/*   2864 初始化     IC：SSD1306 */

VCC外部供电方式时初始化
       write_com(0xAE);    /*display off*/ 
      
       write_com(0x00);    /*set lower column address*/       
       write_com(0x10);    /*set higher column address*/       

       write_com(0x40);    /*set display start line*/ 
      
       write_com(0xB0);    /*set page address*/     
  
       write_com(0x81);    /*contract control*/
       write_com(0xcf);    /*128*/  
     
       write_com(0xA1);    /*set segment remap  0XA0*/ 
     
       write_com(0xA6);    /*normal / reverse*/  
     
       write_com(0xA8);    /*multiplex ratio*/
       write_com(0x3F);    /*duty = 1/64*/  
     
       write_com(0xC8);    /*Com scan direction  0XC0*/   
    
       write_com(0xD3);    /*set display offset*/
       write_com(0x00);      /*0X60*/ 

       write_com(0xD5);    /*set osc division*/
       write_com(0x80);          

       write_com(0xD9);    /*set pre-charge period*/
       write_com(0xf1);      
 
       write_com(0xDA);    /*set COM pins*/
       write_com(0x12);      
 
       write_com(0xdb);    /*set vcomh*/
       write_com(0x40);       

       write_com(0x8d);    /*set charge pump disable*/
       write_com(0x10);      
 
       write_com(0xAF);    /*display ON*/    




VBAT外部供电方式时（IC内部升压）初始化
       write_com(0xAE);    /*display off*/ 
      
       write_com(0x00);    /*set lower column address*/       
       write_com(0x10);    /*set higher column address*/       

       write_com(0x40);    /*set display start line*/ 
      
       write_com(0xB0);    /*set page address*/     
  
       write_com(0x81);    /*contract control*/
       write_com(0xcf);    /*128*/  
     
       write_com(0xA1);    /*set segment remap   0XA0*/ 
     
       write_com(0xA6);    /*normal / reverse*/  
     
       write_com(0xA8);    /*multiplex ratio*/
       write_com(0x3F);    /*duty = 1/64*/  
     
       write_com(0xC8);    /*Com scan direction  0XC0*/   
    
       write_com(0xD3);    /*set display offset*/
       write_com(0x00);       

       write_com(0xD5);    /*set osc division*/
       write_com(0x80);          

       write_com(0xD9);    /*set pre-charge period*/
       write_com(0xf1);      
 
       write_com(0xDA);    /*set COM pins*/
       write_com(0x12);      
 
       write_com(0xdb);    /*set vcomh*/
       write_com(0x40);       

       write_com(0x8d);    /*set charge pump disable*/
       write_com(0x14);      
 
       write_com(0xAF);    /*display ON*/    




void write_w(unsigned char dat)
{
   unsigned char m,da;
   unsigned char j;
   da=dat;
   for(j=0;j<8;j++)
   {
     m=da;
     SCL=0;     
     m=m&0x80;
     if(m==0x80)
        {
      	  SDA=1;
        }
     else
        {
      	  SDA=0;
        }     
     da=da<<1;
     SCL=1;
    }
    SCL=0;
    SCL=1;
}
      
void write_i(unsigned char ins)
{
   start();
   write_w(0x78);
   write_w(0x00);
   write_w(ins);
   stop();
}

void write_d(unsigned char dat)
{
   start();
   write_w(0x78);
   write_w(0x40);
   write_w(dat);
   stop();
}          

 void  start()
{
  SCL=1;
  SDA=1;
  SDA=0;
  SCL=0;
}

void  stop()
{
  SCL=0;
  SDA=0;
  SDA=1;
  SCL=1;
}

void delay(unsigned int t)
{
     while(t>0)
       {
       	  t--;
       }
}