How to use RTT Viewer (or similar) on GNU/Linux?

[tesc]

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?

[tesc]

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: [email protected]       *
###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

You will now receive RTT output.

[rusger]

Works like a charm

[wko]

Note that to get the tab completion behavior to work correctly via the telnet client, we need to enter 'character at a time' mode.  To do this, after connecting, enter "^]", then "mode character":

rtt_cli:~$ ^]
telnet> mode character

rtt_cli:~$ 
  app_size        balloc          clear           cli
  counter         dynamic         error           flashlog
  history         log             log_msg         nordic
  print           python          queue           reset
  resize          stack_overflow

[gnf]

Nice! "mode character" enables tab completion. But on my system it disables the backspace functionality (I cannot delete already written characters). Strangely enough, Ctrl+Backspace does the trick. Is it possible to enable normal backspace behaviour?