USB Bulk IN Becomes Busy

[Laurence]

Hi,

I'm trying to use a Bulk IN endpoint (EPIN3)  and am running into an issue.

I call the nrf_drv_usbd_ep_is_busy() function to test whether it is safe to proceed with a transfer.

Whenever it reports not busy I proceed and everything seems OK.

When it reports busy, I wait to do the transfer later (with an application scheduled timer).

However, once it is busy it always stays that way (m_ep_dma_waiting is never cleared).

Are there known issues with the USB driver?

The documentation still refers to the USB driver as experimental.

I'm using the PDK for the NRF52840 (PCA10056 V0.9.2) with the nRF5 SDK version 14.2

Thanks,

Larry

[Håkon Alseth]

Hi,

It is very likely that you are experiencing the side-effects of erratum #104.

As shown in this list, there are quite a few erratas on the USBD for engineering A of the nRF52840.

I'd recommend to get a newer revision of the nRF52840 silicon to avoid the erratum #104.

Best regards,

Håkon

[Laurence]

How can I get a new revision?  Is this available now in a development kit?

[Håkon Alseth]

You can contact your regional sales manager to get more information on how to obtain the newest revision. If you do not already have the details of your RSM, send me a PM with your location and I can provide you with this.

Cheers,

Håkon

[Laurence]

Hi Hakon,

I'm not clear on the acronyms.  What do you mean by PM and RSM?

Thanks,

Larry

[Håkon Alseth]

Hi Larry,

RSM = regional sales manager, and PM=personal message.

Cheers,

Håkon

[Laurence]

Hi,

I have a new PDK.  PCA10056 Version 0.11.0.

Unfortunately USB doesn't seem to run at all.

It can't even enable USB.

In the debugger I can trace it to nrf_usbd_eventcause_clear(), where it seems to hang.

Called from nrf_drv_usbd_enable()

Any ideas?

Do I need a specific version of firmware to be loaded?

Thanks,

Larry