What is a LCD. It is a Liquid Crystal display. It is a basic module which is used in many electronics projects. It is used to display characters. You can display a number of characters like numbers 0 to 9 alphabets a to z and special characters such as !,@,#. Here 16x2 means it can display 16 characters in one line and there are two such lines. That means you can display 32 characters at a time. Each character is displayed using a 8 by 5 matrix. We can display our own custom character on LCD by passing the corresponding data.
A 16x2 LCD contains 16 pins. Out of 16, 8 pins are data pins whereas 3 pins are there to control the operation of LCD. Pin no. 7 to 14 are used to provide the 8 bit data to LCD.
There are 3 control pins. One is register select (pin no. 4).When it is 0 it selects command register and when the pin is high it selects data register. There are two types of registers in LCD. One is command register which stores the information about how to perform various operations of LCD. The other register is data register. It stores the ASCII value of the data which is to be displayed.
Second control pin is Pin no. 5 which is used for read and write operations. When it is 0 it perform write to register operation and when it is 1 it perform read from register operation.
Third control pin is Enable pin (pin no. 6). When a high to low pulse is provided to this pin then the data is sent to data pins.
Pin no. 1 and 2 are GND and VCC respectively. We should give the 5V supply to this two pins. One more thing which we can do with LCD is backlight brightness adjustment. The supply for backlight is given at pin no. 15 and 16. Whereas we can control the brightness of the LCD by controlling the voltage given to the pin no.3. Less voltage means less brightness. For adjusting the voltage generally a potentiometer is connected to the pin no.3.
Pin Description
