BLE NUS central + USB (usb not enabled on power detection)

RE: BLE NUS central + USB (usb not enabled on power detection)

jeremysf — Fri, 24 Aug 2018 20:06:03 GMT

Any progress on this? I am having a similar problem which I documented here:

https://devzone.nordicsemi.com/f/nordic-q-a/37812/usb-not-enumerating-without-jlinkexe-running

I know my application is running because my custom hardware has an OLED screen which works, and my BLE functionality is working.

My device does not enumerate over USB unless I have JLinkExe connected with J-Link Pro over SWD. If I simply run JLinkExe and type "connect" to the running application, the USB immediately enumerates. I do not have to physically disconnect the JLink Pro from SWD to see the lack of enumeration (or the subsequent enumeration when using JLinkExe and"connect").

No amount of connecting/disconnecting a USB cable works with JLinkExe "disconnected" but once JLinkExe is running, I can connect/disconnect a USB cable repeatedly and get enumeration reliably.

RE: BLE NUS central + USB (usb not enabled on power detection)

Julian — Fri, 17 Aug 2018 01:24:34 GMT

Hi,

I did face that issue described in the link as I was previously using SES v3.40. Now I have downgraded to SES 3.34b, and no longer facing compile problems due to the _putchar() function.

However the issue still persists, and only happens when I include USB functionalities in the code. I am also running an NFC launch app function, and what's weird is that the NFC works on power up(without having to run in debug), which tells me that the code is running, but the USB fails to enumerate. It only enumerates if I force to run in debug, which might or might not be related to the issue in the link.

I will try out the workaround in the link which is intended for SES v3.40, and let you know of my result.

Thanks for your support!

RE: BLE NUS central + USB (usb not enabled on power detection)

Håkon Alseth — Thu, 16 Aug 2018 06:26:08 GMT

Sounds like you're seeing the same issue as this thread: https://devzone.nordicsemi.com/f/nordic-q-a/37477/unable-to-run-uart-ble-app-example-without-debugger

Could you try the workarounds posted there?

RE: BLE NUS central + USB (usb not enabled on power detection)

Julian — Thu, 16 Aug 2018 02:09:56 GMT

Hi Håkon, I may have spoken too soon.

Upon further testing, it seems that the USB only enumerates when it is running in debug mode (I'm using SES).

It doesn't enumerate if I run it normally, or after power cycle from a debug session.

RE: BLE NUS central + USB (usb not enabled on power detection)

Julian — Thu, 09 Aug 2018 06:48:56 GMT

Just applied the workaround posted. It now works reliably.

Thanks!

RE: BLE NUS central + USB (usb not enabled on power detection)

Håkon Alseth — Tue, 07 Aug 2018 06:55:44 GMT

Hi,

Unfortunately, we have a known issue with SDK v15, where the USBD erratas is not properly applied for the latest chip revision. Could you try the workaround posted here and see if this works?

https://devzone.nordicsemi.com/f/nordic-q-a/34605/usb-not-enumerating-after-reset/133051#133051

Kind regards,

Håkon