I2S input connections confusion: BM23 and Teensy 3.6

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cdh

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I am designing a bluetooth soundbar + audio visualizer using Teensy. For BT and aux support, I intend to use the BM23 , which provides 16 bit, 44.1k audio via I2S. This is my basic block diagram:
BlockDiagram.PNG

The BM23 is replacing the audio shield, but I have not been able to reconcile its desired pinout (below - page 18 in datasheet linked above; BLCK, DACLRC, ADCDAT, DACDAT) with Teensy's (BCLK, MCLK, RX, LRCLK).

BM23_I2S_Mode.PNG

These are my questions:
  1. Am I definitely using the BM23 in slave mode? Why would I use it in Master mode?
  2. If in Master mode, should the RFS0 pin be TFS0 (ie is there a mistake in the datasheet fig. 2-8)?
  3. I think BCLK ~ BCLK and DACLRC ~ LRCLK, but how do ADCDAT and DACDAT correspond to MCLK and RX? Do they at all?
  4. Am I constrained to 16bit, 44.1k? Can I use 24bit or 48k?

Thanks for any help! All the different labels have been pretty confusing.
 
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[*] Am I definitely using the BM23 in slave mode? Why would I use it in Master mode?
The mode is controlled by configuration of the device, the proper connections to use follow from that. Master mode would be required if you're using a DAC that only supports slave mode.

[*] If in Master mode, should the RFS0 pin be TFS0 (ie is there a mistake in the datasheet fig. 2-8)?
I'd use Slave mode and have T3.6 be Master.

[*] I think BCLK ~ BCLK and DACLRC ~ LRCLK, but how do ADCDAT and DACDAT correspond to MCLK and RX? Do they at all?
It looks to me like there's a contradiction between the diagram you posted and the pin assignment table on Page 10 of the Datasheet:

BM23 I2S.JPG
Either DR0 or DT0 is the I2S data from the BM23 to the T3.6. That's the one you want to connect to I2S0_RXD0 (T3.6 Pin 13). My guess is that the block diagram is wrong and the Table 1-2 is correct. It looks like BM23 does not require MCLK.

[*] Am I constrained to 16bit, 44.1k? Can I use 24bit or 48k?
48KHz Sample Rate -- Yes, but BM23 must be master and T3.6 slave. This also alters the behavior of certain other Teensey Audio Library objects and makes some unusable.
24-Bit -- Yes, but not with the Teensey Audio Library. You'll need to implement everything yourself.
 
Looks like you're right. Too bad the I2S write-up in the BM23 datasheet is so poor and uses non-standard signal names.
 
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