蓝桥杯单片机第十一届省赛（第一场）

主函数代码

#include<iic.h>
#include<intrins.h>sfr P4=0xc0;
sbit R3=P3^2;
sbit R4=P3^3;
sbit C4=P3^4;
sbit C3=P3^5;unsigned char code led_nodot[]={0xc0,0xf9,0xa4,0xb0,0x99,0x92,0x82,0xf8,0x80,0x90};
unsigned char code led_dot[]={0x40,0x79,0x24,0x30,0x19,0x12,0x02,0x78,0x00,0x10};
unsigned char code upn[]={0xc1,0x8c,0xc8};
unsigned int 	count_er=0;//统计错误按键数
unsigned int	Vp=0;      //参考电压
unsigned int    Vn=0;	   //PCF8591测出来的电压
unsigned int    state=0;   //窗口切换变量
unsigned int    t=0;	   //时间变量
unsigned int    t_v=0;	   //统计Vn>Vp的时间
unsigned int    count=0;   //统计下降时Vn>Vp的次数
unsigned char   led=0xff;  //保存流水灯的状态,防止数码管程序干扰
unsigned char   Vn_value;	//保存PCF8591测出来的值
bit state_v=0;				//用来界定Vn>Vp时是上升还是下降
void serve_timer_INT0(){TMOD=0x01;TH0=(65535-50000)/256;//50msTL0=(65535-50000)%256;TR0=1;EA=1;ET0=1;
}
void timer_INT0() interrupt 1 using 1{TH0=(65535-50000)/256;//50msTL0=(65535-50000)%256;t++;if(Vp>Vn){t_v++;}elset_v=0;
} 
void choose(unsigned int n){switch(n){case 4:P2=(P2 &0x1f)|0x80;break;case 5:P2=(P2 &0x1f)|0xa0;break;case 6:P2=(P2 &0x1f)|0xc0;break;case 7:P2=(P2 &0x1f)|0xe0;break;case 0:P2=(P2 &0x1f)|0x00;break;}
}
void delay(unsigned int k)	//@11.0592MHz
{unsigned char data i, j;_nop_();_nop_();_nop_();i = 11;j = 190;while(k--){do{while (--j);} while (--i);}
}
void smg_display(unsigned int n,unsigned char dat){choose(6);P0=0x01<<n;choose(7);P0=dat;delay(1);choose(0);			//防止最后一位数码管显示过亮
}
void smg_show(){
smg_display(0,upn[state]);
switch(state){case 0:smg_display(5,led_dot[Vn/100%10]);smg_display(6,led_nodot[Vn/10%10]);smg_display(7,led_nodot[Vn%10]);break;case 1:smg_display(5,led_dot[Vp/100%10]);smg_display(6,led_nodot[Vp/10%10]);smg_display(7,led_nodot[Vp%10]);break;case 2:if(count>99)smg_display(5,led_nodot[count/100%10]);if(count>9)smg_display(6,led_nodot[count/10%10]);smg_display(7,led_nodot[count%10]);break;
}
}
//unsigned char EEPROM_read(unsigned char addr);
//void EEPROM_write(unsigned char dat);
//unsigned char PCF8591_read(unsigned char addr);
void check_keyboard(){
R4=0;
R3=1;
C3=C4=1;
if(C3==0){delay(1);if(C3==0){count_er=0;	if(state==1)EEPROM_write(Vp/10);	//退出1状态时保存Vp	//除以10是因为前面乘了100state++;if(state>=3)state=0;while(!C3){smg_show();}}
}R3=0;
R4=1;
C3=C4=1;
if(C3==0){delay(1);if(C3==0){if(state==2){count_er=0;	count=0;}elsecount_er++;while(!C3){smg_show();}}
}
R4=0;
R3=1;
C3=C4=1;
if(C4==0){delay(1);if(C4==0){if(state==1){Vp+=50;count_er=0;if(Vp>500)Vp=0;}elsecount_er++;while(!C4){smg_show();}}
}
R3=0;
R4=1;
C3=C4=1;if(C4==0){delay(1);if(C4==0){if(state==1){if(Vp==0)Vp=500;elseVp-=50;count_er=0;}elsecount_er++;while(!C4){smg_show();}}}
}
void check_led(){if(t_v>=100){led=led & 0xfe;choose(4);P0=led;choose(0);}else{led=led | 0x01;choose(4);P0=led;choose(0);}if(count%2!=0){led=led & 0xfd;choose(4);P0=led;choose(0);}else{led=led | 0x02;choose(4);P0=led;choose(0);}if(count_er>=3){led=led & 0xfb;choose(4);P0=led;choose(0);}else{led=led | 0x04;choose(4);P0=led;choose(0);}
}
void get_Vn(){
Vn_value=PCF8591_read(0x03);
Vn=Vn_value*(5.0/255)*100;if(Vn<Vp && state_v==0){count++;state_v=1;}else if(Vn>Vp && state_v==1){state_v=0;}
}
void main(){
choose(4);
P0=led;
choose(5);
P0=0x00;
serve_timer_INT0();
Vp=EEPROM_read(0x00)*10;
while(1){smg_show();check_keyboard();check_led();
if(t%10==0){		//每隔0.5秒刷新一次电压Vnget_Vn();
}
}
}

