Ch14 I2C R/W bit

[olivier.cornez@me.com]

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

[Carmine Noviello]

That bit is set internally by the HAL.

[olivier.cornez@me.com]

Ok Thanks.

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

[Carmine Noviello]

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

[olivier.cornez@me.com]

Found it thanks 😉

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

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