/*---------------------------------------延時函數(shù)-------------------------------------*/ 

/*-----------------------------------------------------------------------
延時函數(shù)
系統(tǒng)時鐘：8M
-----------------------------------------------------------------------*/
void delay_1us(void)                 //1us延時函數(shù)
  {
   asm("nop");
  }

void delay_nus(unsigned int n)       //N us延時函數(shù)
  {
   unsigned int i=0;
   for (i=0;i<n;i++)
   delay_1us();
  }

void delay_1ms(void )  //延時1ms 
{ 
   unsigned int i ; 
   unsigned char xtal; 
   xtal=4; 
   for (i=1;i<(xtal*143-2);i++) 
   { 
    ; 
   }    
} 

void delay_nms(unsigned int n)  //延時nms 
{ 
   unsigned int i=0 ;  
   for(i=0;i<n;i++) 
   { 
    delay_1ms();  
   } 
}