RTT Stability

[Yatekii]

Hi

How stable is the RTT module and how trustworthy is it?

It is marked as unstable and I do not get any messages from the modules.

I use:

• #define NRF_LOG_BACKEND_RTT_ENABLED 1
• #define NRF_LOG_ENABLED 1
• #define NRF_SDH_BLE_LOG_ENABLED 1
• #define NRF_SDH_LOG_ENABLED 1
• #define NRF_SDH_SOC_LOG_ENABLED 1

Maybe I missed some define (A mate that uses RTT says I didn't but who knows). If so I am very happy to hear which ones I am missing :)

To make sure RTT really works as I didn't get any outputs in the console, I tested it using SEGGER_RTT_WriteString(0, "Hello World!\n"); at the start of my main(). Now I got a print, but only after I halted the CPU once (which is bad because when I continue after the halt, the SoftDevice will crash which burns the entire purpose of using RTT instead of the debugger).

Now I am using OpenOCD with the RTT patch and a ST-Link. So I am not entirely sure if itss their fault or if RTT is unstable from the nRF side too (:

Please don't just write "Use Segger stuff blabla" ... It's no help and no new information. I could use the overly expensive J-Link but I rather make it work with open source tools and the 2.50$ ST-Link.

Thanks for any information concerning the RTT module status :)

Best wishes

Noah

[Sigurd]

Hi,

What SDK version is this? You should use the NRF_LOG_INFO() macro for priting in the newest SDK versions. In e.g. SDK 14, we have this line in the main loop to process the log:

if (NRF_LOG_PROCESS() == false)
{
    power_manage();
}

Do you have this ? What SDK example is your code based on?

[Yatekii]

Hi Sigurd, thanks for the quick answer!

Sorry for not invluding the version ... I have ported everything to SDK v14.0.

Yes, my main loop contains those lines :) The SDK example my code is based on is the HRM/BAS.

Also I cannit print the SDK version as the RTT seems not to be working, remember? ;P

[Turbo J]

We don't see the RTT patch for OpenOCD that you use - but it is almost 100% likely the source of your problems. Note that some ST-Links can be upgraded with J-Link firmware.

[Yatekii]

Ok I will try and have a closer look at the patch then :)