problem in lpc2138 external interrupt

hai
i am doing basic programs in lpc2138 ARM controller
problem is exter nal interrupt is only once generates
but again it is not generate.send me what is the problem.this is my code

//*****************************************************

#include<lpc213x.h> #include <stdio.h>

extern void init_serial(void); unsigned char temp; void EXTINTVectoredIRQ (void)__irq;

void EXTINTVectoredIRQ (void)__irq { unsigned int temp; IOCLR1=0XFFFFFFFF; EXTINT=0X00000020; temp = VICIRQStatus; printf("isr_temp=%x\n",temp); VICVectAddr15=0; }

int main() { init_serial(); //printf("temp\n"); IODIR1=0X00FF0000; IODIR0=0X20000000; PINSEL1=0X00000000; PINSEL0=0X200000C5; //interrupt pin p0.14
EXTMODE = 0; // LEVEL sensitive mode on EINT1
EXTPOLAR = 0;
VICDefVectAddr = 0x0000002f;
VICIntSelect |=0x00000000;
VICVectAddr15 |=(unsigned int)EXTINTVectoredIRQ;
VICVectCntl15 |= 0x0000002f;
VICIntEnable |=0x00008000;
PINSEL0=0X20000005;
temp = VICIRQStatus; printf("temp=%x\n",temp); while(1) { IO1CLR =0X00FF0000; IOSET1 =0x00FF0000;

} }

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