ESP32: Print a String on a 16×2 LCD

ESP32: Print a String on a 16×2 LCD | Embed Club

// esp32Lcd.ino - "Hello" on a 16x2 character LCD, wired in 4-bit mode.
#include <LiquidCrystal.h>

// LiquidCrystal(rs, enable, d4, d5, d6, d7)
//
// Plain GPIO numbers. The ESP32 has no D1/D2/D4... labels - those are
// NodeMCU/ESP8266 silkscreen names, and pasting them here will not compile.
const int RS = 13, EN = 14, D4 = 27, D5 = 26, D6 = 25, D7 = 33;

LiquidCrystal lcd(RS, EN, D4, D5, D6, D7);

void setup() {
  lcd.begin(16, 2);          // 16 columns, 2 rows
  lcd.clear();

  lcd.setCursor(0, 0);       // column 0, row 0
  lcd.print("Hello!");

  lcd.setCursor(0, 1);       // row 1 is the SECOND row - rows count from 0
  lcd.print("Embed Club");
}

void loop() {
  // Nothing here. The text is already on the screen and the LCD holds it
  // without being refreshed.
}

// esp32LcdI2c.ino - same output, two wires instead of six.
// Needs a PCF8574 "backpack" soldered to the LCD, and the
// LiquidCrystal_I2C library from the Library Manager.
#include <Wire.h>
#include <LiquidCrystal_I2C.h>

// 0x27 is the usual address; some backpacks are 0x3F. Run an I2C scanner
// sketch if nothing appears.
LiquidCrystal_I2C lcd(0x27, 16, 2);

void setup() {
  Wire.begin(21, 22);        // ESP32 default SDA, SCL
  lcd.init();
  lcd.backlight();

  lcd.setCursor(0, 0);
  lcd.print("Hello!");
  lcd.setCursor(0, 1);
  lcd.print("Embed Club");
}

void loop() {}

ESP32: Print a String on a 16×2 LCD

ESP32: Print a String on a 16×2 LCD

What You Need

Get Arduino IDE

Wiring

The 3.3V Problem

The Code

Two Wires Instead of Six

If It Does Not Work