Cannot establish RTT logger

[Terry]

Hi,

I am using Ubuntu 16.04 (64-bits) OS.

I installed JLink_Linux_V620b_x86_64.deb and was using nRF5x-Command-Line-Tools_9_6_0_Linux-x86_64.tar

I can capture the debug messages using UART.

I followed the instructions stated on devzone.nordicsemi.com/.../, but failed.

After executed JLinkExe and inputed some parameters, I could get

Connecting to target via SWD
Found SW-DP with ID 0x2BA01477
Found SW-DP with ID 0x2BA01477
Scanning AP map to find all available APs
AP[2]: Stopped AP scan as end of AP map has been reached
AP[0]: AHB-AP (IDR: 0x24770011)
AP[1]: JTAG-AP (IDR: 0x02880000)
Iterating through AP map to find AHB-AP to use
AP[0]: Core found
AP[0]: AHB-AP ROM base: 0xE00FF000
CPUID register: 0x410FC241. Implementer code: 0x41 (ARM)
Found Cortex-M4 r0p1, Little endian.
FPUnit: 6 code (BP) slots and 2 literal slots
CoreSight components:
ROMTbl[0] @ E00FF000
ROMTbl[0][0]: E000E000, CID: B105E00D, PID: 000BB00C SCS
ROMTbl[0][1]: E0001000, CID: B105E00D, PID: 003BB002 DWT
ROMTbl[0][2]: E0002000, CID: B105E00D, PID: 002BB003 FPB
ROMTbl[0][3]: E0000000, CID: B105E00D, PID: 003BB001 ITM
ROMTbl[0][4]: E0040000, CID: B105900D, PID: 000BB9A1 TPIU
ROMTbl[0][5]: E0041000, CID: B105900D, PID: 000BB925 ETM
Cortex-M4 identified.

However, after I executed JLinkRTTClient, I just got

###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 - 2016  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 Sep 22 2017 17:58:45 * 
###RTT Client: *                                                          * 
###RTT Client: ************************************************************ 

###RTT Client: -----------------------------------------------
###RTT Client: Connecting to J-Link RTT Server via localhost:19021 ...

Please help. Thanks.

Terry

[Bjørn Kvaale]

I talked to a colleague at Nordic, and he noticed that you did not receive the prompt "J-Link>" after the line "Cortex-M4 identified." If this is the case, it makes sense that you cannot connect via the JLinkRTTClient. Also, it could be that something on your network is blocking the RTT client. This is because the JLinkRTTClient connects to JLinkEXE via the network (through the loopback address). Hope that helps a bit!