sketch

#include <LiquidCrystal.h>

LiquidCrystal lcd(2, 3, 4, 6, 7, 8, 9);

char inByte = 0;

void setup() {

  pinMode(5, INPUT);  // This is the frequency input
  pinMode(10, OUTPUT);  // Backlight control pin
  digitalWrite(10, HIGH);  // Turn backlight on
  lcd.begin(16, 2);
  Serial.begin(115200);
  // Print a splash screen to the LCD.
  lcd.print("Serial Display");
  lcd.setCursor(1, 3);
  lcd.print("By Dmitry");
  delay(2000);
  lcd.clear();
  lcd.print("Ready to ");
  lcd.setCursor(1, 3);
  lcd.print("accept data");

}

void loop() {

  if(Serial.available() > 0)
  {
    inByte = Serial.read();
    if(inByte == '-')   //type "-" symbol to erase the lcd
    {
      lcd.clear();
    }
    else if(inByte == '=')  //"=" symbol is equivalent to "Enter"
    {
      lcd.setCursor(0, 1);
    }
    else
    {
      lcd.print(inByte);
    }
  }

}