LCD interfacing with Atmega 32/16 - 4 wire connection

Last time we have given example how to connect LCD with controller as you can see Our Post Interfacing LCD with At mega 16/32.

Now i am introducing concept of four wire data transmission.This way you will be able to save controller pin for another applications.

In above diagram you will see we are using 4 pin of PORTA for data transmission and another 3 pins of same PORT for control lines.In this way we are able to save pins and schematic drawing becomes much more easier.

Anyone who is using ADC for sensors should use other PORTB,C,D rather than PORTA(with same configuration).

Also Read LCD Complete Tutorials for beginners

As earlier as i have said, whenever you are changing your hardware,you have to make changes in your programming.I will be posting programs for this new setup in coming days.

Tutorial-LCD (Liquid Crystal Display 16X2):-
Its 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.

The command register stores the command instructions given to the LCD. A command is an instruction given to LCD to do a predefined task like initializing it, clearing its screen, setting the cursor position, controlling display etc. The data register stores the data to be displayed on the LCD. The data is the ASCII value of the character to be displayed on the LCD.

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