max7219.h

直接数字频率合成,我在全国电子设计大赛的时候所用的程序

/*************************************************
max7219的驱动程序
****************************************************/
#ifndef _max7219_h
#define _max7219_h

#include <reg52.h>			    	// 引用标准库的头文件
#include <intrins.h>

#define uchar unsigned char 
#define uint unsigned int
/*****************7219数据端口*******************/
sbit max7219_din=P0^5;	    
sbit max7219_load=P0^4;
sbit max7219_clk=P0^3;

 /************定义7219的位选***************/
#define k0 0x01	
#define k1 0x05
#define k2 0x07
#define k3 0x03
#define k4 0x04
#define k5 0x08
#define k6 0x06
#define k7 0x02
//uchar k[8]={k0,k1,k2,k3,k4,k5,k6,k7};

void send_7219(uchar add,uchar dat)
 {
   uchar ads,i,j;
   max7219_load=0;
   i=0;
  while(i<16)
   {
    if(i<8)                   //低八位先送地址
     { ads=add;}
    else                        //送数据
     {ads=dat;}
      for(j=8;j>0;j--)
      {
       max7219_clk=0;
       max7219_din=ads&0x80;
       ads=ads<<1;
       max7219_clk=1;  
      }
      i=i+8;
    }
    max7219_load=1;
 }

 /*****************初始化7219 ********************/

void write_7219()
 {
  send_7219(0x0c,0x01);
  send_7219(0x0b,0x07);
  send_7219(0x0a,0x04);
  send_7219(0x09,0xff);
 } 

void init_7219()
 {
  send_7219(k0,0);
  send_7219(k1,0);
  send_7219(k2,0);
  send_7219(k3,0);
  send_7219(k4,0);
  send_7219(k5,0);
  send_7219(k6,0);
  send_7219(k7,0); 
 }

 #endif