STM32F303VET6 – Debugging Issues with ST-LINK V2 in IAR EWARM 9.40.2

[kumarairia]

Hello Experts,

I am using an STM32F303VET6 MCU and developing in IAR Embedded Workbench for ARM version 9.40.2.
My project compiles correctly, and debugging works perfectly when I use the I-Jet debugger.

However, when I switch the debugger interface to ST-LINK V2, I experience several issues:

• Flash loading errors

• Debug session failing to start

• Random connection or SWD errors

• In general, the application fails to debug reliably

I have verified the following:

• The device appears in Device Manager as “STM32 ST-LINK”

• SWD wiring and connections

• Same board works fine with I-Jet, so hardware seems OK

Could you please advise on what additional configuration or driver settings I should check in order to make ST-LINK V2 work properly with IAR?
Any guidance would be greatly appreciated as this issue is urgent for my project.

Error log.

Tue Nov 18, 2025 17:43:52: IAR Embedded Workbench 9.40.2 (armPROC.dll)

Tue Nov 18, 2025 17:43:52: Loaded macro file: C:\Program Files\IAR Systems\Embedded Workbench 9.2\arm/config/debugger/ST/STM32F3xx.dmac

Tue Nov 18, 2025 17:43:52: Loaded macro file: C:\Program Files\IAR Systems\Embedded Workbench 9.2\arm/config/flashloader/ST/FlashSTM32F3xx.mac

Tue Nov 18, 2025 17:43:52: Connected to ST-LINK/V2 [SWD mode 1800 kHz] [Access port: 0] Firmware V2.J46.S7 (Probe no: 36FF70064D59303631062543)

Tue Nov 18, 2025 17:43:52: Hardware reset with strategy 0 was performed

Tue Nov 18, 2025 17:43:52: Initial reset was performed

Tue Nov 18, 2025 17:43:52: Loaded debugee: C:\Program Files\IAR Systems\Embedded Workbench 9.2\arm/config/flashloader/ST/FlashSTM32F3xxRAM64K.out

Tue Nov 18, 2025 17:43:52: Target reset

Tue Nov 18, 2025 17:43:56: Unloaded macro file: C:\Program Files\IAR Systems\Embedded Workbench 9.2\arm/config/flashloader/ST/FlashSTM32F3xx.mac

Tue Nov 18, 2025 17:43:56: Downloaded C:\Users\dkumar\Desktop\projects-\-KEEPSAFE\Final_641_onfly-vdc - Copy\641-24sep-2mint\EWARM\Release\Exe\641-24sep-2mint.out to flash memory.

Tue Nov 18, 2025 17:43:56: 82792 bytes downloaded into FLASH (19.24 Kbytes/sec)

Tue Nov 18, 2025 17:43:56: Loaded debugee: C:\Users\dkumar\Desktop\projects-\-KEEPSAFE\Final_641_onfly-vdc - Copy\641-24sep-2mint\EWARM\Release\Exe\641-24sep-2mint.out

Tue Nov 18, 2025 17:43:56: Write failed (CPU data abort) at Memory address 0x2000'0300

Tue Nov 18, 2025 17:43:56: Write failed (CPU data abort) at Memory address 0x2000'0300

Tue Nov 18, 2025 17:43:56: Write failed (CPU data abort) at Memory address 0xe000'1028

Tue Nov 18, 2025 17:43:56: Hardware reset with strategy 0 was performed

Tue Nov 18, 2025 17:43:56: Download completed.

Tue Nov 18, 2025 17:43:56: Hardware reset with strategy 3 was performed

Tue Nov 18, 2025 17:43:56: Target reset

Tue Nov 18, 2025 17:43:56: There were 3 warnings during the initialization of the debugging session.