24C64 EEPROM读写的C语言程序
作者： 时间：2009-06-21 23:28 来源：
/*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);
uchar I2C_Receive_Byte(void);
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)
{
char i=10;
while(i--);
}
void Delay_N_mS( uint n_milisecond) /* n mS delay */
{
uchar i;
while(n_milisecond--)
{
i=37;
while(i--);
}
}
bit I2C_Start(void)
{
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)
{
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)
{
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)
{
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)
{
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)
{
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;
}
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 + AT24C64_address /256 *2);*/ /* 24C16 USE */
I2C_Send_Byte( 0xa0 );
I2C_Send_Byte( AT24C64_address/256 );
I2C_Send_Byte( AT24C64_address %256 );
I2C_Send_Byte( *(uchar*)mcu_address );
I2C_Stop();
Delay_N_mS(10); /* waiting for write cycle to be completed */
((uchar*)mcu_address)++;
AT24C64_address++;
}
}
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 + AT24C64_address / 256 *2 );*/ /* 24C16 USE */
I2C_Send_Byte( 0xa0 );
I2C_Send_Byte( AT24C64_address/256 );
I2C_Send_Byte( AT24C64_address % 256 );
I2C_Start();
/*I2C_Send_Byte( 0xa1 + AT24C64_address /256 *2 );*/
I2C_Send_Byte( 0xa1 );
*(uchar*)mcu_address = I2C_Receive_Byte();
I2C_Nack();
I2C_Stop();
((uchar*)mcu_address)++;
AT24C64_address++;
}
}