I am currently working with an STM32 MCU and facing an issue while trying to connect the board to my PC using an ST-LINK debugger. The board powers on normally and there does not appear to be any obvious hardware issue, but STM32CubeProgrammer is unable to detect the target device. The connection attempt either fails or reports that no target is found, so I am currently unable to program or debug the MCU.So far, I have checked the basic connections and setup:USB cable and ST-LINK connection Board power supply and voltage SWDIO and SWCLK connections STM32CubeProgrammer installation ST-LINK firmware and connection settingsI am not sure if the problem could be caused by the MCU configuration, SWD interface, boot mode, or some setting that may have been changed in the firmware. I would also like to know if there are any recommended STM32CubeProgrammer options or recovery procedures that should be tried when the target MCU is not detected.Has anyone experienced a similar issue with an STM32 MCU and ST-LINK? I would appreciate any suggestions for the best troubleshooting steps to identify whether this is related to the debugger, SWD connection, board configuration, or the MCU itself.

Associate

Question

STM32 MCU Connection Issue with ST-LINK

Forum|Forum|3 days ago
September 2, 2026
4 replies
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I am currently working with an STM32 MCU and facing an issue while trying to connect the board to my PC using an ST-LINK debugger. The board powers on normally and there does not appear to be any obvious hardware issue, but STM32CubeProgrammer is unable to detect the target device. The connection attempt either fails or reports that no target is found, so I am currently unable to program or debug the MCU.

So far, I have checked the basic connections and setup:

USB cable and ST-LINK connection
Board power supply and voltage
SWDIO and SWCLK connections
STM32CubeProgrammer installation
ST-LINK firmware and connection settings

I am not sure if the problem could be caused by the MCU configuration, SWD interface, boot mode, or some setting that may have been changed in the firmware. I would also like to know if there are any recommended STM32CubeProgrammer options or recovery procedures that should be tried when the target MCU is not detected.

Has anyone experienced a similar issue with an STM32 MCU and ST-LINK? I would appreciate any suggestions for the best troubleshooting steps to identify whether this is related to the debugger, SWD connection, board configuration, or the MCU itself.

D

db16122

Associate II

is there any error log can be shared？

T

teeeroad281Author

Associate

is there any error log can be shared？

Thanks for asking. I do have the error information from STM32CubeProgrammer, although I’m not sure which parts of the log are most useful for diagnosing an ST-LINK/SWD detection problem. The connection attempt basically ends with the target MCU not being detected, despite the board powering on and the SWD connections appearing correct.

I can share the relevant error log or the exact error message here. Would you recommend posting the complete CubeProgrammer log, or are there specific lines such as the ST-LINK connection result, SWD frequency, target voltage, or device detection message that would be most useful? Also, if the log indicates that ST-LINK itself is detected but the target is not, would that help narrow the problem down to the SWD connection or MCU configuration?

M

mfgkw

Associate II

Hi,

maybe it helps if you tell which ST-Link you use and how exactly it is connected to your MCU.