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ST7 S/W IMPLEMENTATION OF I2C BUS MASTER

{

count=0;

I2C_SR1=0;

I2C_SR2=0;

I2C_DR=0;

err_status=0;

t_count_err=0;

r_count_err=0;

SetBit(I2C_SR1,M_SL);

/* Master mode: M_SL=1

*/

}

/*--------------------------------------------------------------------------

ROUTINE NAME : I2Cm_TxData

INPUT/OUTPUT : data byte to be transfered(MSB first) / None.

DESCRIPTION : Transmits a data bit.

COMMENTS

: Transfer sequence = DATA, ACK, ...

--------------------------------------------------------------------------*/

void I2Cm_TxData (void)

{

SetBit(PADDR,SCL);

/* Low level on SCL

*/

if (I2C_SR2)

/* Check the communication error status */

{

err_status++;

t_count_err++;

if (t_count_err==0) t_count_err++;

}

else

/* If no error

*/

{

if (ValBit(I2C_DR,7))

/* Send data bit per bit, MSB first

*/

SetBit(PADR,SDA);

/* Send a one

*/

else

ClrBit(PADR,SDA);

/* Send a zero

*/

I2C_DR*=2;

ClrBit(PADDR,SCL);

/* High state on SCL

*/

delay(10);

}

}

/*--------------------------------------------------------------------------

ROUTINE NAME : I2Cm_RxData

INPUT/OUTPUT : Last byte to receive flag (active high) / Received data bit.

DESCRIPTION : Receive a data byte.

COMMENTS

: Transfer sequence = DATA, ACK, EV7...

--------------------------------------------------------------------------*/

void I2Cm_RxData (void)