UART transmitting interrupt handler

Hello

I am facing a problem in the following code.

code :-

#include "LPC318x.h"
void IRQ_HANDLER(void) __irq
{ PIO_OUTP_SET = 0x7EFFFFFF; PIO_OUTP_SET = 0x7EFFFFFF;
}

int main (void)
{ unsigned int i=0; SYSCLK_CTRL = 0x00000140; HCLKPLL_CTRL = 0x00014024; UARTCLK_CTRL = 0x0F; MIC_ER = 0x000007C0; U5LCR = 0x03; U5CLK = 0x0000020E; UART_CLKMODE = 0x00000550; U5FCR = 0x00; U5IER = 0x07; U3DLL = 27;

while(1) {

U5THR = 0x55; U5THR = 0xAA; }

}

When i enable UART5 interrupt by using MIC_ER interrupt is generated as it should be. But after transmitting the data it jumps to an unusual location
0x000002d4.
But it doesnt go to IRQ handler.
If i don't enable the interrupt using MIC_ER then it executes only while(1) loop.
The main aim of the program is to blink the LED after send data through UART5 as mentioned in the IRQ interrupt handler.

Thank You,

Ankit Thakkar.