Scrolling Text on MAX7219

Hello falks,

I have a code below that works fine. The code you see, works like this:

  1. You have to open the Serial Monitor
  2. Type in your text which has to be scrolled
  3. Click onto "Enter"

Now your text should be scrolled on a LED Matrix (8 devices)

My Problem is:

I do not need the Serial Monitor. I wana define my scrolling text via String, like this:

String MyText = "Here is my scrolling text";

So, how could I achieve this ? I want to define my text spontantiosly via String, instead of typing it on the serial monitor. Here is the code:

#include <MD_Parola.h>
#include <MD_MAX72xx.h>
#include <SPI.h>

// set to 1 if we are implementing the user interface pot, switch, etc
#define USE_UI_CONTROL 0

#if USE_UI_CONTROL
#include <MD_UISwitch.h>
#endif

// Turn on debug statements to the serial output
#define DEBUG 0

#if DEBUG
#define PRINT(s, x) { Serial.print(F(s)); Serial.print(x); }
#define PRINTS(x) Serial.print(F(x))
#define PRINTX(x) Serial.println(x, HEX)
#else
#define PRINT(s, x)
#define PRINTS(x)
#define PRINTX(x)
#endif

// Define the number of devices we have in the chain and the hardware interface
// NOTE: These pin numbers will probably not work with your hardware and may
// need to be adapted
#define HARDWARE_TYPE MD_MAX72XX::FC16_HW
#define MAX_DEVICES 8
#define CLK_PIN   14 // d6
#define CS_PIN    15 // d8
#define DATA_PIN  13 // d7

// HARDWARE SPI
MD_Parola P = MD_Parola(HARDWARE_TYPE, CS_PIN, MAX_DEVICES);
// SOFTWARE SPI
//MD_Parola P = MD_Parola(HARDWARE_TYPE, DATA_PIN, CLK_PIN, CS_PIN, MAX_DEVICES);

// Scrolling parameters
#if USE_UI_CONTROL
const uint8_t SPEED_IN = A5;
const uint8_t DIRECTION_SET = 8;  // change the effect
const uint8_t INVERT_SET = 9;     // change the invert

const uint8_t SPEED_DEADBAND = 5;
#endif // USE_UI_CONTROL

uint8_t scrollSpeed = 25;    // default frame delay value
textEffect_t scrollEffect = PA_SCROLL_LEFT;
textPosition_t scrollAlign = PA_LEFT;
uint16_t scrollPause = 2000; // in milliseconds

// Global message buffers shared by Serial and Scrolling functions
#define	BUF_SIZE	75
char curMessage[BUF_SIZE] = { "" };
char newMessage[BUF_SIZE] = { "Click on any button on your screen!" };
bool newMessageAvailable = true;

#if USE_UI_CONTROL

MD_UISwitch_Digital uiDirection(DIRECTION_SET);
MD_UISwitch_Digital uiInvert(INVERT_SET);






void doUI(void)
{
  // set the speed if it has changed
  {
    int16_t speed = map(analogRead(SPEED_IN), 0, 1023, 10, 150);

    if ((speed >= ((int16_t)P.getSpeed() + SPEED_DEADBAND)) ||
      (speed <= ((int16_t)P.getSpeed() - SPEED_DEADBAND)))
    {
      P.setSpeed(speed);
      scrollSpeed = speed;
      PRINT("\nChanged speed to ", P.getSpeed());
    }
  }

  if (uiDirection.read() == MD_UISwitch::KEY_PRESS) // SCROLL DIRECTION
  {
    PRINTS("\nChanging scroll direction");
    scrollEffect = (scrollEffect == PA_SCROLL_LEFT ? PA_SCROLL_RIGHT : PA_SCROLL_LEFT);
    P.setTextEffect(scrollEffect, scrollEffect);
    P.displayClear();
    P.displayReset();
  }

  if (uiInvert.read() == MD_UISwitch::KEY_PRESS)  // INVERT MODE
  {
    PRINTS("\nChanging invert mode");
    P.setInvert(!P.getInvert());
  }
}
#endif // USE_UI_CONTROL









void readSerial(void)
{
  static char *cp = newMessage;

  while (Serial.available())
  {
    *cp = (char)Serial.read();
    if ((*cp == '\n') || (cp - newMessage >= BUF_SIZE-2)) // end of message character or full buffer
    {
      *cp = '\0'; // end the string
      // restart the index for next filling spree and flag we have a message waiting
      cp = newMessage;
      newMessageAvailable = true;
    }
    else  // move char pointer to next position
      cp++;
  }
}





void setup()
{
  Serial.begin(115200);
  Serial.print("\n[Parola Scrolling Display]\nType a message for the scrolling display\nEnd message line with a newline");

#if USE_UI_CONTROL
  uiDirection.begin();
  uiInvert.begin();
  pinMode(SPEED_IN, INPUT);

  doUI();
#endif // USE_UI_CONTROL

  P.begin();
  P.displayText(curMessage, scrollAlign, scrollSpeed, scrollPause, scrollEffect, scrollEffect);
}






void loop()
{
#if USE_UI_CONTROL
  doUI();
#endif // USE_UI_CONTROL
  
  if (P.displayAnimate())
  {
    if (newMessageAvailable)
    {
      strcpy(curMessage, newMessage);
      newMessageAvailable = false;
    }
    P.displayReset();
  }
  readSerial();
}

sss

I wrote this code years ago to print spontanious message in Max7219.

#include  <HCMAX7219.h>
#include "SPI.h"
/* Set the LOAD (CS) digital pin number*/
#define LOAD 10
/* Create an instance of the library */
HCMAX7219 HCMAX7219(LOAD);
void setup()
{
}
/* Main program */
void loop()
{
byte Loopcounter;
int Position;
/* Clear the output buffer */
HCMAX7219.Clear();
/* SCROLL All TEXT 2 TIMES */
HCMAX7219.Invert(INVERTON);
for(Position=0; Position <= 600; Position++)
{
HCMAX7219.printMatrix("Mod edit: Text replaced with something that doesn't look like advertising.", Position);
HCMAX7219.Refresh();
delayMicroseconds(100);
}
HCMAX7219.Invert(INVERTOFF);
for(Position=0; Position <= 1050; Position++)
{
HCMAX7219.printMatrix("Mod edit: Text replaced with something that doesn't look like advertising.", Position);
HCMAX7219.Refresh();
delayMicroseconds(100);
}
for(Position=0; Position <= 1050; Position++)
{
HCMAX7219.printMatrix("Mod edit: Text replaced with something that doesn't look like advertising.", Position);
HCMAX7219.Refresh();
delayMicroseconds(100);
}
}
const char myArray[] = {"Here is my text"};

void setup() {
  Serial.begin(115200);
  Serial.println(myArray);
}

void loop(){}

@liaifat85 - Format your code.

Thanks falks for your replies. I just solved the problem with a second IC. Here is the solution:

There are two ESP8266 which communicates between each other. The first ESP display any incoming Serial on the LED-Matrix, so it works as a receiver. The second ESP is sending the code trough a local website (192.168.4.1), so it works as a sender. I have to open the local webpage, and type in any Word into a html-input-field. After clicking the "Send" Button, than the sender-ESP makes a Serial.println("Any Word"). Than, my word is landing on the first receiver-ESP. And here we go, the code is displayed on the LED-Matrix.

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