通过本程序设计，对IIC时序有了更深刻的理解

#include <STC15F2K60S2.H>
#include "INit.h"
#include "LED.h"
#include "smg.h"
#include "Key.h"
#include "iic.h"
unsigned char key_slow_down;
unsigned char key_old,key_val,key_down,key_up;
unsigned int smg_slow_down;
unsigned char smg_pos;
unsigned char smg_buf[8] = {11,11,11,11,11,11,11,11};
unsigned char smg_point[8] = {0,0,0,0,0,0,0,0};
unsigned char led_buf[8] = {0,0,0,0,0,0,0,0};
float Voltage,Voltage_output;

bit smg_mode;
bit smg_flag = 1;
bit output_mode;

void Key_Function()
{
	if(key_slow_down)return;
	key_slow_down = 1;
	key_val = Key_Get();
	key_down =  key_val & (key_val ^ key_old);
	key_up = ~key_val & (key_val ^ key_old);
	key_old = key_val;
	
	if(key_down==4){
		smg_mode ^=1;
	}
	if(smg_mode==1){
		if(key_down==5)output_mode ^=1;
	}
	if(key_down==7){
		smg_flag ^=1;
	}
	
}
void smg_Function()
{
	if(smg_slow_down)return;
	smg_slow_down = 1;
	Voltage = Ad_Read(0x43)/51.0;
	
	if(smg_mode ==0)
	{
		smg_buf[0]= 12;
		smg_buf[5]= (unsigned int)(Voltage *100) /100 %10;
		smg_buf[6]= (unsigned int)(Voltage *100) /10  %10;
		smg_buf[7]= (unsigned int)(Voltage *100)     %10;
		smg_point[5] = 1;
	}
	else
	{
		if(output_mode==0){
			Voltage_output=2.0;
		}
		else{
			Voltage_output = Voltage;
		}
		smg_buf[0]= 13;
		smg_buf[5]= (unsigned int)(Voltage_output *100) /100 %10;
		smg_buf[6]= (unsigned int)(Voltage_output *100) /10  %10;
		smg_buf[7]= (unsigned int)(Voltage_output *100)     %10;
		smg_point[5] = 1;
	}
	
}

void LED_Function()
{
	//Da_Write(Voltage_output*51);
	unsigned char i=0;
	for(i=0;i<2;i++)
	{
		led_buf[i] = (i == smg_mode);
		
	}
	if(Voltage<1.5 || Voltage>=2.5 && Voltage<3.5){
		led_buf[2] = 0;
	}
	else{
		led_buf[2] = 1;
	}
	led_buf[3] = output_mode;
}
void Timer0_Init(void)		//1毫秒@12.000MHz
{
	AUXR &= 0x7F;			//定时器时钟12T模式
	TMOD &= 0xF0;			//设置定时器模式
	TL0 = 0x18;				//设置定时初始值
	TH0 = 0xFC;				//设置定时初始值
	TF0 = 0;				//清除TF0标志
	TR0 = 1;				//定时器0开始计时
	
	ET0 = 1;
	EA=1;
}

void Timer0_Function() interrupt 1
{
	if(++key_slow_down==25)key_slow_down=0;
	if(++smg_slow_down==50)smg_slow_down=0;
	if(++smg_pos==8)smg_pos = 0;
	if(smg_flag==1){
		Smg_Set(smg_pos,smg_buf[smg_pos],smg_point[smg_pos]);
	}
	else{
		Smg_Set(smg_pos,11,0);
	}
	
	LED_Set(smg_pos,led_buf[smg_pos]);
}
void main()
{
	System_Init();
	Timer0_Init();
	while(1)
	{
		Key_Function();
		smg_Function();
		LED_Function();
	}
}