We are using a TI AIC audio codec interfacing with the nRF52 over I2S.
The TI codec specifies the following expected clock frequencies for a sample rate of 16KHz and sample width of 16bits:
MCLK: 4.096MHz, BCLK: 1.024MHz, WCLK: 16KHz
Based on the nrf52832 I2S peripheral documentation, the following configuration will produce the closest settings:
mck_setup: NRF_I2S_MCK_32MDIV8 i.e 4MHz
ratio: NRF_I2S_RATIO_256X i.e 256
Therefore, LRCK = 15625 Hz
But, SCK = 2 * SWIDTH * LRCK = 500KHz which is half the required SCK.
Am I making a mistake in these calculations? Is there any way I can double the SCK? The audio coming out is glitchy -- one of the audio channels is noisy and there are periodic clicks.