Dspic input captur Problem

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# include <p33FJ32GP204.h>
#include "delay.h"
unsigned int i;
unsigned int timePeriod= 0; 
unsigned int freq= 0;
unsigned int current_value=0,previous_value=0;
 
#define FCY 7372800
 
 
/***INPUT CAPTURE_SETUP***/
void IC1_SETUP (void)
{
    RPINR7bits.IC1R=0;          /* pin RB0 is chosen as input pin*/
    IC1CONbits.ICM=1;           /*Capture every edge, rising and falling*/
    IC1CONbits.ICTMR = 1;   // Select Timer2 as the IC1 Time base
    IC1CONbits.ICBNE=0;     /*Input capture buffer is empty*/
    IC1CONbits.ICI=0;           /*Interrupt on every capture event*/
    //IC1CONbits.ICTSEL=1;      /*TMR2 contents are captured on captured event*/
    IC1CONbits.ICSIDL=0;        /*Input capture module will continue to operate in CPU Idle mode*/
    IPC0bits.IC1IP = 1;         // Setup IC1 interrupt priority level
    IFS0bits.IC1IF = 0;         /*Interrupt bit is cleared*/
    IEC0bits.IC1IE = 1;         /*Set the IC1 interrupt enable bit */
}
 
/***TIMER_SETUP***/
void TIMER2_SETUP (void)
{
    
    T2CONbits.TON = 0;          //Stops the Timer2 and reset control reg. 
    T2CONbits.TCS=0;            /*Using INTERNAL Clock */
    T2CONbits.T32=0;            /*TMRx and TMRy form a 16-bit timer*/
    T2CONbits.TCKPS=0;          /*Using 1:1 prescale value*/
    T2CONbits.TGATE=0;          /*Timer Gate Accumulation Disabled*/
    T2CONbits.TSIDL=0;          /*Continue in Idle Mode*/
    TMR2 = 0x00;                //Clear contents of the timer register
//  PR2 = 9;                    //Load the Period register with the value 0xFFFF
    IFS0bits.T2IF = 0;          //Clear the Timer2 interrupt status flag
    IEC0bits.T2IE = 1;          //Enable Timer2 interrupts
    T2CONbits.TON = 1;          //Start Timer2
 
}
 
 
/****INTERRUPT FOR IC1****/
// Capture Interrupt Service Routine 
void __attribute__((__interrupt__)) _IC1Interrupt(void)
{   
    //T2CONbits.TON = 1; 
 
    current_value=IC1BUF;
    IFS0bits.IC1IF = 0;
    if(current_value>previous_value)
    { 
        timePeriod =2* (current_value-previous_value); 
    }
    else
    { 
        timePeriod = 2*((PR2 - previous_value) + current_value) ;
    } 
    freq=1000000L/timePeriod;
        previous_value=current_value;
}
 
void delay (void)
{
    int i;
 
    for (i = 0; i < 10000; i++)
    {
    };
 
}
 
 
void main (void)
{
//  AD1PCFGL = 0xFFFF; 
    TRISC = 0b11110100 ;//sets the RB0 & RB1 pin to an output 
    PORTC = 0b00000001 ;//sets the RB0 pin to high 
    delay();
    TRISCbits.TRISC3 = 0;   // RC3 output - U1TX pin
    TRISCbits.TRISC4 = 1;   // RC4 input - U1RX pin 
 
 
 
    TIMER2_SETUP();         /*Calling the Timer Setup Function*/
 
    IC1_SETUP();            /*Calling the Input Setup Function*/
 
    while(1)
    {
 
        
        if(freq==50)
        {
            delay();
            PORTC = 0b00000010 ;//sets the RB1 pin to high          
            delay();
            PORTC=0;
        }
    }
}