//max7219 led drive program
//for 51 mcu
//designed by zhaoliang
//2005-6-12 13:52
＃i nclude<reg51.h>

/***********************************************************************/
//common part
#define  HIGH     1
#define  LOW      0
#define  TRUE      1
#define  FALSE      0
#define  ZERO      0
#define  MSB       0x80
#define  LSB       0x01
//max7219 part
#define  DECODE_MODE   0x09
#define  INTENSITY     0x0A
#define  SCAN_LIMIT    0x0B
#define  SHUT_DOWN     0x0C
#define  DISPLAY_TEST  0x0F

//pin defined
/***********************************************************************/
//change this part at different board
sbit LOAD=P1^2; //MAX7219    Load-Data Input:    rising edge  pin 12
sbit DIN=P1^1; //MAX7219    Serial-Data Input:   rising edge  pin 1
sbit CLK=P1^0; //MAX7219   Serial-Clock Input:  maximum 10MHz  pin 13

//function define
/***********************************************************************/
void Write_Max7219_byte(unsigned char temp);//write max7219 a byte
void Write_Max7219(unsigned char address,unsigned char dat);//write max7219 command and data
void Init_Max7219(void);//Initize max7219

//test program display from 1~8
/***********************************************************************/
void main(void)
{
 unsigned char i;
 Init_Max7219(); 
 while(TRUE)
 { 
  for(i=1;i<9;i++)
  {
   Write_Max7219(i,i);
  }
 }
}
/***********************************************************************/
void Write_Max7219_byte(unsigned char temp)
{
 unsigned char i;
 for (i=0;i<8;i++)    
  {
   CLK=LOW;
     DIN=(bit)(temp&MSB);     
     temp<<=1; 
     CLK=HIGH;
   }
}
/***********************************************************************/
void Write_Max7219(unsigned char address,unsigned char dat)
{
 LOAD=LOW;
   Write_Max7219_byte(address);
   Write_Max7219_byte(dat);
  LOAD=HIGH;                
}
/***********************************************************************/
void Init_Max7219(void)     
{
 Write_Max7219(SHUT_DOWN, 0x01);   //Normal Operation XXXXXXX1 Shutdown Mode   XXXXXXXX0
 Write_Max7219(DISPLAY_TEST, 0x00);   //Normal Operation XXXXXXX0 Display Test Mode XXXXXXXX1
 Write_Max7219(DECODE_MODE, 0xff);   //Decode Mode Select D7~D0 1 B decode 0 No decode
 Write_Max7219(SCAN_LIMIT, 0x07);   //SCAN LIMIT 0~7 0xX0~0xX7
 Write_Max7219(INTENSITY, 0x04);   //Set Intensity   0xX0~0xXf
}