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  • February 8, 2017 at 10:30 am #6085
    olivier.cornez@me.com
    Participant

    Hi,

    I am confused the book mention that the LSB bit of the slave address must be set to 1 for read and 0 for write operation but the code sample calls

    Write_To_24LCxx(&hi2c1, 0xA0, 0x1AAA, (uint8_t*)wmsg, strlen(wmsg)+1);
    Read_From_24LCxx(&hi2c1, 0xA0, 0x1AAA, (uint8_t*)rmsg, strlen(wmsg)+1);

    So twice the same address.
    I do not understand where the R/W bit is changed.

    Could you help to clarify this please?
    Thanks

    February 8, 2017 at 10:33 am #6087
    Carmine Noviello
    Keymaster

    That bit is set internally by the HAL.

    February 8, 2017 at 11:29 am #6089
    olivier.cornez@me.com
    Participant

    Ok Thanks.

    If I debug step by step I should be able to find where in the HAL it is done. Correct?

    February 8, 2017 at 5:34 pm #6105
    Carmine Noviello
    Keymaster

    See to the way the I2C_TransferConfig() is called inside the HAL_I2C_Master_Receive().

    February 12, 2017 at 6:51 pm #6132
    olivier.cornez@me.com
    Participant

    Found it thanks 😉

    hi2c->Instance->DR = I2C_7BIT_ADD_WRITE(DevAddress);

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