This is a simple example of a LCD 16 character 2 line (1602) shield that mounts directly on an Uno or Mega.
This also has an addition benefit of 5 built in buttons with built in series resistors that all use the A0 input.
The buttons use a series of resistors that act as voltage dividers giving each button a unique voltage.
Since resistors do vary, you will need to run the program (Keys_1602shield) to set the voltage ranges.
In serial monitor, you will see the key and the bit integer value.
Write down these values.
In the program, set the break values between these measurements.
NOTE: this LCD shield wiring differs from some LCDs with the code:
LiquidCrystal lcd(8, 9, 4, 5, 6, 7);
Then run the LCD_KS_Menu program for a simple menu example.
Use the UP/Down to scroll the menu items.
Use the RIGHT button to set the Digital ouput.
Use the LEFT button to return to the menu and turn the output off.