源代码：

#include <reg51.h>

#include <intrins.h>

sbit Max7221CS  = P3^1;

sbit Max7221DIN = P3^0;

sbit Max7221CLK = P3^2;

unsigned char code DisplayBuffer[8]={0,1,2,3,4,5,6,7};

void WriteMax7221(unsigned char Address,unsigned char Data)

{

unsigned char i;

Max7221CS = 0;

for (i=0;i<8;i++)

{

Max7221CLK = 0;

Max7221DIN = (Address&(0x80>>i)) ? 1:0;

_nop_();

_nop_();

Max7221CLK = 1;

_nop_();

_nop_();

}

for (i=0;i<8;i++)

{

Max7221CLK = 0;

Max7221DIN = (Data&(0x80>>i)) ? 1:0;

_nop_();

_nop_();

Max7221CLK = 1;

_nop_();

_nop_();

}

Max7221CS = 1;

}

void InitialMax7221(void)

{

WriteMax7221(0x0A,0x07);

WriteMax7221(0x0B,0x07);

WriteMax7221(0x0C,0x01);

WriteMax7221(0x09,0xFF);

}

void Max7221Display(unsigned char *buffer)

{

unsigned char i;

for(i=0;i<8;i++)

{

WriteMax7221(i+1,*(buffer+i));

}

}

void main(void)

{

InitialMax7221();

Max7221Display(&DisplayBuffer[0]);

while(1);

}