AVR 的SPI双机通信的仿真程序

#include "display.h" //===================MAX7219的核心函数，接收单片机的数据===================== void SEND(unsigned char add,unsigned char dat)//发送2个字节的子函数,第一个字节为地址,第二个字节为操作数 { unsigned char ads,j,x; unsigned int i; i=0; MAX7219_LOAD_0;//load=0 while(i<16) { // if(add==1||add==5) dat=dat|0x80; //小数点问题解决 if (i<8){ads=add;} else {ads=dat;} for(j=8;j>=1;j--) { x=ads&0x80; if (x==0){MAX7219_DIN_0;} else {MAX7219_DIN_1;} ads=ads<<1; MAX7219_CLK_1;//clk=1 MAX7219_CLK_0;//clk=0 } i=i+8; } MAX7219_LOAD_1;//load=1 } //===================================== //==============SEG亮度================ void SEG_LIGHT(unsigned light) { SEND(0x0a,light&0x0f); } //=================================== //==============SEG开================ void SEG_OPEN(void) { SEND(0x0c,0x01); } //=================================== //==============SEG关================ void SEG_CLOSE(void) { SEND(0x0c,0x00); } //=================================== //==============SEG清屏============== void SEG_CLEAR(unsigned char part) { switch(part) { case 0://左 { SEND(0x01,0x0f); SEND(0x02,0x0f); SEND(0x03,0x0f); SEND(0x04,0x0f); }break; case 1://右 { SEND(0x05,0x0f); SEND(0x06,0x0f); SEND(0x07,0x0f); SEND(0x08,0x0f); }break; default://全部 { SEND(0x01,0x0f); SEND(0x02,0x0f); SEND(0x03,0x0f); SEND(0x04,0x0f); SEND(0x05,0x0f); SEND(0x06,0x0f); SEND(0x07,0x0f); SEND(0x08,0x0f); }break; } } //==============SEG初始化============= void SEG_INIT(void) { MAX7219_OUT_DDR|=(1<<MAX7219_CLK_PORT)|(1<<MAX7219_DIN_PORT)|(1<<MAX7219_LOAD_PORT); MAX7219_OUT_PORT|=(1<<MAX7219_CLK_PORT)|(1<<MAX7219_DIN_PORT)|(1<<MAX7219_LOAD_PORT); SEND(0x0c,0x01); SEND(0x0b,0x07); SEND(0x0a,0x05); SEND(0x09,0xff); SEG_CLEAR(3); } //=============SEG左四显示数字============== void SEG_L(unsigned int number) { unsigned char i=4; SEND(0x01,0x0f); //先清除左四位,左四位黑屏 SEND(0x02,0x0f); SEND(0x03,0x0f); SEND(0x04,0x0f); if(number>9999)//要显示的数值超过4位，则显示４个Ｈ { SEND(0x01,0x0c); SEND(0x02,0x0c); SEND(0x03,0x0c); SEND(0x04,0x0c); } else//小于四位可以显示 { /* for(i=4;i>0;i--) { SEND(i,number%10); number=(number-number%10)/10; } */ do { SEND(i,number%10); number=(number-number%10)/10; i--; }while(number>=1); } } //===================================== //=============SEG右四显示数字============== void SEG_R(unsigned int number) { unsigned char i=8; SEND(0x05,0x0f); //先清除右四位，右四位黑屏 SEND(0x06,0x0f); SEND(0x07,0x0f); SEND(0x08,0x0f); if(number>9999)//要显示的数值超过4位，则显示４个Ｈ { SEND(0x05,0x0c); SEND(0x06,0x0c); SEND(0x07,0x0c); SEND(0x08,0x0c); } else//小于四位可以显示 { /* for(i=8;i>4;i--) { SEND(i,number%10); number=(number-number%10)/10; } */ do { SEND(i,number%10); number=(number-number%10)/10; i--; }while(number>=1); } } //===================================