KL26 SAI - when using RX in synchronous mode, what to do with SAI_RX_SYNC/SAI_RX_BCLK pins? NC, tie to TX clocks?

[jasonmatocha]

The Reference Manual for KL26 I2S port is unclear what to do with the clocks of the block that is in synchronous mode.

[Alice_Yang]

Helloo Jason,

- SAI_RX_SYNC is receive frame synchronization , connect to the SAI_TX_SYNC of other SAI interface .

SAI_RX_BCLK is the clock of receive bit , connect to the SAI_TX_BCLK of other SAI interface .

- About the configuration of SAI clock , please refer to : 5.7.10 I2S/SAI clocking of the KL26 reference manual.

configure the related registers .

And if you use the CW or KDS IDE, you can create one project with PE, then add the component "Init_I2S", configure the CLOCK:

Hope it helps

Have a great day,
Alice

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[jasonmatocha]

Hi Alice,

Thanks for your response.  My main question was if I want to master the SAI TX and slave the SAI RX to the SAI TX clocks, when I put SAI RX into Synchronous mode, do I have to physically route the SAI TX BCLK and FS to the SAI RX.  If not, I save 2 pins for other use.

I actually tried this out (had to make some mods to the SAI driver), and found that if SAI RX is in Synchronous mode, I do NOT have to physically drive SAI RX clocks.  That was good news.