iic.c文件

#include "iic.h"void IIC_Start(void)
{SDA = 1;SCL = 1;somenop;SDA = 0;somenop;SCL = 0;    
}void IIC_Stop(void)
{SDA = 0;SCL = 1;somenop;SDA = 1;
}void IIC_Ack(unsigned char ackbit)
{if(ackbit) {    SDA = 0;}else {SDA = 1;}somenop;SCL = 1;somenop;SCL = 0;SDA = 1; somenop;
}bit IIC_WaitAck(void)
{SDA = 1;somenop;SCL = 1;somenop;if(SDA)    {   SCL = 0;IIC_Stop();return 0;}else  { SCL = 0;return 1;}
}void IIC_SendByte(unsigned char byt)
{unsigned char i;for(i=0;i<8;i++){   if(byt&0x80) {    SDA = 1;}else {SDA = 0;}somenop;SCL = 1;byt <<= 1;somenop;SCL = 0;}
}unsigned char IIC_RecByte(void)
{unsigned char da;unsigned char i;for(i=0;i<8;i++){   SCL = 1;somenop;da <<= 1;if(SDA) da |= 0x01;SCL = 0;somenop;}return da;
}//void IIC_Start(void); 
//void IIC_Stop(void);  
//void IIC_Ack(unsigned char ackbit); 
//void IIC_SendByte(unsigned char byt); 
//bit IIC_WaitAck(void);  
//unsigned char IIC_RecByte(void); unsigned char EEPROM_read(unsigned char addr){
unsigned char ret;
IIC_Start(); 
IIC_SendByte(0xa0); 
IIC_WaitAck();
IIC_SendByte(addr); 
IIC_WaitAck();
IIC_Stop(); IIC_Start();
IIC_SendByte(0xa1); 
IIC_WaitAck();
ret=IIC_RecByte(); 
IIC_Ack(1); 
IIC_Stop();  
return ret;
}
void EEPROM_write(unsigned char dat){
IIC_Start(); 
IIC_SendByte(0xa0); 
IIC_WaitAck();
IIC_SendByte(0x00); 
IIC_WaitAck();
IIC_SendByte(dat); 
IIC_Ack(1); 
IIC_Stop(); 
}
unsigned char PCF8591_read(unsigned char addr){
unsigned char ret;
IIC_Start(); 
IIC_SendByte(0x90); 
IIC_WaitAck();
IIC_SendByte(addr); 
IIC_WaitAck();IIC_Start();
IIC_SendByte(0x91); 
IIC_WaitAck();
ret=IIC_RecByte(); 
IIC_Ack(1); 
IIC_Stop();  
return ret;
}
//void PCF8591_out(unsigned char dat){
//IIC_Start(); 
//IIC_SendByte(0x90); 
//IIC_WaitAck();
//IIC_SendByte(0x40); 
//IIC_WaitAck();
//IIC_SendByte(dat); //IIC_Ack(1); 
//IIC_Stop(); 
//}

iic.h文件

#ifndef _IIC_H
#define _IIC_H#include "regx52.h"
#include "intrins.h"#define somenop {_nop_();_nop_();_nop_();_nop_();_nop_();}
#define SlaveAddrW 0xA0
#define SlaveAddrR 0xA1sbit SDA = P2^1;  /* ˽ߝП */
sbit SCL = P2^0;  /* ʱדП */void IIC_Start(void); 
void IIC_Stop(void);  
void IIC_Ack(unsigned char ackbit); 
void IIC_SendByte(unsigned char byt); 
bit IIC_WaitAck(void);  
unsigned char IIC_RecByte(void); 
unsigned char EEPROM_read(unsigned char addr);
void EEPROM_write(unsigned char dat);
unsigned char PCF8591_read(unsigned char addr);
//void PCF8591_out(unsigned char dat);#endif