Kinetis Microcontrollers中的主题 MK22FN512 USB Composite device Audio + CDC, microphone don't work in audio device...

MK22FN512 USB Composite device Audio + CDC, microphone don't work in audio device...

evgeniyivanov — Mon, 28 Jan 2019 13:45:52 GMT

I am using SDK 2.5.0. Based on the example, I created a USB stack for a composite device AUDIO(speaker + microphone) + CDC(Vcom). For the basis, I took the example of usb_device_composite_hid_audio_unified_lite and replaced it HID on CDC. At first worked only CDC Virtual COM. I added IAD descriptor for Audio class. After that, the speaker began to work, but the microphone did not... Audio in conjunction with HID or MSC works fully.

What could be the reason?

Re: MK22FN512 USB Composite device Audio + CDC, microphone don't work in audio device...

jingpan — Fri, 01 Feb 2019 05:54:29 GMT

Hi Andre,

I think you need to check descriptor (g_UsbDeviceConfigurationDescriptor). HID use 1 endpoint. But USB-CDC vcom use 3 endpoint. Their type are also different. You have to check new descriptor length, endpoint, and many things. If everything is correct, the computer should recognize a speaker device attached.

Regards,

Jing