Prepare Hardware

Follow the steps below to prepare hardware for connecting to external codecs.

1. Make sure hardware connections are correct.
   1. Make sure all the hardware connections are correct, including I2C_SDA, I2C_SCK, I2S_MCLK, I2S_BCLK, I2S_LRCK, I2S_DIN, and I2S_DOUT, all the clock and data pins are confirmed as working properly.
   2. Make sure the I2S module of the SoC and the external codec modules are fed with the proper power supply.
2. Make sure you have checked the hardware schematics. And by checking the schematics, all the following items are correct.
   1. Confirm that the target I2S and the corresponding pins and pin multiplexing are working properly.
   2. Confirm that the I2C used for communication between the external codec and SoC is working properly.
3. Make sure you have checked the datasheet of the external codec. And by checking the datasheet, confirm all the following items are correct.
   1. Confirm the required work mode is master mode or slave mode.
   2. Confirm that the mclk, sysclk, bclk and lrclk are derived from sysclk.
   3. Confirm the supported sample rate range.
   4. Confirm the clock polarity.
   5. Confirm the data format. (For sample bit width, Left justified, Right justified, I2S, and DSP mode).
   6. Confirm the I2C address of the external codec.