How to display custom animations on 16x2 LCD using 8051 microcontroller (AT89C51)- (Part 12/45)

Animating custom made characters on a 16x2 LCD screen can be very exciting. (Also see LCD custom characters.) This topic explains the principle and operation of a displaying animation on LCD using Microcontroller AT89C51.

There’s a useful side effect to the way the LCD controller uses CG RAM. Normally, we define a pattern in CG RAM, and then print the character. But it is also possible to change the CG RAM for characters that are already on the screen, and their appearance will change (for more detail about CG RAM and LCD refer LCD custom character and LCD interfacing).

The connections in the circuit are as follow: the output of controller (from port P₂) goes to data pins of LCD numbered 7-14. The control pins RS (pin4), R/W (pin5) and EN (pin6) are connected to the pins 0, 1 and 6 of port P₃ (P₃^0, P₃^1 & P₃^6, respectively).

Sample animation: A moving arrow continuously passing through hearts.

Before animation, the custom characters of heart, cutting heart, blank screen and arrow should be stored at different addresses. For more detail on creating custom characters refer LCD custom character.

In 1^st step print an arrow and two hearts placed at some distance apart.

In 2^nd step print blank screen, cutting heart and 2^nd heart.

In 3^rd step print blank screen, heart, arrow and 2^nd heart.

In 4^th step print blank screen, heart, blank screen, arrow and 2^nd heart.

In 5^th step print blank screen, heart, blank screen, blank screen and

cutting heart.

These steps can be repeated continuously to produce an animation.

Project Source Code

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// Program to make an animation using custom characters

#include<reg51.h>
sfr lcd_data_pin=0xA0;
sbit rs=P3^0;  //Register select (RS) pin
sbit rw=P3^1;  // Read write (RW) pin
sbit en=P3^6;  //Enable (EN) pin

void delay(unsigned int count)  // Function to provide time delay in msec.
{
int i,j;
for(i=0;i<count;i++)
for(j=0;j<1275;j++);
}

void lcd_command(unsigned char comm)  //Function to send command to LCD.
{
lcd_data_pin=comm;
en=1;
rs=0;
rw=0;
delay(1);
en=0;
}           

void lcd_data(unsigned char disp)  //Function to send data to LCD.
{
lcd_data_pin=disp;
en=1;
rs=1;
rw=0;
delay(1);
en=0;
}

void lcd_ini()  //Function to initialize the LCD
{
lcd_command(0x38); 
delay(200);
lcd_command(0x0F); 
delay(200);
 
}

void character()
{
while(1)
{
  char k,position;
  k=0;          
  position=0x7F;
  lcd_command(64);  //Address where character heart is to be stored
  lcd_data(0);
  lcd_data(10);
  lcd_data(21);
  lcd_data(17);
  lcd_data(10);
  lcd_data(4);
  lcd_data(0);
  lcd_data(0);
  lcd_command(0x81); 
  lcd_data(0);  
  delay(5);

  lcd_command(64); 
  lcd_command(0x84);
  lcd_data(0);
  delay(5);

  lcd_command(80);  //Address where character arrow is stored
  lcd_data(0);
  lcd_data(4);
  lcd_data(2);
  lcd_data(31);
  lcd_data(2);
  lcd_data(4);
  lcd_data(0);
  lcd_data(0);
  lcd_command(0x80);
  lcd_data(2);
  delay(5);

  lcd_command(72);  // Address where blank character is to be stored
  lcd_data(0);
  lcd_data(0);
  lcd_data(0);
  lcd_data(0);
  lcd_data(0);
  lcd_data(0);
  lcd_data(0);
  lcd_data(0);
  lcd_command(0x80);
  lcd_data(1);
  delay(5);

  lcd_command(88);  // Address where Arrow heart character is to be stored
  lcd_data(0);
  lcd_data(10);
  lcd_data(21);
  lcd_data(31);
  lcd_data(10);
  lcd_data(4);
  lcd_data(0);
  lcd_data(0);
  lcd_command(0x81);
  lcd_data(3);
  delay(5);

  lcd_command(72); 
  lcd_command(80);
  lcd_data(1);
  delay(5);

  lcd_command(64); 
  lcd_command(0x81);
  lcd_data(0);
  delay(5);

  lcd_command(80); 
  lcd_command(0x82);
  lcd_data(2);
  delay(5);  

  lcd_command(72); 
  lcd_command(0x80);
  lcd_data(1);
  delay(5);

  lcd_command(64); 
  lcd_command(0x81);
  lcd_data(0);
  delay(5);

  lcd_command(72); 
  lcd_command(0x82);
  lcd_data(1);
  delay(5);

  lcd_command(80); 
  lcd_command(0x83);
  lcd_data(2);
  delay(5);  

  lcd_command(72); 
  lcd_command(0x80);
  lcd_data(1);
  delay(5);

  lcd_command(64); 
  lcd_command(0x81);
  lcd_data(0);
  delay(5);

  lcd_command(72); 
  lcd_command(0x82);
  lcd_data(1);
  delay(5);

  lcd_command(72); 
  lcd_command(0x83);
  lcd_data(1);
  delay(5);

  lcd_command(64); 
  lcd_command(0x84);
  lcd_data(0);
  delay(5);     

  lcd_command(72); 
  lcd_command(0x80);
  lcd_data(1);
  delay(5);

  lcd_command(64); 
  lcd_command(0x81);
  lcd_data(0);
  delay(5);

  lcd_command(72); 
  lcd_command(0x82);
  lcd_data(1);
  delay(5);

  lcd_command(72); 
  lcd_command(0x83);
  lcd_data(1);
  delay(5);

  lcd_command(88); 
  lcd_command(0x84);
  lcd_data(3);
  delay(5);

}
}

void main()
{
lcd_ini();
character();
}

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