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NUCLEO-WBA55CG JTAG/SWD not able to connect via JLink

sfarnswo
Associate

I am attempting to connect to the STM32WBA55CG using a JLink Compact Plus following the following instructions from SEGGER: https://wiki.segger.com/ST_NUCLEO-WBA55CG.

This connection fails as the DAP is not responding. The output from JLink is attached below:

 

 

SEGGER J-Link Commander V7.96g (Compiled May  8 2024 15:03:51)
DLL version V7.96g, compiled May  8 2024 15:03:24

Connecting to J-Link via USB...O.K.
Firmware: J-Link V12 compiled Apr 23 2024 10:41:21
Hardware version: V12.00
J-Link uptime (since boot): 0d 00h 39m 37s
S/N: 852002069
License(s): RDI, FlashBP, FlashDL, JFlash, GDB
USB speed mode: High speed (480 MBit/s)
VTref=3.303V


Type "connect" to establish a target connection, '?' for help
J-Link>connect
Please specify device / core. <Default>: STM32WBA55CG
Type '?' for selection dialog
Device>
Please specify target interface:
  J) JTAG (Default)
  S) SWD
  T) cJTAG
TIF>S
Specify target interface speed [kHz]. <Default>: 4000 kHz
Speed>
Device "STM32WBA55CG" selected.


Connecting to target via SWD
InitTarget() start
SWD selected. Executing JTAG -> SWD switching sequence.
Error: Failed to initialized DAP.
Can not attach to CPU. Trying connect under reset.
SWD selected. Executing JTAG -> SWD switching sequence.
Error: Failed to initialized DAP.
Connecting to CPU via connect under reset failed.
InitTarget() end - Took 303ms
Connect failed. Resetting via Reset pin and trying again.
InitTarget() start
SWD selected. Executing JTAG -> SWD switching sequence.
Error: Failed to initialized DAP.
Can not attach to CPU. Trying connect under reset.
SWD selected. Executing JTAG -> SWD switching sequence.
Error: Failed to initialized DAP.
Connecting to CPU via connect under reset failed.
InitTarget() end - Took 305ms
Error occurred: Could not connect to the target device.
For troubleshooting steps visit: https://wiki.segger.com/J-Link_Troubleshooting

 

 

I am able to connect to the device using the STM32CubeProgrammer with the embedded STLINK, but I prefer to use a JLink for development to keep all our debug tools identical between products.


Please advise.

1 ACCEPTED SOLUTION

Accepted Solutions
sfarnswo
Associate

After some investigation of a SWD trace from the board, it appears as though the on-board STLINK was holding the SWCLK signal high and not allowing the attached JLink probe to toggle the signal. Removing R34 from the board has resolved the issue.

View solution in original post

1 REPLY 1
sfarnswo
Associate

After some investigation of a SWD trace from the board, it appears as though the on-board STLINK was holding the SWCLK signal high and not allowing the attached JLink probe to toggle the signal. Removing R34 from the board has resolved the issue.