Hi, @DeeY
For I2C communication, please refer to our SDK:
SDK_2_2_9_QN908XCDK\docs\MCUXpresso SDK API Reference Manual_QN908x\
There are some html files you can open and refer to.
Compile our SDK and download it form this link:
https://mcuxpresso.nxp.com/en/welcome
Only input QN9080 after click "Select Development Board", then compile and download it.
And also, after install the SDK, you can import below I2C examples to check source code.
Christine_Li_0-1704363857268.png