Alpha Numeric 16x2 LCD

It is a rectangular LCD panel that can show 16 alphanumeric characters in one line and there are 2 such lines. Hence it is named 16X2 LCD. It has 16 pins. The figure below shows a 16X2 LCD with respective pins.

FEATURES

• 5 x 8 dots with cursor
• The built-in controller (KS 0066 or Equivalent)
• + 5V power supply (Also available for + 3V)
• 1/16 duty cycle
• B/L to be driven by pin 1, pin 2 or pin 15, pin 16, or A.K (LED)
• N.V. optional for + 3V power supply

PIN Description

• GND- Ground(0 volt)
•  Vcc-    Digital supply voltage(5 volt)
•  VEE-   Contrast adjustment through a variable resistor
•  RS- Register Select. It selects the command register when low(0-volt logic) and selects the data register when high(5 v logic).

• R/W- Read / Write. It is set low to Write to MCU and high to Read from MCU.
• D0 to D7 are the data pins. It does not matter which port you connect to.
• Led+(A) and Led-(K) – are the backlight of the LCD with 5 volts and 0 volts respectively.

      How does an Alpha Numeric 16X2 LCD works?

1.    At first we initialize the LCD by selecting command registers and passing the corresponding command instructions.

2.    At 2^nd select data registers and pass corresponding data values to be shown in the display.

RS, RW, and EN are the command registers, and  D0 to D7 are the data registers.

Following are some command instructions that we frequently use in programs:

0x38 - This command instruction tells the LCD to select 8-bit

            data,2 lines, 5x7 pixels of text size

0x01 - clears display after every character

0x80 - Shifts the entire display to the top  right-hand side

0xC0 - Goes to the 2^nd line etc.

Common Circuit Design