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Counting the number of times pressed of Switch , C program in MPLAB X

In this program we are going to count the number of times a switch pressed,and displaying it on a LCD .. and each time the switch pressed a LED will lighted up.




First create a new project and add a c main file like in the  steps for  Blinking a LED using MPLAB X , PIC16F877A

Components 


1. PIC16F877A micro controller
2. animated LED  
3. A toggle switch
4.16x2 LCD display




Steps in the program

1. define the ports for easy usage 

Defines the control pins of LCD to the 0th,1st and 2nd pin of PORT D
    #define RS RD0
    #define RW RD1
   #define EN RD2
Defines the data port of the  LCD to PORT B
   #define DATA PORTC
Defines switch in the 0th pin of PORT C
   #define S RC0
Defines LED on the 3rd pin of PORT D
   #define L RD3
2. Function declarations .. here we declare 3 functions  and all the 3 functions is for LCD

void LCD_CMD(unsigned int value); //This function is pass the LCD commands
void LCD_DAT(unsigned int value); // this is for pass the DATA to the LCD which is to displayed 
void LCD_INIT(); //this to initialize the LCD
void delay(); // this is to delay the LCD commands 


3. next is main function .. in main function we make 
  •  PORT C as input where we have connected the switch
  •  PORT D as output where we have connected the LED and control pins of LCD
  • PORT B as outout where we have connected DATA pins of LCD
    TRISC  =0x0F;
    TRISD  =0x00;
    TRISB = 0x00;

4. The function LCD_INIT(); is called for initializing the LCD
5. Declared a variable called count, and initialized it to zero
   int count;
   count=0;
6.  we put the LED off 
7. now we are going for a infinite loop by 
    while(1)
    { 
     }
8. In the loop we are checking switch is ON or OFF condition
 if the switch is ON ; LED is on and count is incremented by 1 and display the value of count in LCD 

if the Switch is OFF it wait for the condition when the Switch is ON 

schematic diagram 



full Program
 ###################################################################################
    /*
 * File:   switchcount.c
 * Author: Ebin Ephrem
 
 */

#include<htc.h>
__CONFIG(0x193A);

C
#define RS RD0
#define RW RD1
#define EN RD2
#define DATA PORTB
#define S RC0
#define L RD3

void LCD_CMD(unsigned int value);
void LCD_DAT(unsigned int value);
void LCD_INIT();
void delay();



void main(void)
{
    TRISC  =0x0F;
    TRISD  =0x00;
    TRISB = 0x00;
LCD_INIT();
int count;
count=0;
L=0;

  while(1)
  {
if( S == 1)
       {
    while(S==1);
            L= ~L;
                     count = count+1;
              LCD_CMD(0x01);
        delay ();
    LCD_DAT('0' + (count % 10));
}
       }
 }

void LCD_INIT()
 {
    LCD_CMD(0x01);
    delay ();
    LCD_CMD(0x38);
    delay ();
    LCD_CMD(0x0F);
    delay ();
    LCD_CMD(0x06);
    delay ();
    LCD_CMD(0x0c);
    delay ();

    LCD_CMD(0x80);
    delay ();
}
void LCD_CMD(unsigned int  value)
{
    DATA =  value;
    RS=0;
    RW=0;
    EN=1;
    delay ();
    EN=0;
    delay ();
 }

void LCD_DAT(unsigned int value)
{
    DATA= value ;

    RS=1;
    RW=0;
    EN=1;
    delay ();
    EN=0;
    delay();

}

void delay(void)
{
    int counter = 0;
    for (counter = 0; counter<1000; counter++) {
        ;
    }
}





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