AUD-EXP-42448 instructions

[expertsleepers]

I have the AUD-EXP-42448 and the MIMXRT1040-EVK. I was surprised not to find documentation anywhere explaining what steps need to be taken to get these two working together, and to convert an SDK example to work with the 42448 codec instead of the one on the board.

I've done everything I can think of (changed the driver in the SDK, changed to the correct LPI2C instance) and I'm not getting terribly far. Something is happening on the i2c pins but it's not right.

Any help would be very welcome.

[jingpan]

Hi @expertsleepers ,

Yes, currently there is only AN13291 which is about CS42448. You can refer to it's software. But it's base on RT1060. So you need to change pin configure.

Regards,

Jing

[expertsleepers]

Thanks. I did see that application note, but missed that there was any associated software. It's not very obvious that there's a link to it.

Anyway, in the meantime I figured it all out myself, and it's working.

My current problem is getting DMA working for input from the card. Is there an SDK example like "SAI EDMA Ping Pong Buffer Half Interrupt" that shows DMA input as well as output?

[jingpan]

Hi @expertsleepers ,

No, it seems all the sai edma examples are about playback. But I think it's not difficult to modify them to output data from sai. you can also refer to other peripherals demo, like lpspi. Because there edma configuration is almost same.

Regards,

Jing