Segger RTT - How to increase maximun line count?

[muhkuhns]

I want to use Seggers RTT for data logging.. but after 199lines the Viewer starts to overwrite the old lines.. so that only the most recent 199 lines are displayed..

Are there by the way any other tools I can use instead of the standard one?

[Lück]

Hi muhkuhns. I have the same problem that I want to use RTT for data logging as UART printf() is too slow. In addition I need to log data from three devices connected to the PC at the same time. Therefore I would be verry interessted in your solution for that issue. Did you find a solution so far? Or does someone else know how to log data with RTT?

[muhkuhns]

see my addes answer. btw: You should have posted this as the comment it is, and not as an answer.

[Lück]

All right, I found a possibility:

• download the Segger Software and Documentation pack
• extract and install it (do not replace existing DLLs as it may conflict with an existing tool chain)
• in the install folder (e.g. "C:\Program Files (x86)\SEGGER\JLink_V502f") find the JLinkRTTLogger.exe application and start it
• enter the device name which is the Segger serial number of the device (maybe also any other name works?)
• follow the instructions and enter the required parameters
• select the device from the popup but do not update the device firmware (if asked)
• in device selection prompt (if shown) press "Yes" and select your target device (in my case nRF51822_xxAA)

Now the logger started to log...

[Lück]

@ muhkuhns: I cannot see any other answer or comment in this thread giving a solution. The solution I described works but the performance is even worse than with UART printf. I have up to four values to be logged every 1ms. With UART printf I miss approx. 55% and with RTT approx. 70%. Do you have experienced any performance issues like this?