EP 8 IN enabled check when writing a USB audio device (microphone)

RE: EP 8 IN enabled check when writing a USB audio device (microphone)

Or — Mon, 23 Sep 2019 13:59:24 GMT

Look at the reply I wrote for this question.

You can find source code that shows this behavior in this question (the full main.c was posted 6 days ago by me)

RE: EP 8 IN enabled check when writing a USB audio device (microphone)

Edvin — Mon, 23 Sep 2019 13:51:02 GMT

How do you decide that the EP is disabled? Is it because it returns NRF_ERROR_INVALID_STATE? if so, do you know what check inside app_usbd_ep_transfer() or what function call that returns this?

RE: EP 8 IN enabled check when writing a USB audio device (microphone)

Or — Mon, 23 Sep 2019 12:51:30 GMT

What can disable an endpoint ?

Why does it gets disabled in the middle of operation ?

Is there a driver event for an endpoint getting enabled/disabled ?

RE: EP 8 IN enabled check when writing a USB audio device (microphone)

Edvin — Mon, 23 Sep 2019 11:56:51 GMT

Hello,

If you look into:

app_usbd_audio_class_tx_start() -> app_usbd_ep_transfer()

This function will check the EP: nrf_drv_usbd_ep_enable_check(ep), and it will return NRF_ERROR_INVALID_STATE. So it basically checks what you want to know, but if you like, you can use nrf_drv_usbd_ep_enable_check(ep); before calling app_usbd_audio_class_tx_start().