一、硬件电路：

1、引脚功能：

（1）A0-A2：决定不同设备的地址码：

（2）WP：写保护

二、通讯方式（IIC协议）

通讯方式与PCF8591相同，可参考以下文章：

蓝桥杯模块学习16——PCF8591（深夜学习——单片机）_佛科院深夜学习的博客-CSDN博客

1、设备地址：

由于我们使用的02型号的所以是2K的

2、按地址读取

先写入读取地址再进行读取

3、连续写或读操作：

我们只需在写或读完数据字节后发送应答信号（“1”），就能进行连续读或写，2K EEPROM最多可以连续读写8个字节

三、AT24C02实验：

1、代码思路：

定时器1，数码管——》读取AT24C02——》写入AT24C02——》满足实验要求

2、参考代码：

由于题目表达不清晰，我以为是一直循环：将数据+1、+2、+3，再往内存单元中写入，所以给自己增加难度了，如果你想挑战自己可以尝试一下，如果不想可以参考一下文章：

(5条消息) 【蓝桥杯单片机进阶强化-03】24C02存储器的基本原理与应用_小蜜蜂老师的博客-CSDN博客

（1）IIC代码：

#ifndef _IIC_H
#define _IIC_H#include <STC15F2K60S2.H>
#include "intrins.h"
#define u8 unsigned char
#define u16 unsigned int    sbit SDA = P2^1;
sbit SCL = P2^0;void IIC_Start(void); 
void IIC_Stop(void);  
bit IIC_WaitAck(void);  
void IIC_SendAck(bit ackbit); 
void IIC_SendByte(unsigned char byt); 
unsigned char IIC_RecByte(void); 
u8 AT24C02_Read_one(u8 adr);
void AT24C02_Write_one(u8 adr,u8 w_dat);
#endif

#include "iic.h"#define DELAY_TIME 5//
void IIC_Delay(unsigned char i)
{ do{_nop_();}while(i--);     
}//
void IIC_Start(void)
{SDA = 1;SCL = 1;IIC_Delay(DELAY_TIME);SDA = 0;IIC_Delay(DELAY_TIME);SCL = 0;    
}//
void IIC_Stop(void)
{SDA = 0;SCL = 1;IIC_Delay(DELAY_TIME);SDA = 1;IIC_Delay(DELAY_TIME);
}//
void IIC_SendAck(bit ackbit)
{SCL = 0;SDA = ackbit;                      IIC_Delay(DELAY_TIME);SCL = 1;IIC_Delay(DELAY_TIME);SCL = 0; SDA = 1;IIC_Delay(DELAY_TIME);
}//
bit IIC_WaitAck(void)
{bit ackbit;SCL  = 1;IIC_Delay(DELAY_TIME);ackbit = SDA;SCL = 0;IIC_Delay(DELAY_TIME);return ackbit;
}//
void IIC_SendByte(unsigned char byt)
{unsigned char i;for(i=0; i<8; i++){SCL  = 0;IIC_Delay(DELAY_TIME);if(byt & 0x80) SDA  = 1;else SDA  = 0;IIC_Delay(DELAY_TIME);SCL = 1;byt <<= 1;IIC_Delay(DELAY_TIME);}SCL  = 0;  
}//
unsigned char IIC_RecByte(void)
{unsigned char i, da;for(i=0; i<8; i++){   SCL = 1;IIC_Delay(DELAY_TIME);da <<= 1;if(SDA) da |= 1;SCL = 0;IIC_Delay(DELAY_TIME);}return da;    
}u8 AT24C02_Read_one(u8 adr)
{u8 r_dat;IIC_Start();IIC_SendByte(0xa0);IIC_WaitAck();IIC_SendByte(adr);IIC_WaitAck();IIC_Start();IIC_SendByte(0xa1);IIC_WaitAck();r_dat = IIC_RecByte();IIC_SendAck(1);IIC_Stop();return r_dat;
}void AT24C02_Write_one(u8 adr,u8 w_dat)
{IIC_Start();IIC_SendByte(0xa0);IIC_WaitAck();IIC_SendByte(adr);IIC_WaitAck();IIC_SendByte(w_dat);IIC_WaitAck();IIC_Stop();
}

