In one of our recent projects under development, our board(custom) includes the codec ADAU1381. We use the ST MCU STM32F205 and the codec is connected to the MCU over the i2c and i2s interfaces.
As a first step we try to establish the communication over the I2C in order to configure the necessary parameters to the the different registers. Right now we try to test this communication by writing to the clock control register (addr = 0x4000) and reading it back to see if the write and read are working properly. Unfortunately, we read back the value 0 all the time.
The i2c communication seems to be okay, we are using the BEAGLE I2C analyzer to obtain the communication details.
I am not sure if we are missing something, but in my mind at least the first register (clock control) should be accessible upon the power on reset and the initialization have completed.
Any idea or help are welcome.