On Sun, Jun 19, 2016 at 05:46:02PM -0400, Rob Calhoun wrote:
Hi Matt,
Based on my experience with the WM8737, the bitclock will always run at 12 MHz on these devices in USB mode. While the carrying capacity of the channel is always 12 Mbps, the data put on the wire by the codec depend on the sample rate, number of channels, and bit depth. This leaves some unused capacity in the channel. It is the responsibility of the receiving digital audio interface to pull off the appropriate number of bits every time the LRCLK/frameclock fires and ignore the rest of it. For example in I2S mode, 2-channel, 32-bit, the DAI should pull off the first 32 bits following each LRCLK transition.
Thanks very much for adding this, sounds like this is basically how the part operates then. Although I feel the datasheet could have been more clear, apologies for that.
Thanks, Charles