Using Mega with SD card and (2) I2C LCD 4x20 displays

Projects Programming
1

Greetings Ladies and Gents.
I have jambed myself up trying to get this to work. I have an SD card that had 30 somthing .TXT files on it that I am going to read from the SD card and print on to one of two LCD screens. I have been able to read the files from the SD card and print them to the serial monitor. I have been able to lcd.print(" "); to both of the lcd displays elsewhere in the code and they work so I know that my hardware is correct. I placed a lcd1.print(dataFile); right below the Serial.write(dataFile.read()); and i get gibberish on the LCD screen. I tried a lcd1.print(dataFile.read()); in the same spot and I got a rapidly changing series of numbers and letters in the first two segments and then it stopped on 31. What the colorful cussword is going on here? >:( What am I missing. Ive been banging my head on the desk so long I have a flat spot. Is there a way for me to read the SD card file into a variable and then print to the LCD screens from that variable. If so what would that variable be and how would I set it up? An array? A string? Ive read so much that I have information overload and I am not sure what to use where. Your kindly patient assistance would be most welcome. (code attached)
Amachinetech

#include <SPI.h>
#include <SD.h>
#include <Wire.h>
#include <LiquidCrystal_I2C.h>
LiquidCrystal_I2C lcd1(0x26, 20, 4);//change the address, width and height here to match the LCD screen you are using.
LiquidCrystal_I2C lcd2(0x27, 20, 4);//change the address, width and height here to match the LCD screen you are using.

const int chipSelect = 4;

void setup() {
    lcd1.begin();
    lcd2.begin();
    
  // Open serial communications and wait for port to open:
  Serial.begin(9600);
  lcd1.print("starting up"); //<----these print to the LCD screens just fine
  lcd2.print("me too");
  
  while (!Serial) {
    ; // wait for serial port to connect. Needed for native USB port only
  }


  Serial.print("Initializing SD card...");

  // see if the card is present and can be initialized:
  if (!SD.begin(chipSelect)) {
    Serial.println("Card failed, or not present");
    // don't do anything more:
    while (1);
  }
  Serial.println("card initialized."); //<--card initializes correctly and I can read all of the files. 

  // open the file. note that only one file can be open at a time,
  // so you have to close this one before opening another.
  File dataFile = SD.open("001.txt");

  // if the file is available, write to it:
  if (dataFile) {
    while (dataFile.available()) {
    Serial.write(dataFile.read()); //<------if either one of the below is present then I get giberish on the serial monitor
    //lcd1.print(dataFile);  <-------this doesn't work, just prints a two digit number on the screen
    //lcd1.print(dataFile.read()); <-----this displays a stream of 1s over most of the LCD screen
    }
    dataFile.close();
  }

  
  // if the file isn't open, pop up an error:
  else {
    Serial.println("error opening datalog.txt");
  }
}

void loop() {
}
2

What the colorful cussword is going on here?

Printing a file does not make sense, so lcd1.print(dataFile) is a silly thing to do.

Printing a character does make sense, so "lcd1.print(dataFile.read()); in the same spot and I got a rapidly changing series of numbers and letters in the first two segments" makes perfect sense.

and then it stopped on 31.

I really have no idea what this means. In this phrase, it is a pronoun with no referent, so it is not at all clear what stopped or what the relevance of the 31 is.

The read() method returns an int, so that the high order byte can be set to indicate an error. Printing an int and printing a character result in quite different output. The proper way to read and print, on the serial port and on the LCD, every character from the file is:

    while (dataFile.available())
    {
       char c = dataFile.read();
       Serial.print(c);
       lcd1.print(c);
    }