Problem in Creating Nano Secs Delay using 1768 in ISP mode

Hi,
i am trying to create Nano secds delay, but i got delay in micro secds so, plz help me ...

my timer configurations are......

void Timer_Init()
{
                LPC_SC->PCONP                =       (1<<1);                                                   LPC_TIM0->TCR        |= 1 << 0;
                LPC_TIM0->PR          = 3;
          LPC_TIM0->MR0       = 2;

    LPC_TIM0->MCR    |= 1 << 0;
    LPC_TIM0->MCR    |= 1 << 1;
    NVIC_EnableIRQ(TIMER0_IRQn);

                LPC_TIM0->TCR        |= (1<<1);
                LPC_TIM0->TCR &= ~(1<<1);
}
</prev>
Here i am not using PLL here...PCLK=12MHz.... suzzes me which values are Sutable for MR0 And PR0.....to create nano secands Delay...