text2.c

12位串行DA,精度可以满足较高的要求,自己做了一下,感觉效果还不错

#include<AT89x51.h>

sbit clk=P3^2;
sbit sri=P3^1;
sbit load=P3^0;


//驱动MAX543
void wr543(unsigned int dat)
{
		unsigned int mid;
		unsigned char i;
		unsigned int x;
		mid=(dat<<4);
		load=1;
		clk=0;
		for(i=0;i<12;i++)
		{  sri=0;
			x=mid&0x8000;
			if(x==0)
			{
				sri=0;
			}	
			else 
			{
				sri=1;
			}
			clk=1;
			mid=mid<<1;
			clk=0;	
		}
		load=0;
	
}	

 unsigned  char code sin[]={ 128, 131, 134, 137, 140, 144, 147, 150, 153, 156, 159, 162, 165, 168, 171, 174,
 177, 180, 182, 185, 188, 191, 194, 196, 199, 201, 204, 206, 209, 211, 214, 216, 
 218, 220, 222, 224, 226, 228, 230, 232, 234, 236, 237, 239, 240, 242, 243, 244, 
 246, 247, 248, 249, 250, 251, 251, 252, 253, 253, 254, 254, 254, 255, 255, 255, 
 255, 255, 255, 254, 254, 254, 253, 253, 252, 252, 251, 250, 249, 248, 247, 246,
 245, 244, 242, 241, 240, 238, 236, 235, 233, 231, 229, 227, 225, 223, 221, 219, 
 217, 215, 212, 210, 208, 205, 203, 200, 197, 195, 192, 189, 187, 184, 181, 178, 
 175, 172, 169, 167, 164, 160, 157, 154, 151, 148, 145, 142, 139, 136, 133, 130, 
 126, 123, 120, 117, 114, 111, 108, 105, 102, 99 , 96 , 92 , 89 , 87 , 84 , 81,  
 78 , 75 , 72 , 69 , 67 , 64 , 61 , 59 , 56 , 53 , 51 , 48 , 46 , 44 , 41 , 39,  
 37 , 35 , 33 , 31 , 29 , 27 , 25 , 23 , 21 , 20 , 18 , 16 , 15 , 14 , 12 , 11,  
 10 , 9  , 8  , 7  , 6  , 5  , 4  , 4  , 3  , 3  , 2  , 2  , 1  , 1  , 1  , 0,   
 0  , 1  , 1  , 1  , 2  , 2  , 3  , 3  , 4  , 5  , 5  , 6  , 7  , 8  , 9  , 10,  
 12 , 13 , 14 , 16 , 17 , 19 , 20 , 22 , 24 , 26 , 28 , 30 , 32 , 34 , 36 , 38, 
 40 , 42 , 45 , 47 , 50 , 52 , 55 , 57 , 60 , 62 , 65 , 68 , 71 , 74 , 76 , 79,  
 82 , 85 , 88 , 91 , 94 , 97 , 100, 103, 106, 109, 112, 116, 119, 122, 125, 127
 }; 	
 

void main(void)
{
	unsigned int j;
	while(1)
	{	
		for(j=0;j<256;j++)
		wr543(j);
	/*	for(j=0;j<256;j++)
		sri=0;
		for(j=0;j<256;j++)
		sri=1;*/		
		
		
	}
}