SmartClassroom/stm32/HARDWARE/IIC/myiic.c

#include "myiic.h"
#include "delay.h"
//////////////////////////////////////////////////////////////////////////////////	 
//<EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>ֻ<EFBFBD><EFBFBD>ѧϰʹ<EFBFBD>ã<EFBFBD>δ<EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>ɣ<EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>κ<EFBFBD><EFBFBD><EFBFBD>;
//ALIENTEK<EFBFBD><EFBFBD>ӢSTM32<EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>
//IIC<EFBFBD><EFBFBD><EFBFBD><EFBFBD> <EFBFBD><EFBFBD><EFBFBD><EFBFBD>	   
//<EFBFBD><EFBFBD><EFBFBD><EFBFBD>ԭ<EFBFBD><EFBFBD>@ALIENTEK
//<EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>̳:www.openedv.com
//<EFBFBD>޸<EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>:2012/9/9
//<EFBFBD>汾<EFBFBD><EFBFBD>V1.0
//<EFBFBD><EFBFBD>Ȩ<EFBFBD><EFBFBD><EFBFBD>У<EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>ؾ<EFBFBD><EFBFBD><EFBFBD>
//Copyright(C) <EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>ӿƼ<EFBFBD><EFBFBD><EFBFBD><EFBFBD>޹<EFBFBD>˾ 2009-2019
//All rights reserved									  
//////////////////////////////////////////////////////////////////////////////////
 
//<EFBFBD><EFBFBD>ʼ<EFBFBD><EFBFBD>IIC
void MYIIC_Init(void)
{					     
	GPIO_InitTypeDef GPIO_InitStructure;
	RCC_APB2PeriphClockCmd(	RCC_APB2Periph_GPIOC, ENABLE );	//ʹ<EFBFBD><EFBFBD>GPIOBʱ<EFBFBD><EFBFBD>
	   
	GPIO_InitStructure.GPIO_Pin = GPIO_Pin_14|GPIO_Pin_13;
	GPIO_InitStructure.GPIO_Mode = GPIO_Mode_Out_PP ;   //<EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>
	GPIO_InitStructure.GPIO_Speed = GPIO_Speed_50MHz;
	GPIO_Init(GPIOC, &GPIO_InitStructure);
	GPIO_SetBits(GPIOC,GPIO_Pin_14|GPIO_Pin_13); 	
}

