LPC1114 GPIO P1.0~P1.3 doesn't work

I'm not able to make it work the GPIO P1.0-P1.3 of LPC1114. Both in hardware as in keil debug the GPIO's P1.0 dont clear.

int main()
{
        /* Enable AHB clock to the GPIO domain. */
        LPC_SYSCON->SYSAHBCLKCTRL |= (0x1UL << 16);  /* enable clock for IOCON      */
        LPC_SYSCON->SYSAHBCLKCTRL |= (0x1UL << 6);  /* enable clock for GPIO      */

        LPC_IOCON->R_PIO1_0 |= 0x01; /* P1.0 as GPIO      */
        LPC_GPIO1->DIR  |= (1UL <<  0);                /* P1.0 as GPIO      */
        LPC_GPIO1->DATA &= ~(1UL <<  0);   /* Clear P1.0      */ //*********Don't work

        while(1);
}

what's wrong with this code?