Remove HID from evkmimxrt1170_dev_composite_hid_audio_unified_bm_cm7 example

[lexxvir]

Hi there,

I need USB Audio 2.0 device that's consists of speaker and recorder. I have found evkmimxrt1170_dev_composite_hid_audio_unified_bm_cm7 example in the SDK and it works fine.

Now I would like to remove HID part from this composite USB device to get regular USB Audio device.

But when I removed HID from the Device Descriptor and from the code USB Audio device doesn't work anymore.

The USB device is detected successfully by the OS (Ubuntu 22.04). I see the USB Audio device, it has right number of the channels (both speaker & recorder). But, when I try to record a sound no data is recorded. As I see the host doesn't polling device at all (but it does it for short time when device is connecting).

Attached default example with my changes.

[EdwinHz · Accepted solution]

Hi @lexxvir,

Removing USB functionality to the example code is not as simple as changing the device descriptor. This example code was designed to be used as HID. I believe you are probably better off merging the "dev_audio_speaker" and "dev_audio_generator" example codes together, rather than removing the HID part of the "dev_composite_hid_audio_unified_bm", more so if using the bare metal version.

BR,
Edwin.

[lexxvir]

Thank you for the answer!