problem in autobauding in lpc2148

I was programming lpc2148 using max232, crystal 11.0592MHz at 2400 baudrate using flash
magic,but when i loaded the below code the problem of "operation failed ,Can't Autobaud" comes in the picture.
So, now how to erase the chip.
should i change crystal to 12MHz or it doesn't matter??
else what changes i have to make???
Please help help!!!

CODE::

/****************************************************************************** * * WinARM Demo P0.16 blink * *****************************************************************************/

#include "types.h"
#include "LPC214x.h"
#include "config.h"
#include "armVIC.h"

#define IOPINS016 16
/****************************************************************************** * * Function Name: lowInit() * * Description: * This function starts up the PLL then sets up the GPIO pins before * waiting for the PLL to lock. It finally engages the PLL and * returns * * Calling Sequence: * void * * Returns: * void * *****************************************************************************/
static void lowInit(void)
{ // set PLL multiplier & divisor. // values computed from config PLLCFG = PLLCFG_MSEL | PLLCFG_PSEL;

// enable PLL PLLCON = PLLCON_PLLE; PLLFEED = 0xAA; // Make it happen. These two updates PLLFEED = 0x55; // MUST occur in sequence.

// setup the parallel port pin IO0CLR = (1<<IOPINS016); // clear the ZEROs output IO0SET &= ~(1<<IOPINS016); // set the ONEs output IO0DIR =(1<<IOPINS016); // set the output bit direction

// wait for PLL lock while (!(PLLSTAT & PLLSTAT_LOCK)) continue;

// enable & connect PLL PLLCON = PLLCON_PLLE | PLLCON_PLLC; PLLFEED = 0xAA; // Make it happen. These two updates PLLFEED = 0x55; // MUST occur in sequence.

// setup & enable the MAM MAMTIM = MAMTIM_CYCLES; MAMCR = MAMCR_FULL;

// set the peripheral bus speed // value computed from config.h VPBDIV = VPBDIV_VALUE; // set the peripheral bus clock speed
}

/**/
static void sysInit(void)
{ lowInit(); // setup clocks and processor port pins

// set the interrupt controller defaults
#if defined(RAM_RUN) MEMMAP = MEMMAP_SRAM; // map interrupt vectors space into SRAM
#elif defined(ROM_RUN) MEMMAP = MEMMAP_FLASH; // map interrupt vectors space into FLASH
#else
#error RUN_MODE not defined!
#endif

VICIntEnClear = 0xFFFFFFFF; // clear all interrupts VICIntSelect = 0x00000000; // clear all FIQ selections VICDefVectAddr = (uint32_t)reset; // point unvectored IRQs to reset() }

static void _delay(uint32_t N)
{ for (uint32_t i=0; i<N;i++);
}

int main(void)
{ sysInit(); for (;;) { IO0CLR = (1<<IOPINS016); // clear the ZEROs output _delay(900000); IO0SET = (1<<IOPINS016); // set the ONEs output _delay(900000); }

return 0;
}