LCD (Liquid Crystal Display) screen is an electronic display module and find a wide range of applications. A 16x2 LCD display is very basic module and is very commonly used in various devices and circuits. These modules are preferred over seven segments and other multi segment LEDs. The reasons being: LCDs are economical; easily programmable; have no limitation of displaying special & even custom characters (unlike in seven segments), animations and so on.
A 16x2 LCD means it can display 16 characters per line and there are 2 such lines. In this LCD each character is displayed in 5x7 pixel matrix. This LCD has two registers, namely, Command and Data.
Supply voltage; 5V (4.7V – 5.3V)
Contrast adjustment; through a variable resistor
Selects command register when low; and data register when high
Low to write to the register; High to read from the register
Sends data to data pins when a high to low pulse is given
8-bit data pins
Backlight VCC (5V)
Backlight Ground (0V)