nRF52840 USB example crash

RE: nRF52840 USB example crash

ilia — Tue, 29 Aug 2017 17:45:29 GMT

Hi @pbirkner, basically using the another board solved the problem. With new board I am able to flash and run precompiled .hex from the SDK (now I use 14.0 version). But I have not managed to make VisualGDB projects working on any of my boards yet.

RE: nRF52840 USB example crash

pbirkner — Tue, 29 Aug 2017 17:26:39 GMT

Has there been any resolution of this issue? I am having the EXACT same problem.

RE: nRF52840 USB example crash

Hung Bui — Fri, 04 Aug 2017 09:07:31 GMT

Hi Ilia,

No I don't think you can damage the board with the hex file. Today I got some time to test the board and when scoping on the 2 Data line, I found that on one of the line it's completely flat when I plug the USB in, seems that it's unconnected to either the chip or the USB port. I would suggest you to hook a logic analyzer on the TP13 and TP14 and check if there is any signal on it.

RE: nRF52840 USB example crash

ilia — Thu, 03 Aug 2017 15:54:15 GMT

The HID Composite example is working. Not absolutely stable, but it works. Other examples I have not tried yet. Thank you. Is there a possibility to damage my board when flashing SDK example which was built with VisualGDB?

RE: nRF52840 USB example crash

Hung Bui — Thu, 03 Aug 2017 15:30:50 GMT

Hi Ilia,

It 's strange. Could you also try with the usbd_hid_composite example ? and the cdc_acm or mcs example ? (for the cdc example you may need to follow this guide to install the driver: devzone.nordicsemi.com/.../)

We released SDK v14 today, it might also help.

RE: nRF52840 USB example crash

ilia — Thu, 03 Aug 2017 15:20:17 GMT

Hi @hungbui,

I've got another nRF52840 PDK with the same revision as my previous board, and USB HID Generic sample started to work. The device is correctly recognized as input device now. The only issue left - the device does not behave as stated in the SDK documentation. The LED2 which should show the USB library status is always OFF which means "USB library stopped". And my PC does not react to button click events from the board.

RE: nRF52840 USB example crash

Hung Bui — Wed, 02 Aug 2017 13:12:12 GMT

No, you don't need to configure any jumper or connectors (SW6 to Default, SW9 to VDD). USB Generic should work out of the box. I haven't got chance to debug my board yet.

Is it possible for you to replace the board ?

RE: nRF52840 USB example crash

ilia — Wed, 02 Aug 2017 11:14:40 GMT

Hi @hungbui,

Ok, programming with nRFGo gave the same result. What about jumpers and connectors? Do I need to connect some pins? Also you have said, that you have one PDK board with not working USB examples. What revision does this board have? And what revisions does the working boards have? My board's revision is 0.9.2 2017.25.

RE: nRF52840 USB example crash

Hung Bui — Wed, 02 Aug 2017 07:56:26 GMT

No, the USB example doesn't require softdevice. It's fine to do drag and drop. But we usually suggest to use nRFGo Studio or nrfjprog tool to do flash programming, instead of drag and drop to the USB drive.

RE: nRF52840 USB example crash

ilia — Wed, 02 Aug 2017 06:40:30 GMT

One more question, just for clarification for flashing process. Do I need to flash specific soft device, make some other configuration changes to the board to run precompiled .hex? And to flash this .hex, I just copy it to the board, which recognized as USB drive.

RE: nRF52840 USB example crash

ilia — Tue, 01 Aug 2017 12:25:55 GMT

Hi @hungbui,

Yeah, you are right, I have already compiled with gcc and flashed the resulted .hex to the device and got the same situation with not recognized USB device.

RE: nRF52840 USB example crash

Hung Bui — Tue, 01 Aug 2017 12:09:49 GMT

I'm sorry that it's a little bit busy here to test the VidualGDB project. But if you have issue with the precompiled hex I don't think it's about your project setting of start up file. HID device should work out of the box. I would suggest to acquire another nRF52840 PDK for testing and replace your current board. If you want to compile and test an example, I would suggest to also try with gcc. But I don't think it would make any different compare to the pre-compiled hex.

RE: nRF52840 USB example crash

ilia — Mon, 31 Jul 2017 10:29:25 GMT

Hi @hungbui,

I have already used another PC, and I have only one DK to test. Here is sample project from the SDK created for VisualGDB

RE: nRF52840 USB example crash

Hung Bui — Mon, 31 Jul 2017 10:11:06 GMT

Could you send the project you used ? If you have problem with the pre-compiled hex file, I would suspect that it's a hardware issue. Could you try on other PC ? Also if you have another DK please try that also.

RE: nRF52840 USB example crash

ilia — Fri, 28 Jul 2017 10:53:55 GMT

Hi @hungbui,

Situation #1:

I use HID_Generic example code from the SDK with VisualGDB on Windows PC. I flash and run the code with debugging. Everything is working - the board is just waiting for USB connection. Then I connect the second USB cable and project crashes with exception SIGTRAP in the exact same location as in the referenced thread. And I don't see how to change startup file because in project references there is ".c" startup file and not ".s".

Situation #2:

Flash precompiled .hex -> the PC will not recognize the device.

RE: nRF52840 USB example crash

Hung Bui — Fri, 28 Jul 2017 10:12:21 GMT

Sorry I'm not very familiar with the USB stuff. But what exactly "reent.c" you talked about ? In the case about start up file you pointed to, it's pretty straight forward, he used the wrong start up file , so the interrupt vector was configured wrongly. It's the arm_startup_nrf52840.s start up file.

Could you described exactly what happens ? If you don't plug the USB in, do you have the issue ? If you plug USB in what exactly happens ? Do you have assertion, hardfault or something ?

On my board, the code execute with no problem, the only problem is that the PC couldn't recognize it. I assume you are testing with a Windows PC ?

RE: nRF52840 USB example crash

ilia — Thu, 27 Jul 2017 12:37:31 GMT

Hi @hungbui,

could SIGTRAP exception while debugging be a hardware problem too? What about this thread, I referenced in my question. I have already checked different cables as well as different ports and PCs.

RE: nRF52840 USB example crash

Hung Bui — Thu, 27 Jul 2017 11:37:11 GMT

Hi Ilia,

I suspect hardware issue. Have you tried to use shorter USB cable ? I also have a PDK board that couldn't run any USB examples (USB device not recognized) when other boards worked just fine ( the precompiled hex should work). When we have some more time, I will try to check why that happened.

For now, I would suggest to test on other board.