3] = 1;}
          if (Block[4] > 23) {Block[4] = 0;}
          if (Block[5] > 59) {Block[5] = 0;}
          if (Block[6] > 59) {Block[6] = 0;}      
          
          delay(100);      
         }
         
         if (digitalRead(SetBtn)) // set value and goto next 
         {
          setVal++;
          delay(100);
         }  
         showInput();
         delay(200);    
        } // ready input date/time values 0 to 5
     
    win.clear();
    win.setCursor(0,1);
    win.print("Ajuste Hora listo");
    while(!digitalRead(SetBtn)) {;}
    
    SetClock();
  }


void showInput()
 {
  win.home();
  win.setFont(System5x7);
  win.println("ingresar fecha/hora");
  win.println("---------------------");

  win.setCursor(0,2);
  win.println("Ano   Mes  Dia  Sem");
  for (dispPos=0; dispPos<4; dispPos++)
  {
    win.setCursor((dispPos*34),3);
    if (dispPos==setVal) {win.setInvertMode(true);} else {win.setInvertMode(false);}
    win.setFont(cp437font8x8);
    if (Block[dispPos] < 10) {win.print("0"); win.print(Block[dispPos]);} else  {win.print(Block[dispPos]);}
    win.setFont(System5x7);
  }
  win.setInvertMode(false);
  win.setCursor(0,5);
  win.print("Hora Minuto Segundo");
    for (dispPos=4; dispPos<7; dispPos++)
  {
  win.setCursor(((dispPos-4)*36),6);

  if (dispPos==setVal) {win.setInvertMode(true);} else {win.setInvertMode(false);}
  win.setFont(cp437font8x8);
  if (Block[dispPos] < 10) {win.print("0"); win.print(Block[dispPos]);} else  {win.print(Block[dispPos]);}
  win.setFont(System5x7);
  //delay(100);
  }
  win.setInvertMode(false);
 } 

void SetClock()
  {
   Clock.setClockMode(false);  // set to 24h
   Clock.setSecond(Block[6]);
   Clock.setMinute(Block[5]);
   Clock.setHour(Block[4]);
   Clock.setDoW(Block[3]);
   Clock.setDate(Block[2]);
   Clock.setMonth(Block[1]);
   Clock.setYear(Block[0]);

   win.setCursor(30,3);
   win.print("* LISTO *");
   delay(1000);
   win.clear();      
  }

void showTime()
{
    
   win.setFont(cp437font8x8);
   win.setCursor(0,0);
   win.print(Clock.getDate(), DEC);
   win.print(".");
   win.print(Clock.getMonth(Century), DEC);
   win.print(".");
   //win.print(Clock.getYear(), DEC);
   win.print("             ");
   win.setCursor(60,0);
   win.print(WeekDay[Clock.getDoW()-1]);

   win.setFont(fixed_bold10x15);
   win.setCursor(20,4);
   if ((Clock.getHour(h12, PM)) < 10){win.print("0");}
   win.print(Clock.getHour(h12, PM));
   win.print(":");
   if ((Clock.getMinute()) < 10){win.print("0");} 
   win.print(Clock.getMinute());
   win.print(":");
   if ((Clock.getSecond()) < 10){win.print("0");}
   win.print(Clock.getSecond());
   win.print("  ");
}

The ESP32 Version is this one:

#include <SPI.h>
#include <Adafruit_GFX.h>
#include <SH1106Wire.h>
#include <Max72xxPanel.h>
#include <DS3231.h>
#include <Wire.h>
int pinMin = 7;
int pinHour = 10;
int pinLight = 2; 
int GetBtn = 0; // left button
int SetBtn = 1; // right button
//Din connects to pin 6
//CLK connects to pin 4

int numberOfHorizontalDisplays = 10;
int numberOfVerticalDisplays = 1;

int HourPosRect5[4] = {41,51,61,71};
int HourPosRect1[4] = {1,11,21,31};

