problem with interrupt subroutine

Code C - [expand]
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#include <LPC214X.H>
#include <stdio.h>
 
void init_Eint1(void);
__irq void IRQ_Handler(void);
int main(void)
{
    PINSEL0=0X00000000;
    IODIR0=0X00000001;
init_Eint1();
        
}
 
__irq void IRQ_Handler(void)    //irq subroutine
{
    
    EXTINT=0X00000001;      //initialize the EINT0
    if(EXTINT==0)
    {
        IOSET0=0X00000001;
    }
    else
    {
        IOCLR0=0X00000001;
    }
    VICVectAddr=0x00000000;
}
 
void init_Eint1(void)
{
    
    EXTINT=0X00000001;
    PINSEL1=0X00000001;     
    IOCLR0=0X00000001;
    EXTMODE=0X00000010;     //edge sensitive mode
    EXTPOLAR=0X0000000;     //falling edge
    VICIntEnable=0x00004000;
    VICVectAddr0=(unsigned long) IRQ_Handler;
    VICVectCntl0=0x0000002E;
}