//Lesson1-EX4 Tests an input
#include <16F877A.h>
void main()
{
   int x;                // Declare variable
   output_D(0);             // Clear all outputs

  while(1)                // Loop always
    {
         x = input(PIN_C0);          // Get input state
        if(x == 1)output_high(PIN_D0);    // Change output 
        else output_low(PIN_D0);
   }
}

//Lesson1-EX4 Tests an input
#include <16F877A.h>
void main()
{
   //int x;                // Declare variable
   output_D(0);             // Clear all outputs

  while(TRUE)                // Loop always
    {
         
        if(input(PIN_C0))output_high(PIN_D0);    // Change output
        else output_low(PIN_D0);
   }
}

#include <16F877A.h>
#use delay(clock=4000000)

void high_b6_low_b7() {
output_high(PIN_B6);
output_low(PIN_B7);
}

void low_b6_high_b7() {
output_low(PIN_B6);
output_high(PIN_B7);
}
///////////////////////////////////////////////////////////

#INT_EXT
void RB0_handler() {
low_b6_high_b7();
delay_ms(500);
high_b6_low_b7();
}
///////////////////////////////////////////////////////////
/*
* Keep B6 on and B7 off. Pressing the button causes interrupt:
* B6 off and B7 on, delay half second, then B6 on and B7 off
*/
void main() {
enable_interrupts(GLOBAL); // enable all interrupts
enable_interrupts(INT_EXT); // enable external interrupt from pin RB0/INT

high_b6_low_b7();

while (true) {
// do nothing
}
}

#INCLUDE <16F877A.h>
#use delay(clock=4000000)

#int_TIMER0
void TIMER0_isr(void) {
   output_toggle(PIN_B0);
   set_timer0 (26);  }               //Set initial value  

void main() {
  setup_timer_0(RTCC_INTERNAL|RTCC_DIV_2);   //Timer0 setup : internal & divided by 2 

  set_timer0 (26);                    //Set initial value  
  enable_interrupts(INT_TIMER0);       //Enable local timer0 interrupt 
  enable_interrupts(global);           //Enable global interrupts 

  while (1);         //endless loop 
}

VT=VB * RT/R1+RT
VB*RT = VT*R1 + VT * RT 
VT*R1= RT(VB-VT)
RT = VT*R1/(VB-VT) = 10000VT/(5-VT)

#include "16f877A.h"
#device adc=10
#use delay(clock=4000000)
#include <math.h>                //Needed for mathematical calculations
#include <lcd.c>

void main() {

   float tv,tr,temp,y;                 //Equation variables
   int16 value;
   
   lcd_init();
   
   setup_port_a( ALL_ANALOG );
   setup_adc( ADC_CLOCK_INTERNAL );
   set_adc_channel( 0 );
   delay_us(10);
   
   do {
      value = Read_ADC();
      
      tv = 5.0 * value / 1024.0;
      
      tr = tv * 10000.0 / (5.0 - tv);
      
      y = log(tr/20000.0);
       y = (1.0/298.15) + (y *(1.0/4050.0));
       
      temp=1.0/y;
      temp = temp -273.15;
      
      printf(lcd_putc,"\nT = %04.2fC", temp);
   } while (TRUE);
}

value = Read_ADC();
 tv = 5.0 * value / 1024.0;

RT = 10000VT/(5-VT)

tr = tv * 10000.0 / (5.0 – tv) ;

y = log(tr / 20000.0);

#include <math.h>

temp = 1.0 / y ;

temp = temp – 273.15 ;

printf(lcd_putc , “\nT = %04.2fC”, temp);

#include <16F877A.h>
#use delay(clock= 4000000)

#define use_portb_kbd TRUE
#define use_portb_lcd TRUE
#include <lcd.c>
#include <kbd.c>
        
void main() {
   char k; 
   int  x;
          
   lcd_init(); 
   kbd_init();
   port_b_pullups(TRUE); 

   lcd_putc("\fPreee Key...\n"); // Initially clear screen and print fPreee Key... , then new line 
                                    
   while (TRUE) {
      k=kbd_getc(); // get key as character , save in k
      x=k-48;                             //convert character k to numeric value x 
      if(k!=0){  // if any key is pressed
        
        if(k=='*') // if k is * 
          lcd_putc('\f'); // clear screen 
          
        else
           lcd_putc(k);             //  r print character k 
           delay_ms(1000);
           
           //after that or both cases
           printf(lcd_putc,"\f Char=%c",k); // clear and print k as character %c 
           delay_ms(1000);
           
           printf(lcd_putc,"\f Char=%u",k); //clear and Print k as ASCII value %u
           delay_ms(1000);
           
           printf(lcd_putc,"\f Nume=%u",x); //clear and Print the numerical value of the character
           delay_ms(1000);
           
           lcd_putc("\fPress Key...\n");
      }
   }
}

#include <16F877a.h>
#use delay(clock= 4000000)
//#use standard_io(a) 
#define use_portb_kbd TRUE
#define use_portb_lcd TRUE
#include <lcd.c>
#include <kbd.c>
//#include <stdlib.h>

#rom 0x2100={'7','2','3'}  // Save data 7 , 2 , 3 in position 0,1 and 2 of the EEPROM respectively 
                           
void main() {
   char k;
   int i;
   char data[3], key[3];  //Storage arrays for data and key 

   lcd_init();
   kbd_init();
   port_b_pullups(TRUE);

   while (TRUE) {
   i=0;            //array index position

   printf(lcd_putc,"\fPress Key 1\n");  //clear screen , print Press Key 1 , go to a new line 

   while(i<=2){                //Three data
      k=kbd_getc();            //Read keypad
      if (k!=0)                //If any key is Pressed 
         {data[i]=k;           //It is stored in the corresponding position
          i++;                //of the array
          printf(lcd_putc,"\fPress Key %u\n",i+1);  //Next item
         }
    }

   for (i=0;i<=2;i++) {             //EEPROM passes data to the key array 
     key[i]=read_eeprom(i);}

   if ((data[0]==key[0])&&(data[1]==key[1])&&(data[2]==key[2]))
      { printf(lcd_putc,"\fDoor Open"); //Compares the data with the key
        output_high(PIN_A0);                //If equal gives pulse to relay
        delay_ms(2000);
        output_low(PIN_A0);}
   else printf(lcd_putc,"\fDoor Closed");  //key error
   delay_ms(1000);
   }
}

#include <16f877A.h>
#USE DELAY (CLOCK=4000000)
#define use_portb_kbd TRUE
#INCLUDE <kbd.c>
//#USE STANDARD_IO (a)

VOID MAIN()
{
   CHAR k,kant='0';     //Keyboard k value, previous value k keyboard
   char PWMH=0,PWML=0;  //High and low half period
   
   kbd_init();
   PORT_B_PULLUPS(TRUE);

WHILE (1) {                    //Infinite loop 
      k=kbd_getc();            //Reads ASCII value of the pressed key 
      if (k=='\0') k=kant;     //If key (\ 0) is pressed the former value is used
      if ((k=='*') || (k=='#')) k='0';  //Pressing * or # is assigned a zero value.
      kant=k;                          //Pressed key is saved
       k=k-48;                         //It becomes a numerical value ASCII
       PWMH=k*28;                     //Key ratio value and half period Alto.
       PWML=255-PWMH;                 //Under half period
      for(PWMH;PWMH>0;PWMH--){        //Getting high-level output
       OUTPUT_HIGH(PIN_A0);}
      for(PWML;PWML>0;PWML--){      //Getting output at low level
      OUTPUT_LOW(PIN_A0);}
  }
}