int MinPosBars[11] = {40,43,46,51,54,57,62,65,68,73,76};
int MinPosRect[4] = {1,11,21,31};
int yPos = 0;
int Hori = 2; // 2 for bars 8 for rectangle
int Vert = 8;
int numHour5;
int numHour1;
int numMinBars;
int numMinRect;
int H5rect;
int H1rect;
int Mbar;
int Mrect;

unsigned long timer1;
unsigned long timer2;
bool LightON;
byte Year ;
byte Month ;
byte Date ;
byte DoW ;
byte Hour ;
byte Minute ;
byte Second ;
bool Century=false;
bool h12 ;
bool PM ;

const char *WeekDay[] = { "Lun", "Mar", "Mie", "Jue", "Vie", "Sab","Dom" };
const char *Mon[] = {"XXX", "ENE", "FEB", "MAR", "ABR", "MAY", "JUN", "JUL", "AGO", "SEP", "OCT", "NOV", "DIC"};
bool END;
int Block[7];
int dispPos=0;
int setVal=0;
int cy;
int cx;
int line = 10;
int chra = 7;
int cleft = 15;


//SSD1306AsciiAvrI2c win;
SH1106Wire win(0x3c, SDA, SCL);
Max72xxPanel matMin = Max72xxPanel(pinMin, numberOfVerticalDisplays, numberOfHorizontalDisplays);
Max72xxPanel matHour = Max72xxPanel(pinHour, numberOfVerticalDisplays, numberOfHorizontalDisplays);

DS3231 Clock;

void setup() 
{
  pinMode(pinLight, OUTPUT);
  pinMode(GetBtn, INPUT);
  pinMode(SetBtn, INPUT);
  
  matMin.setIntensity(2);
  matMin.setRotation(0);
  matHour.setIntensity(2);
  matHour.setRotation(0);

  matMin.fillScreen(LOW); matMin.write();
  matHour.fillScreen(LOW); matHour.write();


  Wire.begin();

   win.init();
   win.flipScreenVertically();
   win.setContrast(255);
   win.setColor(WHITE);
   win.cls();

   //win.setFont(ArialMT_Plain_10);
   //win.setTextAlignment(TEXT_ALIGN_LEFT);
   
 Clock.setClockMode(false);
 
 //Clock.setSecond(0);
 //Clock.setMinute(54);
 //Clock.setHour(18);
 
    Block[0] = Clock.getYear(), DEC;
    Block[1] = Clock.getMonth(Century), DEC;
    Block[2] = Clock.getDate(), DEC;
    Block[3] = Clock.getDoW(), DEC;
    Block[4] = Clock.getHour(h12,PM), DEC;
    Block[5] = Clock.getMinute(),DEC;
    Block[6] = Clock.getSecond(),DEC;

   cx=cleft;cy=0;win.drawString(cx,cy,"RTC actual time is :");
   cy=line;win.drawString(cx,cy,"---------------------------------");
   showTime();

   cy=5*line;cx=cleft-15;
   win.drawString(cx,cy,"<- adjust Hour:Start Clock ->");
   win.display();
  while (!digitalRead(GetBtn) && !digitalRead(SetBtn)) {;}

  if(digitalRead(SetBtn)) {analogWrite(pinLight, 100);}

// **************** NOW INPUT DATA *******************
   if (digitalRead(GetBtn))
   {
    win.cls();
    delay(200);
    InputData();
   }
  //win.cls();

 // Set Clock Condition
 
 //analogWrite(pinLight, 100);

 delay(1000); 
}

void loop() 
{
  timer2=millis();
  if (timer2 > timer1+1000)
   {
    win.clear();
    showTime();
    win.display();
    if (LightON)
     { LightON=false; analogWrite(pinLight, 0);}
    else
     { LightON=true; analogWrite(pinLight, 100);} 
    timer1=millis(); 
   }

 
  matMin.fillScreen(LOW);
  matHour.fillScreen(LOW);
  
