24c64工作子程序.c

这是我测试存储芯片24C64的程序

/*24C64子程序 */
bit   I2C_Start(void);
void  I2C_Stop(void);
void  I2C_Ack(void);
void  I2C_Nack(void);
bit   I2C_Send_Byte( uchar);
void  AT24C64_R(void *mcu_address,uint AT24C64_address,uint count);
void  AT24C64_W(void *mcu_address,uint AT24C64_address,uint count);

void  Delay_10_uS(void)//延时10uS
{
	 char i=10;
	 while(i--);
}

void Delay_N_mS( uint n_milisecond)  // n mS delay 毫秒级延时
{
	 uchar i;
	 while(n_milisecond--)
	 {
	  i=37;
	  while(i--);
	 }
}

bit I2C_Start(void)//启动总线
{
	 Delay_10_uS();
	 I2C_SDA =1;
	 Delay_10_uS();
	 I2C_SCK =1;
	 Delay_10_uS();
	 if ( I2C_SDA == 0) return 0;
	 if ( I2C_SCK == 0) return 0;
	 I2C_SDA = 0;
	 Delay_10_uS();
	 I2C_SCK = 0;
	 Delay_10_uS();
	 return 1;
}

void  I2C_Stop(void)//停止总线
{
	 Delay_10_uS();
	 I2C_SDA = 0;
	 Delay_10_uS();
	 I2C_SCK = 1;
	 Delay_10_uS();
	 I2C_SDA = 1;
	 Delay_10_uS();
}

void I2C_Ack(void)//非应答信号
{
	 Delay_10_uS();
	 I2C_SDA=0;
	 Delay_10_uS();
	 I2C_SCK=1;
	 Delay_10_uS();
	 I2C_SCK=0;
	 Delay_10_uS();
}

void I2C_Nack(void))//是应答信号
{
	 Delay_10_uS();
	 I2C_SDA=1;
	 Delay_10_uS();
	 I2C_SCK=1;
	 Delay_10_uS();
	 I2C_SCK=0;
	 Delay_10_uS();
}

bit I2C_Send_Byte( uchar d)//字节发送
{
		 uchar i = 8;
		 bit bit_ack;
		 while( i-- )
				 {
				  Delay_10_uS();
				  if ( d &0x80 )   I2C_SDA =1;
				  else             I2C_SDA =0;
				  Delay_10_uS();
				  I2C_SCK = 1;
				  Delay_10_uS();
				  I2C_SCK = 0;
				  d = d << 1;
				 }
		 Delay_10_uS();
		 I2C_SDA = 1;
		 Delay_10_uS();
		 I2C_SCK = 1;
		 Delay_10_uS();
		 bit_ack = I2C_SDA;
		 I2C_SCK =0;
		 Delay_10_uS();
		 return bit_ack;
		}
		
uchar I2C_Receive_Byte(void)//字节读
{
			 uchar i = 8, d;
			 Delay_10_uS();
			 I2C_SDA = 1;
			 while ( i--)
				 {
				  d = d << 1;
				  Delay_10_uS();
				  I2C_SCK =1;
				  if ( I2C_SDA ) d++;
				  Delay_10_uS();
				  I2C_SCK =0;
				 }
 return d;
}
//*mcu_address:数据地址指针；uint AT24C64_address：器件存储地址；uint count：数据字节数
void AT24C64_W(void *mcu_address,uint AT24C64_address,uint count)
{
		 DOG_WDI=!DOG_WDI;
		 DOGTIME=0;
		 while(count--)
			 {
				  I2C_Start();
				  I2C_Send_Byte( 0xa0 );//器件写
				  I2C_Send_Byte(  AT24C64_address/256 );// 写入地址高8位分离
				  I2C_Send_Byte( AT24C64_address %256 );//写入地址低8位分离
				  I2C_Send_Byte( *(uchar*)mcu_address );//写入首位数据
				  I2C_Stop();
				  Delay_N_mS(10);       /* waiting for write cycle to be completed */
				  ((uchar*)mcu_address)++;//数据指针加一，指向下一个数据
				  AT24C64_address++;//存入24c64下一个存储位置
			 }
}

void AT24C64_R(void *mcu_address,uint AT24C64_address,uint count)
{
		 DOG_WDI=!DOG_WDI;
		 DOGTIME=0;
		 while(count--)
			 {
			  I2C_Start();
			  I2C_Send_Byte( 0xa0 );//器件写地址
			  I2C_Send_Byte( AT24C64_address/256 );//高8位地址
			  I2C_Send_Byte( AT24C64_address % 256 );//低8位地址
			  I2C_Start();
			  I2C_Send_Byte( 0xa1 );//器件读数据
			  *(uchar*)mcu_address = I2C_Receive_Byte();//读入首位数据存入
			  I2C_Nack();
			  I2C_Stop();
			  ((uchar*)mcu_address)++;//指向下一个地址
			  AT24C64_address++;//准备读器件下一个地址内容
			 }
}