#include"includes.h"
unsigned char i=0;
unsigned char flag;
void mydelay(unsigned int j)
{
    unsigned int i;
	for(i=0;i<j;i++);

}
void dac_senddata(unsigned char da)	        //向DAC908發(fā)送數(shù)據(jù)
{
    P0=da;
	CLK=0;
    CLK=1;
	CLK=0;

}

void Dac_output() interrupt 5 using 0
{
	 TF2=0;
	  if(flag==0)
     {
	     i+=4;
		 if(i>=128)
		 {flag=1;
		  i=128;
		  }

	 }
	 else if(flag==1)
	 {
	      i-=4;
	      if(i<=0)
		  {
		   flag=0;
		   i=0;
		   }
	 }
	 dac_senddata(i);
	 
}