  Hour = Clock.getHour(h12,PM);
  Minute = Clock.getMinute();

  // calculate Hour fields
  numHour5 = Hour/5;
  numHour1 = Hour-(numHour5*5);
   
  //calculate Minute bars
  numMinBars = Minute/5;
  numMinRect = Minute-(numMinBars*5);

  // draw Hour bars and fields
  Hori=8;
   for(H5rect=0; H5rect<numHour5; H5rect++)
   {
    matHour.drawRect(yPos, HourPosRect5[H5rect], Vert, Hori,HIGH);
    matHour.drawRect(yPos+1, HourPosRect5[H5rect]+1, Vert-2, Hori-2,HIGH);
   }  
    for(H1rect=0; H1rect<numHour1; H1rect++)
   {
    matHour.drawRect(yPos, HourPosRect1[H1rect], Vert, Hori,HIGH);
    matHour.drawRect(yPos+1, HourPosRect1[H1rect]+1, Vert-2, Hori-2,HIGH);
   }  
  Hori = 2;
  for(Mbar=0; Mbar < numMinBars; Mbar++)
   {
    matMin.drawRect(yPos, MinPosBars[Mbar], Vert, Hori,HIGH);
   }
  Hori=8;
  for(Mrect=0; Mrect<numMinRect; Mrect++)
   {
    matMin.drawRect(yPos, MinPosRect[Mrect], Vert, Hori,HIGH);
    matMin.drawRect(yPos+1, MinPosRect[Mrect]+1, Vert-2, Hori-2,HIGH);
   } 
   matMin.write();
   matHour.write();
 
}

void InputData()
  {
       while (setVal<7) // input date/time values
        {
        if (digitalRead(GetBtn)) // ajust actual value
         {
          Block[setVal]++ ;
          if (Block[0] > 32) {Block[0] = 22;}
          if (Block[1] > 12) {Block[1] = 1;}
          if (Block[2] > 31) {Block[2] = 1;}
          if (Block[3] > 7 ) {Block[3] = 1;}
          if (Block[4] > 23) {Block[4] = 0;}
          if (Block[5] > 59) {Block[5] = 0;}
          if (Block[6] > 59) {Block[6] = 0;}      
          
          delay(100);      
         }
         
         if (digitalRead(SetBtn)) // set value and goto next 
         {
          setVal++;
          delay(100);
         }  
         showInput();
         win.display();
         delay(200);    
        } // ready input date/time values 0 to 5
     
    win.cls();
    cx=2*chra; cy=line;
    win.drawString(cx,cy,"adjust hour ready");
    win.display();
    while(!digitalRead(SetBtn)) {;}
    
    SetClock();    
  }


void showInput()
 {
  win.clear();
  cx=chra; cy=0;
  win.drawString(cx,cy,"input date and time");
  cx=chra; cy=line; win.drawString(cx,cy,"---------------------");

  cx=chra; cy=2*line;
  win.drawString(cx,cy,"Year    Mon    Day   DoW");
  for (dispPos=0; dispPos<4; dispPos++)
  {
    cx=dispPos*30+chra+8; cy=3*line; //    win.setCursor((dispPos*34),3);
    //if (dispPos==setVal) {win.setColor(WHITE);} else {win.setColor(BLACK);}
    if (dispPos==setVal) {win.drawRect(cx-2,cy+1,16,11);}
    if (Block[dispPos] < 10) {win.drawString(cx,cy,"0"); cx+=chra; win.drawString(cx,cy,String(Block[dispPos]));} else  {win.drawString(cx,cy,String(Block[dispPos]));}
  }
  cx=chra; cy=4*line; //win.setCursor(0,5);
  win.drawString(cx,cy,"Hour   Minute   Second");
    for (dispPos=4; dispPos<7; dispPos++)
     {
      cx=(dispPos-4)*40+chra; cy=5*line; //win.setCursor(((dispPos-4)*36),6);
      if (dispPos==setVal) {win.drawRect(cx-2,cy+1,16,11);}
      //win.setFont(cp437font8x8);
      if (Block[dispPos] < 10) {win.drawString(cx,cy,"0"); cx+=chra; win.drawString(cx,cy,String(Block[dispPos]));} else  {win.drawString(cx,cy,String(Block[dispPos]));}
      //win.setFont(System5x7);
      //delay(100);
     }
 } 

