【第十三届蓝桥杯单片机省赛冲刺-巩固练习重点】

第十三届蓝桥杯单片机省赛冲刺-巩固练习

下面内容来自小蜜蜂老师公众号更新内容，讲了AT24C02 、PCF8591、以及led和数码管冲突问题，在更新的内容中小蜜蜂老师换了之前对锁存器初始化的写法，主要是加了一句所有锁存器都不选择的代码，更好的可以避免不同操作之间的影响，其次在进行锁存器操作端口赋值的时候也换了写法，之前是先选择要操作的锁存器后再进行赋值，现在是先将要赋的值送到端口然后在打开锁存器。

【【第十三届蓝桥杯单片机省赛冲刺-巩固练习重点】】小蜜蜂老师操作总结 yyds

在编程中应该把握的原则是， P0端口的数据只送到目标外设。我的一个经验是：在上电初始化完成时，把所有外设连接的锁存器关闭；在需要对目标外设传输数据时，先把数据送到P0端口，然后再打开外设对应的锁存器，用完马关闭锁存器。保证在不需要的时候P0端口的变化不影响任何外设，在需要控制时，外设只接收正确的信息

一、灯闪烁与数码管计数

#include "reg52.h"sbit LED1 = P0^0;sbit LED2 = P0^1;sbit LED8 = P0^7;unsigned char led_stat = 0xff;unsigned char value1 = 0,value2 = 0;unsigned char code smg_data[] = {0xC0,0xF9,0xA4,0xB0,0x99,0x92,0x82,0xF8, 0x80,0x90};void SMG_Display_Data(void);//1.简单延时void delay(unsigned int t){while(t--);}void Delay_s(unsigned int t){while(t--){SMG_Display_Data();//在延时期间保持数码管刷新}}//2.锁存器初始化void Init_74HC138(unsigned char channel){switch(channel)	{case 4:P2 = (P2 & 0x1f) | 0x80;break;//Y4输出0 ， LED控制case 5:P2 = (P2 & 0x1f) | 0xa0;break;//Y5输出0 ， 蜂鸣器和继电器控制case 6:P2 = (P2 & 0x1f) | 0xc0;break; //Y6输出0 ， 数码管位选case 7:P2 = (P2 & 0x1f) | 0xe0;break;//Y7输出0 ， 数码管段码case 0:P2 = (P2 & 0x1f) | 0x00;break;//所有锁存器不选择	}P2 = (P2 & 0x1f) | 0x00;//所有锁存器不选择}//3.数码管安位操作void SMG_DisplayBit(unsigned char pos,unsigned char dat){P0 = (0x01 << pos); //数码管的段位	Init_74HC138(6);	P0 = dat;//数码管显示内容	Init_74HC138(7);}//4.操作所有数码管void SMG_All(unsigned char dat){P0 = 0xff;//数码管的段位	Init_74HC138(6);	P0 = dat;//数码管显示内容	Init_74HC138(7);}//5.系统初始化void Init_System(void){P0 = 0xff;//关闭所有led	Init_74HC138(4);	P0 = 0x00;//关闭蜂鸣器和继电器	Init_74HC138(5);	SMG_All(0xff); //关闭所有数码管}//6.数码管数据显示void SMG_Display_Data(void){	SMG_DisplayBit(0,smg_data[value1]);	delay(200);	SMG_DisplayBit(1,0xff);	delay(200);	SMG_DisplayBit(2,0xff);	delay(200);	SMG_DisplayBit(3,0xff);	delay(200);	SMG_DisplayBit(4,0xff);	delay(200);	SMG_DisplayBit(5,0xff);	delay(200);	SMG_DisplayBit(6,smg_data[value2/10]);	delay(200);	SMG_DisplayBit(7,smg_data[value2%10]);	delay(200);	SMG_All(0xff);	delay(200);	}//7.led操作void Led_Tackle(void){led_stat &= ~0x80;//led8电亮	P0 = led_stat;	Init_74HC138(4);	Delay_s(200);	led_stat |= 0x80;//熄灭	P0 = led_stat;	Init_74HC138(4);	Delay_s(200);	value2++;	if(value2 == 100)	{value2 = 0;	}	//led1 和led2 灯同时翻转	if((led_stat & 0x03) == 0x03)	{led_stat &= ~0x03;	}	else	{led_stat |= 0x03;	}	P0 = led_stat;	Init_74HC138(4);	value1++;	if(value1 > 9)	{value1 = 0;	} }void main(void){	Init_System();	while(1)	{Led_Tackle();SMG_Display_Data();}}

注意

在这个代码中需要我们注意的是，在进行led操作函数中我们进行延时的时候也要进行数码管的刷新显示，第一次写就只是简单延时没有进行数码管的刷新显示，结果就是数码管一直在跳led没有闪烁变化，在延时函数中加上数码管动态显示后就可以了。

