This article describes some common issues and gives possible causes and remedies.

1 STM32CubeMonitor cannot connect to the board

Possible cause:

  • The firmware running on the target is forcing a Low power mode. Communication with ST-LINK is disabled when the board is in Low power mode.
  • The target is secured or debug-disabled. STM32CubeMonitor is not able to connect in this case.

2 STM32CubeMonitor cannot connect to the board in TCP mode

Possible cause and remedy:

  • The STLLinkServer driver is not present. Install STLink server.
  • Another application is connected without Shared mode on the ST-LINK. Set the other applications to share the ST-Link .

3 Get application server port already in use error

Possible cause and remedy:

  • if it concerns port 1880 already in use, even if netstat doesn't show this port as being used, the error may be due to 'Hyper-V'. By disabling Hyper-V, it should work

4 STM32CubeMonitor doesn't show variables in .elf file on Ubuntu 19.10

Possible cause and remedy:

  • It seems to be an issue with the gdb parser used to decode the elf file. Gdb need the library libncurses5, and it it not available on ubuntu19.10. You can install the library with the command : "apt install libncurses5", it should solve the problem.

5 STM32CubeMonitor plots variables but their values seem to be 0

Possible cause and remedy:

  • When the processor is in WFI, the tool is not able anymore to access the memory : when the tool reads data, the probe returns 0 and not the real value. So it is not possible to get the data when MCU uses WFI instruction, you need to remove __WFI(); instruction.