void SetClock()
  {
   Clock.setClockMode(false);  // set to 24h
   Clock.setSecond(Block[6]);
   Clock.setMinute(Block[5]);
   Clock.setHour(Block[4]);
   Clock.setDoW(Block[3]);
   Clock.setDate(Block[2]);
   Clock.setMonth(Block[1]);
   Clock.setYear(Block[0]);

   win.cls();
   cx=2*chra; cy=0;   //win.setCursor(30,3);
   win.drawString(cx,cy,"* Clock time set to : *");
   showTime();
   win.display();
   delay(2000); 
  }

void showTime()
{
   cx=cleft;cy=2*line;
   win.drawString(cx,cy,WeekDay[Clock.getDoW()]);cx+=3*chra;
   if(Clock.getDate()<10) {win.drawString(cx,cy,"0");cx+=chra;}
   win.drawString(cx,cy,String(Clock.getDate()));
   if(Clock.getDate()>9) {cx+=chra;}
   cx+=chra;win.drawString(cx,cy,".");
   cx+=chra; win.drawString(cx,cy,Mon[Clock.getMonth(Century)]);cx+=2*chra;
   if(Block[1]>9) {cx+=chra;}   
   cx+=2*chra;win.drawString(cx,cy,String(Clock.getYear()+2000));

   cy=3*line+5;cx=cleft+20;
   if(Clock.getHour(h12,PM)<10) {win.drawString(cx,cy,"0");cx+=chra;}
   win.drawString(cx,cy,String(Clock.getHour(h12,PM)));
   if(Clock.getHour(h12,PM)>9) {cx+=chra;}
   cx+=chra;win.drawString(cx,cy,":");
   if(Clock.getMinute()<10) {cx+=chra;win.drawString(cx,cy,"0");}
   cx+=chra;win.drawString(cx,cy,String(Clock.getMinute()));
   if(Clock.getMinute()>9) {cx+=chra;}
   cx+=chra;win.drawString(cx,cy,":");
   if(Clock.getSecond()<10) {cx+=chra;win.drawString(cx,cy,"0");}
   cx+=chra;win.drawString(cx,cy,String(Clock.getSecond()));

   //win.display();
}

Just for understanding this strange project is a special clock unique in the world which you can find in the city of Berlin.

I know that NANO works with 5V and ESP with 3.3V
I know that these Matrix displays work with 5V powersupply and 5V logic signal level
I know that these Matrix displays need to be powered externally with a strong powersupply (I am using a 5V 3A powersupply but these displays are pretty small and on the NANO it works with a simple 2A cellphone charger)
I know that the GND of processor and matrix devices need to be connected together
I am also using a levelshifter for the SPA signals. Actually with or without levelshifter there is the same issue.

Somebody has an idea what this strange issue is about ?

xfpd · June 25, 2024, 8:12pm

Your compiler does not mind the re-definition of Nano pinMin and pinHour?

galacticobmg · June 25, 2024, 8:16pm

pinMin and pinHour are the Chipselectlines for the two separated Matrixdisplays for Minutes and Hours. I don´t see where they are defined more than once.

xfpd · June 25, 2024, 8:21pm

You have been staring at your code too long. Enjoy a bicycle ride.

galacticobmg · June 25, 2024, 9:12pm

Ohh yes you are right, the #define Block is from some tests with the display and accidently keeps in the program. But the compiler does not care

system · December 22, 2024, 9:12pm

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Matrix7219 displays scrambled display on ESP32C mini

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