二、24C02基本读写操作

#include "reg52.h"#include "iic.h"unsigned char dat1,dat2,dat3;unsigned char code smg_data[] = {0xC0,0xF9,0xA4,0xB0,0x99,0x92,0x82,0xF8, 0x80,0x90};//1.简单延时void delay(unsigned int t){while(t--);}//2.锁存器操作void Init_74HC138(unsigned char 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;	}	P2 = (P2 & 0x1f) | 0x00;}//3.数码管安位操作void SMG_DisplayBit(unsigned char pos,unsigned char dat){	P0 = (0x01 << pos);	Init_74HC138(6);	P0 = dat;	Init_74HC138(7);}//关闭所有数码管void SMG_Close(void){P0 = 0xff;	Init_74HC138(6);	P0 = 0xff;	Init_74HC138(7);}//4.系统初始化void Init_System(void){	Init_74HC138(0);P0 = 0x00;	Init_74HC138(5);	P0 = 0xff;	Init_74HC138(4);}//5.数码管数据显示void SMG_Display_Data(void){SMG_DisplayBit(0,smg_data[dat1/10]);	delay(200);	SMG_DisplayBit(1,smg_data[dat1%10]);	delay(200);	SMG_DisplayBit(2,0xbf);	delay(200);	SMG_DisplayBit(3,smg_data[dat2/10]);	delay(200);	SMG_DisplayBit(4,smg_data[dat2%10]);	delay(200);	SMG_DisplayBit(5,0xbf);	delay(200);	SMG_DisplayBit(6,smg_data[dat3/10]);	delay(200);	SMG_DisplayBit(7,smg_data[dat3%10]);	delay(200);	SMG_Close();	delay(200);}//6.at24c02数据写void AT24C02_Write(unsigned char addr,unsigned char dat){IIC_Start();//起始信号	IIC_SendByte(0xa0);//EEPROM的写设备地址	IIC_WaitAck();//等待从机应答	IIC_SendByte(addr);//内存单元地址	IIC_WaitAck();//等待从机应答	IIC_SendByte(dat);//内存写入数据	IIC_WaitAck();//等待从机应答	IIC_Stop();//停止信号}//7.at24c02数据读unsigned char AT24C02_Read(unsigned char addr){unsigned char tmp = 0;//首先 ， 进行一个伪写操作IIC_Start();//起始信号IIC_SendByte(0xa0);//EEPROM的写设备地址IIC_WaitAck();//等待从机应答IIC_SendByte(addr);//内存单元地址IIC_WaitAck();//等待从机应答//然后 ， 开始字节读操作IIC_Start();//起始信号IIC_SendByte(0xa1);//EEPROM的读设备地址IIC_WaitAck();//等待从机应答tmp = IIC_RecByte();//读取内存中的数据IIC_SendAck(1);//产生非应答信号IIC_Stop();//停止信号return tmp;}//8.数据处理void Read_Write_Data(void){//先读取数据	dat1 =AT24C02_Read(0x01);	dat2 =AT24C02_Read(0x03);	dat3 =AT24C02_Read(0x05);	dat1= dat1 +1;	dat2= dat2 +2;	dat3= dat3 + 3 ;	if( dat1 > 10)	{dat1 = 0;	}	if(dat2> 20)	{dat2 = 0;	}	if(dat3> 30)	{dat3 = 0;	}	//将数据写回去	AT24C02_Write(0x01,dat1);	delay(1000);	AT24C02_Write(0x03,dat2);	delay(1000);	AT24C02_Write(0x05,dat3);	delay(1000);}void main(void){Init_System();	Read_Write_Data();	while(1)	{SMG_Display_Data();	}}

