LCD is also used almost in every Engineering Project for displaying different values. For example, if you have used the ATM machine, which you must have, then you have seen an LCD there displaying the options to select. Obviously that's quite a big LCD but still LCD. Similarly, all mobile phones are also equipped with LCDs. The LCD we are gonna use in this project is quite small and basic. It is normally known as the 16x2 LCD as it has rows and 2 columns for writing purposes. So, we are gonna interface that LCD with 8051 Microcontroller. The proteus Simulation along with hex file and the programming code in keil uvision 3 is given at the end of this post for download. If you are working with Arduino, then you should have a look at Interfacing of LCD with Arduino. The next level from LCD is Graphical LCD also known as GLCD, so if you wanna know more about that then you should read Interfacing of Arduino with GLCD. So, let's get started with it.
void lcdinit(void)
{
delay(15000);
writecmd(0x30);
delay(4500);
writecmd(0x30);
delay(300);
writecmd(0x30);
delay(650);
writecmd(0x38); //function set
writecmd(0x0c); //display on,cursor off,blink off
writecmd(0x01); //clear display
writecmd(0x06); //entry mode, set increment
}
void writecmd(int z)
{
RS = 0; // => RS = 0
P2 = z; //Data transfer
E = 1; // => E = 1
delay(150);
E = 0; // => E = 0
delay(150);
}
void writedata(char t)
{
RS = 1; // => RS = 1
P2 = t; //Data transfer
E = 1; // => E = 1
delay(150);
E = 0; // => E = 0
delay(150);
}
#include<reg51.h>
//Function declarations
void cct_init(void);
void delay(int);
void lcdinit(void);
void writecmd(int);
void writedata(char);
void ReturnHome(void);
//*******************
//Pin description
/*
P2 is data bus
P1.0 is RS
P1.1 is E
*/
//********************
// Defines Pins
sbit RS = P1^0;
sbit E = P1^1;
// ***********************************************************
// Main program
//
void main(void)
{
cct_init(); //Make all ports zero
lcdinit(); //Initilize LCD
writecmd(0x81);
writedata('w'); //write
writedata('w'); //write
writedata('w'); //write
writedata('.'); //write
writedata('T'); //write
writedata('h'); //write
writedata('e'); //write
writedata('E'); //write
writedata('n'); //write
writedata('g'); //write
writedata('i'); //write
writedata('n'); //write
writedata('e'); //write
writedata('e'); //write
writedata('r'); //write
writedata('i'); //write
writedata('n'); //write
writedata('g'); //write
writecmd(0xc4);
writedata('P'); //write
writedata('r'); //write
writedata('o'); //write
writedata('j'); //write
writedata('e'); //write
writedata('c'); //write
writedata('t'); //write
writedata('s'); //write
writedata('.'); //write
writedata('c'); //write
writedata('o'); //write
writedata('m'); //write
ReturnHome(); //Return to 0 position
while(1)
{
}
}
void cct_init(void)
{
P0 = 0x00; //not used
P1 = 0x00; //not used
P2 = 0x00; //used as data port
P3 = 0x00; //used for generating E and RS
}
void delay(int a)
{
int i;
for(i=0;i<a;i++); //null statement
}
void writedata(char t)
{
RS = 1; // => RS = 1
P2 = t; //Data transfer
E = 1; // => E = 1
delay(150);
E = 0; // => E = 0
delay(150);
}
void writecmd(int z)
{
RS = 0; // => RS = 0
P2 = z; //Data transfer
E = 1; // => E = 1
delay(150);
E = 0; // => E = 0
delay(150);
}
void lcdinit(void)
{
delay(15000);
writecmd(0x30);
delay(4500);
writecmd(0x30);
delay(300);
writecmd(0x30);
delay(650);
writecmd(0x38); //function set
writecmd(0x0c); //display on,cursor off,blink off
writecmd(0x01); //clear display
writecmd(0x06); //entry mode, set increment
}
void ReturnHome(void) //Return to 0 location
{
writecmd(0x02);
delay(1500);
}
Download Proteus Simulation & Code
That's all for today, in the next post I am gonna share how to display custom characters on LCD with 8051 Microcontroller, because till now you can just display the simple characters like alphabets and numbers on it but can't display the custom characters like arrowhead etc. You should have a look at LCD Interfacing with Microcontrollers, where I have combined all tutorials related to LCD. So stay tuned and have fun.