//<EFBFBD><EFBFBD><EFBFBD><EFBFBD>IIC<EFBFBD><EFBFBD>ʼ<EFBFBD>ź<EFBFBD>
void MYIIC_Start(void)
{
	SDA_OUT();     //sda<EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>
	IIC_SDA=1;	  	  
	IIC_SCL=1;
	delay_us(4);
 	IIC_SDA=0;//START:when CLK is high,DATA change form high to low 
	delay_us(4);
	IIC_SCL=0;//ǯסI2C<EFBFBD><EFBFBD><EFBFBD>ߣ<EFBFBD>׼<EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>ͻ<EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD> 
}	  
//<EFBFBD><EFBFBD><EFBFBD><EFBFBD>IICֹͣ<EFBFBD>ź<EFBFBD>
void MYIIC_Stop(void)
{
	SDA_OUT();//sda<EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>
	IIC_SCL=0;
	IIC_SDA=0;//STOP:when CLK is high DATA change form low to high
 	delay_us(4);
	IIC_SCL=1; 
	IIC_SDA=1;//<EFBFBD><EFBFBD><EFBFBD><EFBFBD>I2C<EFBFBD><EFBFBD><EFBFBD>߽<EFBFBD><EFBFBD><EFBFBD><EFBFBD>ź<EFBFBD>
	delay_us(4);							   	
}
//<EFBFBD>ȴ<EFBFBD>Ӧ<EFBFBD><EFBFBD><EFBFBD>źŵ<EFBFBD><EFBFBD><EFBFBD>
//<EFBFBD><EFBFBD><EFBFBD><EFBFBD>ֵ<EFBFBD><EFBFBD>1<EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>Ӧ<EFBFBD><EFBFBD>ʧ<EFBFBD><EFBFBD>
//        0<EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>Ӧ<EFBFBD><EFBFBD><EFBFBD>ɹ<EFBFBD>
u8 MYIIC_Wait_Ack(void)
{
	u8 ucErrTime=0;
	SDA_IN();      //SDA<EFBFBD><EFBFBD><EFBFBD><EFBFBD>Ϊ<EFBFBD><EFBFBD><EFBFBD><EFBFBD>  
	IIC_SDA=1;delay_us(1);	   
	IIC_SCL=1;delay_us(1);	 
	while(READ_SDA)
	{
		ucErrTime++;
		if(ucErrTime>250)
		{
			MYIIC_Stop();
			return 1;
		}
	}
	IIC_SCL=0;//ʱ<EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>0 	   
	return 0;  
} 
//<EFBFBD><EFBFBD><EFBFBD><EFBFBD>ACKӦ<EFBFBD><EFBFBD>
void IIC_Ack(void)
{
	IIC_SCL=0;
	SDA_OUT();
	IIC_SDA=0;
	delay_us(2);
	IIC_SCL=1;
	delay_us(2);
	IIC_SCL=0;
}
//<EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>ACKӦ<EFBFBD><EFBFBD>		    
void IIC_NAck(void)
{
	IIC_SCL=0;
	SDA_OUT();
	IIC_SDA=1;
	delay_us(2);
	IIC_SCL=1;
	delay_us(2);
	IIC_SCL=0;
}					 				     
//IIC<EFBFBD><EFBFBD><EFBFBD><EFBFBD>һ<EFBFBD><EFBFBD><EFBFBD>ֽ<EFBFBD>
//<EFBFBD><EFBFBD><EFBFBD>شӻ<EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>Ӧ<EFBFBD><EFBFBD>
//1<EFBFBD><EFBFBD><EFBFBD><EFBFBD>Ӧ<EFBFBD><EFBFBD>
//0<EFBFBD><EFBFBD><EFBFBD><EFBFBD>Ӧ<EFBFBD><EFBFBD>			  
void IIC_Send_Byte(u8 txd)
{                        
    u8 t;   
	SDA_OUT(); 	    
    IIC_SCL=0;//<EFBFBD><EFBFBD><EFBFBD><EFBFBD>ʱ<EFBFBD>ӿ<EFBFBD>ʼ<EFBFBD><EFBFBD><EFBFBD>ݴ<EFBFBD><EFBFBD><EFBFBD>
    for(t=0;t<8;t++)
    {              
        IIC_SDA=(txd&0x80)>>7;
        txd<<=1; 	  
		delay_us(2);   //<EFBFBD><EFBFBD>TEA5767<EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>ʱ<EFBFBD><EFBFBD><EFBFBD>DZ<EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>
		IIC_SCL=1;
		delay_us(2); 
		IIC_SCL=0;	
		delay_us(2);
    }	 
} 	    
//<EFBFBD><EFBFBD>1<EFBFBD><EFBFBD><EFBFBD>ֽڣ<EFBFBD>ack=1ʱ<EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>ACK<EFBFBD><EFBFBD>ack=0<EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>nACK   
u8 IIC_Read_Byte(unsigned char ack)
{
	unsigned char i,receive=0;
	SDA_IN();//SDA<EFBFBD><EFBFBD><EFBFBD><EFBFBD>Ϊ<EFBFBD><EFBFBD><EFBFBD><EFBFBD>
    for(i=0;i<8;i++ )
	{
        IIC_SCL=0; 
        delay_us(2);
		IIC_SCL=1;
        receive<<=1;
        if(READ_SDA)receive++;   
		delay_us(1); 
    }					 
    if (!ack)
        IIC_NAck();//<EFBFBD><EFBFBD><EFBFBD><EFBFBD>nACK
    else
        IIC_Ack(); //<EFBFBD><EFBFBD><EFBFBD><EFBFBD>ACK   
    return receive;
}