三、24C02存储按键触发次数

#include "iic.h"#include "reg52.h"sbit S6 = P3^1;sbit S5 = P3^2;sbit S4 = P3^3;unsigned char s4_value = https://tazarkount.com/read/0,s5_value = 0,s6_value = 0;unsigned char code smg_data[] = {0xC0,0xF9,0xA4,0xB0,0x99,0x92,0x82,0xF8, 0x80,0x90};//1.简单延时void delay(unsigned int t){while(t--);}//2.锁存器初始化void Init_74HC138(unsigned char channel){switch(channel)	{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;	}	P2 = (P2 & 0x1f) | 0x00;}//3.数码管安位操作void SMG_DisplayBit(unsigned char pos,unsigned char dat){P0 = (0x01 << pos);	Init_74HC138(6);	P0 = dat;	Init_74HC138(7);}//4.操作所有数码管void SMG_All(unsigned char dat){P0 = 0xff;	Init_74HC138(6);	P0 = dat;	Init_74HC138(7);}//5.系统初始化void Init_System(void){P0 = 0xff;	Init_74HC138(4);	P0 = 0x00;	Init_74HC138(5);	SMG_All(0xff);}//6.数码管显示数据void SMG_Display_Data(void){SMG_DisplayBit(0,smg_data[s4_value/10]);	delay(200);	SMG_DisplayBit(1,smg_data[s4_value%10]);	delay(200);	SMG_DisplayBit(2,0xbf);	delay(200);	SMG_DisplayBit(3,smg_data[s5_value/10]);	delay(200);	SMG_DisplayBit(4,smg_data[s5_value%10]);	delay(200);	SMG_DisplayBit(5,0xbf);	delay(200);	SMG_DisplayBit(6,smg_data[s6_value/10]);	delay(200);	SMG_DisplayBit(7,smg_data[s6_value%10]);	delay(200);	SMG_All(0xff);	delay(200);}//7.at24c02写数据void AT24C02_Write(unsigned char addr,unsigned char dat){IIC_Start();	IIC_SendByte(0x90);	IIC_WaitAck();	IIC_SendByte(addr);	IIC_WaitAck();	IIC_SendByte(dat);	IIC_WaitAck();	IIC_Stop();}//8.at24c04读数据unsigned char AT24C02_Read(unsigned char addr){	unsigned char temp = 0;	IIC_Start();	IIC_SendByte(0x90);	IIC_WaitAck();	IIC_SendByte(addr);	IIC_WaitAck();	IIC_Start();	IIC_SendByte(0x91);	IIC_WaitAck();	temp = IIC_RecByte();	IIC_SendAck(1);	IIC_Stop();	return temp;}//9.系统上电后 ， 先从24C04存储器的0x00、0x01和0x02这三个地址单元读取数据void AT24C02_Data_Init(void){s4_value =AT24C02_Read(0x00);	delay(1000);	s5_value =AT24C02_Read(0x01);	delay(1000);	s6_value =AT24C02_Read(0x02);	delay(1000);}//10.按键控制void Key_Scans(void){ if(S4 == 0) {delay(20);if(S4 == 0){while(S4 == 0);s4_value++;if(s4_value> 13){s4_value = https://tazarkount.com/read/0;}AT24C02_Write(0x00,s4_value);} }if(S5 == 0) {delay(20);if(S5 == 0){while(S5 == 0);s5_value++;if(s5_value> 13){s5_value = https://tazarkount.com/read/0;}AT24C02_Write(0x01,s5_value);}}if(S6 == 0) {delay(20);if(S6 == 0){while(S6 == 0);s6_value++;if(s6_value> 13){s6_value = https://tazarkount.com/read/0;}AT24C02_Write(0x02,s6_value);} }}void main(void){	Init_System();	AT24C02_Data_Init();	while(1)	{SMG_Display_Data() ;Key_Scans();	}}

四、采样可变电阻电压与光敏电阻电压

#include "iic.h"#include "reg52.h"sbit S4 = P3^3;unsigned char channel = 1;unsigned int adc_value = https://tazarkount.com/read/0,adc_volt = 0;unsigned char code smg_data[] = {0xC0,0xF9,0xA4,0xB0,0x99,0x92,0x82,0xF8, 0x80,0x90};unsigned char code smg_dot[] ={0x40,0x79,0x24,0x30,0x19,0x12,0x02,0x78,0x00,0x10};//1.简单延时void delay(unsigned int t){while(t--);}//2.锁存器初始化void Init_74HC138(unsigned char channel){switch(channel)	{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;	}P2 = (P2 & 0x1f) | 0x00;}//数码管安位操作void SMG_DisplayBit(unsigned char pos,unsigned char dat){P0 = (0x01 << pos);	Init_74HC138(6);	P0 = dat;	Init_74HC138(7);}//操作所有数码管void SMG_All(unsigned char dat){P0 = 0xff;	Init_74HC138(6);	P0 = dat;	Init_74HC138(7);}//系统初始化void Init_System(void){P0 = 0xff;	Init_74HC138(4);	P0 = 0x00;	Init_74HC138(5);	SMG_All(0xff);}//数码管数据显示void SMG_Display_Data(void){SMG_DisplayBit(0,0xbf);	delay(200);	SMG_DisplayBit(1,smg_data[channel]);	delay(200);	SMG_DisplayBit(2,0xbf);	delay(200);	SMG_DisplayBit(3,0xff);	delay(200);	SMG_DisplayBit(4,0xff);	delay(200);	SMG_DisplayBit(5,smg_dot[adc_volt/100]);	delay(200);	SMG_DisplayBit(6,smg_data[adc_volt/10%10]);	delay(200);	SMG_DisplayBit(7,smg_data[adc_volt%10]);	delay(200);	SMG_All(0xff);	delay(200);}//PCF8591数据读取void PCF8591_Read_Data(unsigned char channel){	IIC_Start();	IIC_SendByte(0x90);	IIC_WaitAck();	if(channel == 1)	{IIC_SendByte(0x01);}	else if(channel == 3)	{IIC_SendByte(0x03);}	IIC_WaitAck();	IIC_Stop();	IIC_Start();	IIC_SendByte(0x91);	IIC_WaitAck();	adc_value = IIC_RecByte();	IIC_SendAck(1);	IIC_Stop();	adc_volt = adc_value * (5.0/255)*100;//扩大100倍方便显示}//按键操作void Key_Tackle(void){if(S4 == 0)	{delay(20);if(S4 == 0){while(S4 == 0){if(channel == 1){channel = 3;}else if(channel == 3){channel = 1;}PCF8591_Read_Data(channel);SMG_Display_Data();}}	}}//主函数void main(void){Init_System();while(1)	{Key_Tackle();PCF8591_Read_Data(channel);SMG_Display_Data();	}}

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