View source for WeMOS: D1 R1 mini LCD I2C PCF8574 Hello World

 // This example shows various featues of the library for LCD with 16 chars and 2 lines.
 // Library https://github.com/mathertel/LiquidCrystal_PCF8574
 
 #include <Arduino.h>
 #include <Wire.h>
 #include <LiquidCrystal_PCF8574.h>
 
 LiquidCrystal_PCF8574 lcd(0x27);  // set the LCD address to 0x27 for a 16 chars and 2 line display
 
 void setup() {
   Serial.begin(115200);
   Wire.begin();
   Wire.beginTransmission(0x27);
   lcd.begin(16, 2);  // initialize the lcd
 }
 
 void loop() {
   lcd.setBacklight(255);
   lcd.home();
   lcd.clear();
   lcd.noBlink();
   lcd.noCursor();
   lcd.setCursor(0,1);
   lcd.print("Hello World!");
   delay(3000);
 }