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Here's a bit of code to do some simple scrolling.

 

 
char buf[16] = "";
int point = 0;
int pos = 0;

String str = "  HELLO THIS SEEMS TO WORK AND SCROLL OK !!   ";
 
const byte _A0 = 13;
const byte _A1 = 4;
const byte _A2 = 33;
const byte _A3 = 25;
const byte _D0 = 17;
const byte _D1 = 27;
const byte _D2 = 26;
const byte _D3 = 21;
const byte _D4 = 22;
const byte _D5 = 19;
const byte _D6 = 18;
const byte _WR = 16;
const byte _BL = 23;
const byte _CLR = 32;
 
 
void setup() {
   
  Serial.begin(115200);
 
  pinMode(_A0, OUTPUT);
  pinMode(_A1, OUTPUT);
  pinMode(_A2, OUTPUT);
  pinMode(_A3, OUTPUT);
  pinMode(_D0, OUTPUT);
  pinMode(_D1, OUTPUT);
  pinMode(_D2, OUTPUT);
  pinMode(_D3, OUTPUT);
  pinMode(_D4, OUTPUT);
  pinMode(_D5, OUTPUT);
  pinMode(_D6, OUTPUT);
  pinMode(_WR, OUTPUT);
  pinMode(_BL, OUTPUT);
  pinMode(_CLR, OUTPUT);
 
  digitalWrite(_BL, HIGH); 
  digitalWrite(_CLR, LOW);
 
  delay(20);
  digitalWrite(_CLR, HIGH);
  delay(20);
  digitalWrite(_WR, HIGH);
  delay(20);
 
}


unsigned long intervalPreviousMillis = 0;
const long interval = 300;

 
void loop() {
 
  unsigned long currentMillis = millis();
 
  if ((currentMillis - intervalPreviousMillis) >= interval) {
 
    intervalPreviousMillis = currentMillis;
 
    char  x;
 
    for (int i = 0;i < 16; i++){
      if (point + i >= str.length()){
        x = str[(point + i) - str.length()];
      } else {
        x = str[point + i];
      }
 
      switch(i){
        // display 1
        case 0:
          displayChar(x, 3, 0);
          break;
        case 1:
          displayChar(x, 2, 0);
          break;
        case 2:
          displayChar(x, 1, 0);
          break;
        case 3:
          displayChar(x, 0, 0);
          break;
        // display 2
        case 4:
          displayChar(x, 3, 1);
          break;
        case 5:
          displayChar(x, 2, 1);
          break;
        case 6:
          displayChar(x, 1, 1);
          break;
        case 7:
          displayChar(x, 0, 1);
          break;
         // display 3
        case 8:
          displayChar(x, 3, 2);
          break;
        case 9:
          displayChar(x, 2, 2);
          break;
        case 10:
          displayChar(x, 1, 2);
          break;
        case 11:
          displayChar(x, 0, 2);
          break;
        // display 4
        case 12:
          displayChar(x, 3, 3);
          break;
        case 13:
          displayChar(x, 2, 3);
          break;
        case 14:
          displayChar(x, 1, 3);
          break;
        case 15:
          displayChar(x, 0, 3);
          break;
 
      }
     
    }
 
    point++;
    if (point >= str.length()){
      point = 0;
    }
 
  }
  
}



void displayChar(char myChar, int myPos, byte myDisp){
 
  switch (myDisp){
    case 0:
      digitalWrite(_A2, HIGH);
      digitalWrite(_A3, HIGH);
      break;
    case 1:
      digitalWrite(_A2, LOW);
      digitalWrite(_A3, HIGH);
      break; 
    case 2:
      digitalWrite(_A2, HIGH);
      digitalWrite(_A3, LOW);
      break;
    case 3:
      digitalWrite(_A2, LOW);
      digitalWrite(_A3, LOW);
      break;
  }
 
  switch (myPos){
    case 0:
      digitalWrite(_A0, LOW);
      digitalWrite(_A1, LOW);
      break;
    case 1:
      digitalWrite(_A0, HIGH);
      digitalWrite(_A1, LOW);
      break;
    case 2:
      digitalWrite(_A0, LOW);
      digitalWrite(_A1, HIGH);
      break;
    case 3:
      digitalWrite(_A0, HIGH);
      digitalWrite(_A1, HIGH);
      break;
  }

  digitalWrite(_D0, (myChar >> 0) & 1);
  digitalWrite(_D1, (myChar >> 1) & 1);
  digitalWrite(_D2, (myChar >> 2) & 1);
  digitalWrite(_D3, (myChar >> 3) & 1);
  digitalWrite(_D4, (myChar >> 4) & 1);
  digitalWrite(_D5, (myChar >> 5) & 1);
  digitalWrite(_D6, (myChar >> 6) & 1);
  
  digitalWrite(_WR, LOW);
  digitalWrite(_WR, HIGH);
 
}

 

 

 

 

 

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