蓝桥杯之单片机学习（十九）——IIC协议（PCF8591、AT24C02）

#include "reg52.h"
#include "intrins.h"
#include "iic.h"
typedef unsigned char BYTE;
typedef unsigned int WORD;
unsigned char adc_table[3];
unsigned char volt_table[3];
unsigned char open_num_table[2];
//-----------------------------------------------
/* define constants */
#define FOSC 11059200L
#define T1MS (65536-FOSC/12/1000)   //1ms timer calculation method in 12T mode
/* define SFR */
sbit TEST_LED = P1^0;               //work LED, flash once per second
/* define variables */
WORD count;                         //1000 times counter
//-----------------------------------------------
unsigned char code T_display[]={0x3F,0x06,0x5B,0x4F,0x66,0x6D,0x7D,0x07,0x7F,0x6F};
unsigned char code T_COM[]={0x01,0x02,0x04,0x08,0x10,0x20,0x40,0x80}; 
/* Timer0 interrupt routine */
void tm0_isr() interrupt 1 using 1
{
  static char i;
    TL0 = T1MS;                     //reload timer0 low byte
    TH0 = T1MS >> 8;                //reload timer0 high byte
    if (count-- == 0)               //1ms * 1000 -> 1s
    {
      count = 1;               //reset counter
          P2=0xe0;P0=~open_num_table[i];P2=0;
      P2=0xc0;P0=T_COM[i];P2=0;
      i++;
      if(i==2) i=0;
    }
}
//-----------------------------------------------
void Delay2ms()  //@11.0592MHz
{
  unsigned char i, j;
  _nop_();
  i = 4;
  j = 146;
  do
  {
  while (--j);
  } while (--i);
}
/* main program */
void main()
{
  unsigned char adc_val;
   unsigned char open_num=0;
  float volt;
  open_num =read_24c02(0x55);
  write_24c02(0x55,++open_num);
  open_num_table[0]=T_display[open_num/10];
  open_num_table[1]=T_display[open_num%10];
    TMOD = 0x01;                    //set timer0 as mode1 (16-bit)
    TL0 = T1MS;                     //initial timer0 low byte
    TH0 = T1MS >> 8;                //initial timer0 high byte
    TR0 = 1;                        //timer0 start running
    ET0 = 1;                        //enable timer0 interrupt
    EA = 1;                         //open global interrupt switch
    count = 0;                      //initial counter
  write_adc(0x03); // ch3
  while(1)
  {
  EA=0;
  adc_val=read_adc(0x03);
  EA=1;
  volt=adc_val/255.0f*5;
  adc_table[0]=adc_val/100;//bai
  adc_table[1]=adc_val/10%10;//shi
  adc_table[2]=adc_val%10;
  volt_table[0]=T_display[(unsigned char)volt] | 0x80;
  volt_table[1]=T_display[(unsigned char)(volt*10)%10];
  volt_table[2]=T_display[(unsigned char)(volt*100)%10];
  Delay2ms();
  }
}