（2）主函数：（我使用了一些非抢占式分配的思路，如果看不懂可以就看上面的那篇文章就行）

#include <STC15F2K60S2.H>
#include <stdio.H>
#include "iic.h"
#define u8 unsigned char
#define u16 unsigned int    
code unsigned char Seg_Table[] = 
{
0xc0, //0
0xf9, //1
0xa4, //2
0xb0, //3
0x99, //4
0x92, //5
0x82, //6
0xf8, //7
0x80, //8
0x90, //9
0x88, //A
0x83, //b
0xc6, //C
0xa1, //d
0x86, //E
0x8e //F
};//数码管
u8 COD[8],COT[9],PSI;
u16 seg_delay;
//AT24C02
u8 at24_dat[5],show_dat[3];
u16 cout_11ms;
u16 AT24_dealy[3]={0,1,1};
u8 show_delay;
u16 ms_count;
void Close_All();
void Timer1_Init(void);
void SEG_Rroc();
void AT24C02_Proc();
void SEG_Show_Rroc();
void AT24C02_Read_Proc();
void AT24C02_Plus_Proc();
void AT24C02_Write_Proc();
void main()
{Close_All();Timer1_Init();while(1){SEG_Rroc();SEG_Show_Rroc();AT24C02_Read_Proc();AT24C02_Plus_Proc();AT24C02_Write_Proc();}
}/**************定时器******************/
void SEG_Show(u8 COD,u8 PSI);
void Timer1_Isr(void) interrupt 3
{ms_count++;if(ms_count == seg_delay) seg_delay = 0;if(ms_count % 2 == 0)  show_delay = 0;if(ms_count == AT24_dealy[0])  AT24_dealy[0] = 0;if(ms_count ==  AT24_dealy[1])  AT24_dealy[1] = 0;if(ms_count == AT24_dealy[2])  AT24_dealy[2] = 0;if(ms_count == 1000) ms_count = 0;
}void Timer1_Init(void)        //1毫秒@12.000MHz
{AUXR &= 0xBF;            //定时器时钟12T模式TMOD &= 0x0F;            //设置定时器模式TL1 = 0x18;                //设置定时初始值TH1 = 0xFC;                //设置定时初始值TF1 = 0;                //清除TF1标志TR1 = 1;                //定时器1开始计时ET1 = 1;                //使能定时器1中断EA = 1;
}/*************数码管*******************/
void SEG_TSL(u8* input,u8* output)
{u8 i;for(i=0;i<8;i++){switch(input[i]){case '0':output[i] = Seg_Table[0];break;case '1':output[i] = Seg_Table[1];break;case '2':output[i] = Seg_Table[2];break;case '3':output[i] = Seg_Table[3];break;case '4':output[i] = Seg_Table[4];break;case '5':output[i] = Seg_Table[5];break;case '6':output[i] = Seg_Table[6];break;case '7':output[i] = Seg_Table[7];break;case '8':output[i] = Seg_Table[8];break;case '9':output[i] = Seg_Table[9];break;case '-':output[i] = ~0x40;break;default:output[i] = 0xff;}}
}void SEG_Show(u8 COD,u8 PSI)
{//消隐P0 = 0xff;P2 = P2 & 0x1f | (0x70<<1);P2 &= 0x1f;//位选P0 = 0x01<<PSI;P2 = P2 & 0x1f | (0x60<<1);P2 &= 0x1f;//段选P0 = COD;P2 = P2 & 0x1f | (0x70<<1);P2 &= 0x1f;
}
/**************************************/
/*关闭无关设备
*/
void Close_All()
{//关闭蜂鸣器和继电器P0 = 0x00;P2 = P2 & 0x1f | (0x50<<1);P2 &= 0x1f;//关闭LEDP0 = 0xff;P2 = P2 & 0x1f | (0x40<<1);P2 &= 0x1f;    
}void SEG_Rroc()
{if(seg_delay)return;seg_delay = 997;sprintf(COT,"%02u-%02u-%02u",(u16)show_dat[0],(u16)show_dat[1],(u16)show_dat[2]);SEG_TSL(COT,COD);
}void SEG_Show_Rroc()
{if(show_delay)return;show_delay = 1;SEG_Show(COD[PSI],PSI);if(PSI++ == 7)PSI = 0;
}
void AT24C02_Read_Proc()
{static r_num=0;if(AT24_dealy[0])return;AT24_dealy[0] = 499;AT24_dealy[0] += 10*(r_num+1);EA = 0;at24_dat[r_num] = AT24C02_Read_one(0x01+2*r_num);show_dat[r_num] = at24_dat[r_num];EA = 1;if(r_num++ == 2)r_num = 0;
}void AT24C02_Plus_Proc()
{if(AT24_dealy[1])return;AT24_dealy[1] = 599;at24_dat[0] +=1;at24_dat[1] +=2;at24_dat[2] +=3;if(at24_dat[0] > 10)at24_dat[0] = 0;if(at24_dat[1] > 20)at24_dat[1] = 0;if(at24_dat[2] > 30)at24_dat[2] = 0;    
}
void AT24C02_Write_Proc()
{static w_num=0;if(AT24_dealy[2])return;AT24_dealy[2] = 699;AT24_dealy[2] += 4*(w_num+1);EA = 0;AT24C02_Write_one(0x01+2*w_num,at24_dat[w_num]);EA = 1;if(w_num++ == 2)w_num = 0;
}