nRF52 RTT Log Not Showing All Messages

RE: nRF52 RTT Log Not Showing All Messages

Einar Thorsrud — Mon, 20 Aug 2018 06:06:58 GMT

I see.

It might be worth a shot to try deferred logging with a large NRF_LOG_BUFSIZE, then. As you don't get any log output with deferred logging I wonder if you handle printing of logs in your main loop, typically before going to sleep? You can refer to any of the example applications in the SDK that use deferred logging or the Logger module documentation for how to do it. Essentially you need to call NRF_LOG_PROCESS() repeatedly until it returns false (indicating that there are no more logs to process) before going to sleep.

RE: nRF52 RTT Log Not Showing All Messages

awneil — Fri, 17 Aug 2018 00:21:22 GMT

[quote userid="7377" url="~/f/nordic-q-a/37424/nrf52-rtt-log-not-showing-all-messages/144136"]I expect the problem is that your application produces logs faster than they are processed. Even if you don't use deferred logging, the RTT buffer will eventually fill up if you log too fast.[/quote]

I have found that it is very easy to log "too fast".

Or, in other words, the RTT logging is rather "low bandwidth".

So you really need to minimise the amount of debug you're sending.

I don't know if you can get any better performance over the UART ... ?

Make sure that you don't have this error in your NRF_LOG_PROCESS handling: https://devzone.nordicsemi.com/f/nordic-q-a/34666/nrf5-sdk-v15-0-0-bug-report-incorrect-use-of-nrf_log_process-in-ble_app_uart-peripheral-example-among-others

RE: nRF52 RTT Log Not Showing All Messages

Muhammet YILDIZ — Thu, 16 Aug 2018 15:02:58 GMT

Acctualy it is not. For small strings yes it is working well. But in my case it is not.

I am building json objects and it is little nested and have some nested arrays and objects.

I closed almost all the nrf_logs (committed) and almost only one is available. That takes a char pointer which is printing json string.

Still i cant get all the message i need to see.

I have see it preperly to detect json problems and see any memory lekages. When i finish my job, i am planing to delete json print and close de debug define.

So i realy need the log works preparly. Please can you help me with this?

When i enable defered option, there is no message on the segger rtt viewer.

RE: nRF52 RTT Log Not Showing All Messages

Einar Thorsrud — Tue, 14 Aug 2018 11:21:26 GMT

Hi,

I am glad to hear you got it working.

(By the way, it makes sense that increasing NRF_LOG_BUFSIZE does not work if that is all you changed. The lager buffer is only useful in case you use deferred logging, which you are not.)

RE: nRF52 RTT Log Not Showing All Messages

Muhammet YILDIZ — Tue, 14 Aug 2018 10:57:15 GMT

Even if i increse the NRF_LOG_BUFSIZE to 16384, nothing changes.

But when i increase SEGGER_RTT_CONFIG_BUFFER_SIZE_UP to 512, it solves my problem for now.

RE: nRF52 RTT Log Not Showing All Messages

Einar Thorsrud — Tue, 14 Aug 2018 10:53:15 GMT

Hi,

I expect the problem is that your application produces logs faster than they are processed. Even if you don't use deferred logging, the RTT buffer will eventually fill up if you log too fast.

There are a few possible ways to handle this:

Increase the RTT buffer size
Reduce the amount of logging

You could also consider using deferred logging with a very large NRF_LOG_BUFSIZE. Assuming your application only produces a large number of logs for a short time, then it would perhaps have time to process the logs later when things settle down.