J-link error but BLE program seems to continue, no error log

RE: J-link error but BLE program seems to continue, no error log

FK42 — Fri, 04 Aug 2023 11:40:35 GMT

Hi Hung,

I tested it with a second development kit, and it works perfectly now.

I wouldn't know what the exact issue is with the other board, but I'm happy that it works.

Thank you for your assistance.

Frederik

RE: J-link error but BLE program seems to continue, no error log

FK42 — Fri, 28 Jul 2023 11:05:09 GMT

I will receive a second board next week, I will send you an update then.

Thank you for your time and consideration.

RE: J-link error but BLE program seems to continue, no error log

Hung Bui — Fri, 28 Jul 2023 11:04:11 GMT

Hi Frederik,

I don't have a clear idea on what could be wrong here. If you can test on another DK then we can rule out the issue with hardware/the chip.

If you do see the issue on another board then it could be something with the firmware. But as you mentioned it's running fine so I am not sure what could be wrong here.

RE: J-link error but BLE program seems to continue, no error log

FK42 — Thu, 27 Jul 2023 13:27:48 GMT

I will try to get a hold of another development kit.

After running some more tests:

1. When it crashes, it seems the LED stays on and does not start blinking. This indicates the NRF52840 itself does not reset.

2. When I run the hrs example, I am able to open the memory window and find the memory address that is shown in the error:

When I try to do the same in my program, Segger immediately crashes.

Does this also point to the DK being faulty, or could this mean something else?

RE: J-link error but BLE program seems to continue, no error log

Hung Bui — Thu, 27 Jul 2023 12:27:36 GMT

I don't see a problem reading address 0x20004754. It's application memory address and should be available to the application.

I would strongly suggest to get hold of another DK and test again.

RE: J-link error but BLE program seems to continue, no error log

FK42 — Thu, 27 Jul 2023 11:47:19 GMT

Unfortunately I do not have another DK available at the moment. I do have a PCB I just received with an nRF52840 on it, but using that could introduce other uncertainties.

The error I mentioned above is when running my firmware, not the ble_app_hrs example, by the way. Apologies for the confusion.

I've been running the ble_app_hrs_pca10056_s140 for around 15 minutes now without issue. So it seems the issue is my firmware.

I am guessing one of my BLE functions is trying to read an invalid memory address, as running just the TWI functionality worked fine.

EDIT: following this guide from nordic, I made sure I had the right memory definitions. Now that I adjusted it, the same error still occurs but now at a different address:

Error reading from memory address 0x20004734

RE: J-link error but BLE program seems to continue, no error log

Hung Bui — Thu, 27 Jul 2023 11:22:12 GMT

I think there must be something wrong with the hardware on the DK. Either too long USB cable, or something wrong with the debugger.
Please try to test with another DK to see if you have the same error. Please also try with another USB cable, and connect to another USB port, preferably directly to the mainboard.

RE: J-link error but BLE program seems to continue, no error log

FK42 — Thu, 27 Jul 2023 10:59:12 GMT

Hi Hung,

Thank you for your fast response and your assistance.

Debugger: I assume SES uses the installed debugger on my desktop, which is V7.88. I am not actively using the software but only using SES.

I will apply your suggestion about having a LED blink when the device boots up.

I will see if I can find another DK to test with.

SES: I was using SES version V7.30. I installed V5.42a and now running some tests. It still gives an error, but this time its a bit more informative:

Running another test results in:

I received the "Error reading from memory address 0x20004754" countless times in quick succession before losing the target connection.

The last message in the debug terminal is once again BLE event: 0x57.

Please forgive my ignorance, but do you have an idea how I can best figure out the root cause of this memory error?

RE: J-link error but BLE program seems to continue, no error log

Hung Bui — Thu, 27 Jul 2023 09:06:18 GMT

Hi Frederik,

Could you try to test debugging with one of our example, ble_app_hrs for example ?
I suspect that it's an issue with the debugger and has nothing to do with the application or the communication between the DK and the phone.
You can verify that the device was not reset by having a LED blink when the device booting up for example.

Do you have other DK to test ?

Which Jlink version you are using ? And which SES version ? Please try to use the SES version (5.42a) mentioned in the release note of the SDK https://infocenter.nordicsemi.com/topic/sdk_nrf5_v17.1.0/index.html?cp=9_1_0