It is pretty straight-forward to use J-Link RTT Viewer on Windows (as described in the Debugging with Real Time Terminal tutorial). Is there a similar viewer to use with GNU/Linux?
I assume that you have already installed the latest Software and documentation pack from SEGGER.
To use the RTT Viewer equivalent on GNU/Linux, you must first set up the connection using JLinkExe. Provided that your DK or dongle is connected, starting JLinkExe from a terminal should look something like this:
you@yourcomputer:~$ JLinkExe SEGGER J-Link Commander V5.10u (Compiled Mar 17 2016 19:06:22) DLL version V5.10u, compiled Mar 17 2016 19:06:19 Connecting to J-Link via USB...O.K. Firmware: J-Link OB-SAM3U128-V2-NordicSemi compiled Mar 15 2016 18:03:17 Hardware version: V1.00 VTref = 3.300V Type "connect" to establish a target connection, '?' for help J-Link>
JLinkExe may decide to update the firmware on the Segger programmer IC, which will give additional information between "Connecting to J-Link via USB..." and "O.K."
The final line is a prompt. The "connect" command will present some choices along with default values and options. Defaults are mostly fine, but use "SWD" for target interface.
If a connection is established the final lines of output should state "Cortex-M0 identified" (for nRF51) or "Cortex-M4 identified" (for nRF52), followed by the "J-Link>" prompt:
(...) Cortex-M4 identified. J-Link>
Now, from another terminal, start JLinkRTTClient. This program should connect automatically:
you@yourcomputer:~$ JLinkRTTClient ###RTT Client: ************************************************************ ###RTT Client: * SEGGER MICROCONTROLLER GmbH & Co KG * ###RTT Client: * Solutions for real time microcontroller applications * ###RTT Client: ************************************************************ ###RTT Client: * * ###RTT Client: * (c) 2012 - 2014 SEGGER Microcontroller GmbH & Co KG * ###RTT Client: * * ###RTT Client: * www.segger.com Support: support@segger.com * ###RTT Client: * * ###RTT Client: ************************************************************ ###RTT Client: * * ###RTT Client: * SEGGER J-Link RTT Client Compiled May 27 2016 17:03:51 * ###RTT Client: * * ###RTT Client: ************************************************************ ###RTT Client: ----------------------------------------------- ###RTT Client: Connecting to J-Link RTT Server via localhost:19021 Connected. SEGGER J-Link V5.12g - Real time terminal output J-Link OB-SAM3U128-V2-NordicSemi compiled Mar 15 2016 18:03:17 V1.0, SN=682852586 Process: JLinkExe
You will now receive RTT output.
If you happen to like telnet you can use it instead of JLinkRTTClient:
you@yourcomputer:~$ telnet localhost 19021 Trying 127.0.0.1... Connected to localhost. Escape character is '^]'. SEGGER J-Link V5.12g - Real time terminal output J-Link OB-SAM3U128-V2-NordicSemi compiled Mar 15 2016 18:03:17 V1.0, SN=682852586 Process: JLinkExe
Works like a charm