RE: How to enable blocking log output with RTT? - SDK15

Andy — Fri, 04 May 2018 12:07:08 GMT

Disabling deferred logging indeed solves the problem :) This wasn't an issue previously in SDK 13 though.

RE: How to enable blocking log output with RTT? - SDK15

Einar Thorsrud — Fri, 04 May 2018 11:53:59 GMT

Hi Andy,

Are you using deferred logging?

Blocking at the RTT level seems to work. I have tested with the following simple code. I can see that there is no gap in the printed numbers even if I disconnect the RTT viewer for a period of time before reconnecting.

    while(true)
    {
        i++;
        NRF_LOG_INFO("%i", i);
        NRF_LOG_PROCESS();
    }

However, the higher lever nrf_log module does not support blocking per se. So if you use deferred logging in a more realistic way, calling NRF_LOG_* multiple times before calling NRF_LOG_PROCESS(), you could fill up the nrf_log buffer. This is not the same as the RTT buffer, and is defined by NRF_LOG_BUFSIZE in sdk_config.h. Not using deferred logging should solve the issue in this case (though I have not tested).

RE: How to enable blocking log output with RTT?

Andy — Thu, 03 May 2018 10:50:07 GMT

Any update on this? I still haven't figured out how to make the output blocking.