void delay_ms(unsigned int n)
{
  	unsigned int i;
	for(;n>0;n--){for(i=1;i<(unsigned int)(MHZ*143-2);i++);}
}
void delay_1us()
{
asm("nop");
}

void delay_us(unsigned int i)
{
  	for(;i>0;i--)
	{
	delay_1us();
	}
}