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Issue flashing onto Nucleo L496ZGP board using detached ST-Link


I am trying to simply flash onto my nucleo board using the default configurations that the STM32CubeIDE generates for me. I have detached the ST-Link and connected it externally to the board as shown below: 


Table 1 of the connections from the ST-Link to the board

CN5 Pin 1 (VDD)CN8 Pin 4 (3.3v)
CN5 Pin 2 (SWCLK)CN11 Pin 8 (PA_14)
CN5 Pin 3 (GND)CN8 Pin 6 (GND)
CN5 Pin 4 (SWDIO)CN11 Pin 7 (PA_13)
CN5 Pin 5 (NRST)CN8 Pin 3 (NRST) 
CN5 Pin 6 (SWO)CN7 Pin 8 (PB_3)
JP1 Pin 1 (PWT_EXT)CN11 Pin 6 (3.3v) 
JP1 Pin 2 (GND)CN12 Pin 5 (GND)

Note: on the ST-Link, the jumpers on CN4 were taken off. And on the board, the jumpers for JP4 were taken off. The configuration decisions were based on the documentations


When running the STMCubeProgrammer, the following configurations are shown: 


Note: I am not sure why, but the target voltage is extremely low but the stm32 on the board is receiving the 3.3v needed to operate. 

In the IDE, I selected the correct board (STM32 L496ZG-P), and enabled UART4 to use just for an example. When the code is generated, below are the run configurations I am using: 


Overall, the memory segments from 0-19 (all 20) gets erased, but I am having issues trying to flash onto the memory segments as shown below: 


I have done the following in an attempt to fix this: 

  • Download a new driver
  • use older versions of the cube ide
  • configured different UART ports
  • Tried using an External Loader

I don't even know what the problem is honestly. I've gotten about 4 different errors including an error in erasing memory or even expected byte issues. But the most common one is failed to download segment[0]. Any help is appreciated.

Thank you


Did you manage to figure out what the error was? I'm having the exact same problem trying to accomplish the same task