RTT Viewer / nrfjprog Issue

[jsample]

If I have the J-Link RTT Viewer open and connected to my PCA10056 (viewing RTT output from an external board connected to P19) and then reprogram the board using nrfjprog this will result in both nrfjprog and RTT Viewer locking up until I unplug and plug back in the PCA10056.  When this happens RTT Viewer prints the following error: "Communication timed out: Requested 12 bytes, received 0 bytes!"  Sometimes this won't happen and it will program just fine and RTT will print out after the boards resets, but the majority of the time it does.  This never used to happen though and I'm not sure what changed to cause it.  If I disconnect the RTT Viewer, program, then reconnect RTT I don't have any problems, but it's annoying to have to do this everytime I want to program the board.

Has anyone one else had this problem?

[Jeff4BLE]

Hi John,

It is not possible to run nrfjprog while connected to the RTT viewer. The tools use the same virtual com port and only one can be connected at a time.

In my experience with Windows systems, this has always been the case. I would not think that this would be OS dependent issue. But I wanted to add this just in case.

Best regards,

Jeff

[jsample]

Hi Jeff,

From my experience on Windows when things are working I can have RTT Viewer open and logging, flash a new build via nrfjprog and then RTT Viewer will pick up the RTT output after the chip resets without issue.

When things aren't working I'll have to disconnect RTT, then flash via nrfjprog, then reconnect.

John

[jsample]

Tried installing the latest on my coworkers Win10 computer as well and see the same behavior as my system.

[Jeff4BLE]

Hi John,

I just learned of the 64 bit version yesterday. I sent a note to the web team that this needs to be easier to find.

BTW- I just switched from using the PCA10040 to PCA10056. No changes in behavior.

Cheers,

Jeff

[Jeff4BLE]

What version of the PCA10056 board are you using?

[jsample]

I'm using a PCA10056 V1.0.0 my coworker is using a PCA10040 V1.0.0.

[Jeff4BLE]

I have used PCA10056 V1.0.0 and PCA10040 V1.0.1.

[jsample]

Hi Jeff,

By default the script file box was populated with the text "undefined", but I've found if I clear that then I don't get the popup I mentioned.  It was "undefined" on the older version as well, but didn't cause the popup so it must just be a change Segger made.  This doesn't seem to change the behavior in any way though.

The device I am programming is a custom nRF52840 board connected to the PCA10056 through the P19 Debug out connector.  I just tried disconnecting my board and programming the PCA10056 itself and see the same issues though.  

One more thing I've noticed is that when the issue occurs and nrfjprog and RTT Viewer both lock up, if I wait awhile instead of resetting the dev board Windows will eventually give me a "USB Device not recognized popup".  If I go into Device Manger the PCA10056 no longer shows up under ports and is instead listed as an "Unknown USB Device (Device Descriptor Request Failed".

So maybe the problem is with the PCA10056?

John