SAI/I2S configuration, function, and connections?

[davenadler]

Background: MIMXRT1024CAG4B-based design, sending audio data via I2S to Bluetooth module (though could just be a pair of sound output DAC chips like pcm5101a), and possibly directly generating audio using MQS. The external Bluetooth module I'm using (as many other modules and the referenced DAC chip) expects these signals:

• BCLK, MCLK, DO, DI
• WS right-left channel stereo selector

Questions:

1) SAI module output does not include a WS signal. Where does WS come from on RT1024?

2) SAI1 has 4 TX and 4 RX lines. Can SAI1 be configured to use only one line?

3) Can MQS be fed with data from inside RT1024 or does it only work with an external I2S source?

4) What codec does MQS expect sound was encoded with?

Thanks!
Best Regards, Dave

[jingpan · Accepted solution]

Hi @davenadler ,

1. SAI1_TX_SYNC is the WS signal of I2S.

2. Yes.

3. Yes, MQS be fed with data from inside RT1024.

4. MQS (middle quality speaker) is used to convert the I2S audio data from SAI to PWM signals that can drive external speaker directly. It needn't codec. You can refer to this post for how to use MQS. https://community.nxp.com/t5/i-MX-Processors/RT1064-MQS-Driver-Circuitary/m-p/1348070

Regards,

Jing

[davenadler]

Got it, Thanks!