基于单片机的秒表程序上读写数据至24c02芯片

只看该作者 · 2016-6-15 22:18

      #include<reg51.h>
            #define uchar unsigned char
            #define uint unsigned int

            bit write=0;
            sbit sda=P2^0;
            sbit scl=P2^1;
            sbit wei0=P1^0;
            sbit wei1=P1^1;
            uchar sec,tcnt;
            uchar code table[]={0xc0,0xf9,0xa4,0xb0,0x99,0x92,0x82,0xf8,0x80,0x90};
            void delay()
            { ; ; }
            void delayms(uint z)
            {
                     uint x,y;
                     for(x=z;x>0;x--)
                     for(y=110;y>0;y--);

            }
            void start()
            {
                     sda=1;
                     delay();
                     scl=1;
                     delay();
                     sda=0;
                     delay();
            }
            void stop()
            {
                     sda=0;
                     delay();
                     scl=1;
                     delay();
                     sda=1;
                     delay();
            }
            void respons()
            {
                     uchar i;
                     scl=1;
                     delay();
                     while((sda==1)&&(i<250))i++;
                     scl=0;
                     delay();
            }
            void init()
            {
                     sda=1;
                     delay();
                     scl=1;
                     delay();
            }
            void write_byte(uchar date)
            {
                     uchar i,temp;
                     temp=date;
                     for(i=0;i<8;i++)
                     {
                              temp=temp<<1;
                              scl=0;
                              delay();
                              sda=CY;
                              delay();
                              scl=1;
                              delay();
                     }
                     scl=0;
                     delay();
                     sda=1;
                     delay();
            }
            uchar read_byte()
            {
                     uchar i,k;
                     scl=0;
                     delay();
                     sda=1;
                     delay();
                     for(i=0;i<8;i++)
                     {
                              scl=1;
                              delay();
                              k=(k<<1)|sda;
                              scl=0;
                              delay();
                     }
                  return k;
            }
            void write_add(uchar address,uchar date)
            {
                     start();
                     write_byte(0xa0);
                     respons();
                     write_byte(address);
                     respons();
                     write_byte(date);
                     respons();
                     stop();
            }
            uchar read_add(uchar address)
            {
                     uchar date;
                     start();
                     write_byte(0xa0);
                     respons();
                     write_byte(address);
                     respons();
                     start();
                     write_byte(0xa1);
                     respons();
                     date=read_byte();
                     stop();
                     return date;

            }
            void display(uchar shi,uchar ge)
            {

                     wei0=1;
                     wei1=1;
                     P0=table[shi];
                     wei0=0;
                     delayms(10);
                     wei0=1;
                     wei1=0;
                     P0=table[ge];
                     delayms(10);
                     wei1=1;
            }
            void main()
            {
                     init();
                     sec=read_add(2);
                     if(sec>100)sec=0;
                     TMOD=0x01;
                     ET0=1;
                     EA=1;
                     TH0=(65536-50000)/256;
                     TL0=(65536-50000)%256;
                     TR0=1;
                     while(1)
                     {
                              display(sec/10,sec%10);
                              if(write==1)
                              {
                                    write=0;
                                    write_add(2,sec);
                              }
                     }
            }
            void t0() interrupt 1
            {
                     TH0=(65536-50000)/256;
                     TL0=(65536-50000)%256;
                     tcnt++;
                     if(tcnt==20)
                     {
                              tcnt=0;
                              sec++;
                              write=1;
                              if(sec==100)
                              sec=0;
                     }
            }