gistfile1.txt

Enter file contents here// 10/21/2015 Fall Microcontrolers
#include <18f4520.h>
#use delay(clock=20000000)
#fuses HS, NOWDT, NOLVP
#include "../Library/18f4520ptr.h"
#include "../Library/modifiedlcd.h"

unsigned int OFCnt=0;
#INT_TIMER1    // Counter Overflows
void Int_timer1_isr(){
   OFCnt++;
}

unsigned int32 tstart, tstop, dT;
#INT_CCP2
void int_ccp2_isr(){
   tstop = *CCPR2;     //Get the time off the system...
   dT = (OFCnt*0x10000)-tstart+tstop;
   tstart = tstop;
   OFCnt = 0;
}

main(){
   float time;
   lcd_init();
   // Assuming your prescaler is = to 1   & your clock cycle is 20,000,000

   // Setup Overflow
   T1CON->TMR1ON=1;
   T1CON->TMR1CS=0;
   T1CON->T1CKPSx=0;  // Setting PS to 1

   // Setup my Capture
   CCP2CON->CCPxMx=4;

   // Setup my Interrupts
   PIE1->TMR1IE=1;    // Overflow Interupt
   PIE2->CCP2IE=1;
   INTCON->GIE=1;
   INTCON->PEIE=1;
   while(1){
      time=dT*0.2e-6;      // PS 1 and Fosc 20m
      printf(lcd_putc,"\f Freq=%f", 1/time);
      delay_ms(300);
   }
}