Cant get J-Link RTT Viewer to show log information

[Robin]

Hello again Nordic Pros,

I am trying to get some debug logging going using the 52DK running ble uart central under SDK 12.3 and RTT Viewer v6.4.

I have setup config.h as such:

and added this line to test getting a log with each RX event:

...
        case BLE_NUS_C_EVT_NUS_RX_EVT:
            NRF_LOG_DEBUG ("TEST!\r\n");
...

Yet there are no logs in any RTT Viewer Window when characters are sent via BLE.

What am I missing here?

Robin @ TL

I now have RTT-Viewer showing logs.  However, there are 2 problems:

1.) If I turn on timestamping, my board hangs,

2.) When logging is enabled, I cannot command the board via the terminal.

Any suggestions on how to remedy this issues is greatly appreciated!

Thanks 

Robin @ TL

[XavierYin]

If you use NRF_LOG_DEFERRED, log will be processed only when NRF_LOG_PROCESS() or NRF_LOG_FLUSH() is called. They're typically executed in the last loop part in main() as part of idle task. See SDK examples for this.

Otherwise, the simplest solution is turn NRF_LOG_DEFERRED off. This makes log processed in-place.

[Robin]

Hello Xavier,

I have tied both options for deferred logging,  Neither results in any messages in RTT Viewer.  Any other ideas would be greatly appreciated.  I am having the same problem with our custom board.  I get connected from RTT Viewer, but no messages.

Thank you

Robin @ TL

[XavierYin]

Have you tried any stock example provided by SDK that enables RTT by default?

[XavierYin]

Besides, is there any good reason to stick to SDK 12.3?

[Robin]

Yes I have tried to log via RTT with the uart central on the 52DK  under SDK 12.3.  Could not get log messages in that configuration either.

[Robin]

Yes, our board is based on the nrF51822.  12.3 is the latest SDK for that SOC.  And, there are problems using the latest SDK for the 52 and interfacing with our 51 product.  See my ticket on dropped characters.

At SDK 12.3 behaves well at both ends (peripheral and central), but I need a way of debugging while connected to a iphone.  RTT was the hopes but so far nothing seems to work.  A variety of problems, from RTT connect, but no log, to no connection to anything, depending on log setup on config.h.  Unstable to say the least.

Robin @ TL