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Debug issue



I have an issue debug issue in my custom board. The debug session works for a while and then stop to working and suddenly after many tries it works again.

When the debug session doesn't work, I get:

STMicroelectronics ST-LINK GDB server. Version 5.9.1

Copyright (c) 2021, STMicroelectronics. All rights reserved.

Starting server with the following options:

    Persistent Mode      : Disabled

    LogFile Name        : C:\Users\***\Debug\st-link_gdbserver_log.txt

    Logging Level       : 31

    Listen Port Number     : 61234

    Status Refresh Delay    : 15s

    Verbose Mode        : Enabled

    SWD Debug         : Enabled

COM frequency = 4000 kHz

Target connection mode: Attach

Reading ROM table for AP 0 @0xe00fffd0

Hardware watchpoint supported by the target 

ST-LINK Firmware version : V2J38M27

Device ID: 0x418

PC: 0x78f9e0

ST-LINK device status: RUN_MODE

ST-LINK detects target voltage = 3.26 V

ST-LINK device status: RUN_MODE

ST-LINK device initialization OK

Waiting for debugger connection...

Waiting for connection on port 61234...

Waiting for connection on port 61235...

Accepted connection on port 61234...

Debugger connected

Try halt...

ST-LINK device status: HALT_MODE

Enter STM32_HardwareReset() function 

STM32_HardwareReset(), failure reset target.

ST-LINK device status: RESET_MODE

 ------ Switching to STM32CubeProgrammer ----- 


            STM32CubeProgrammer v2.8.0          


Log output file:  C:\Users\***\AppData\Local\Temp\STM32CubeProgrammer_a14944.log

ST-LINK SN : 0668FF343537424257252146


Board    : NUCLEO-F302R8

Voltage   : 3.25V


Encountered Error when opening C:\ST\STM32CubeIDE_1.4.0\STM32CubeIDE\plugins\\tools\bin\STM32_Programmer_CLI.exe

 ------ Switching context ----- 

Error in STM32CubeProgrammer

Debugger connection lost.

Shutting down...

Stopping port 61235

Received stop for port 61235, not accepting new connections.

I use ST-LINK device and pins SWCLK, SWDIO and NRST are connected to the custom board MCU STM32F105VC. (of course 3.3v and GND).

The debug configuration is attached.

Thank you.

Chief II

Two possible mistakes , your code enter STOP or lower mode and you dont setup session to this.

Or you dont setup sonnecion under reset ...

Thank you for your reply,

The debug sometimes (when it works) ends in Error_Hanlder function.

void Error_Handler(void)


 /* USER CODE BEGIN Error_Handler_Debug */

 /* User can add his own implementation to report the HAL error return state */


 while (1)



 /* USER CODE END Error_Handler_Debug */


Perhaps migrate to the form of this that identifies the file and line it is called from, or pulls the return address so you can pin it down via symbols and .MAP or .ELF file.​

P​erhaps don't disable interrupts here, and double check NRST is properly connected.

C​heck clock startup code for failure cases.

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Up vote any posts that you find helpful, it shows what's working..

On the custom board, I am using two external 8MHz and 32KHz crystal oscillators. I have just disable the HSE from RCC configuration and it seems that the code doesn't run into the Error_Handler.

If the clock configuration is correct, then I have to check for the hardware.

If the HSE doesn't start it will trap. Should be a couple of points you can identify quickly with breakpoints in SystemClock_Config()

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Up vote any posts that you find helpful, it shows what's working..
Chief II

When your hardware fail, then ofcourse debuger crash too. For hw debug use scope ...

Thank you,

I will check for the hardware if something is wrong.

But would you please tell me, the reason I can't change the LSI to LSE in clock configuration (as I mentioned, I use two external crystal 8MHz/32KHz, HSE and LSE). A picture is attached.


I can verify that the 8MHz crystal is working on board when debug session is ok.

But I am still facing issue with debug.

RTC have to be enabled.