STM32 Not Detected via ST-Link V2 – Voltage Detected but No Connection

[RShashank]

Hi everyone,

I'm having trouble flashing my STM32 microcontroller using an ST-Link V2. STM32CubeProgrammer detects the target voltage, but it fails to connect to the MCU. Here's a summary of my setup and what I've tried:

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Setup:

• Microcontroller: STM32H723ZGT6

• ST-Link Version: ST-Link V2

• Flashing Tool: STM32CubeProgrammer (latest version)

• Connection Interface: SWD

• Target Voltage Detected: 3.12 V

What I’ve Tried:

• Verified SWD wiring (SWDIO, SWCLK, GND, VCC)

• BOOT0 set to 0 (boot from flash)

• Checked for power on the board

Question:
What else should I try to get the MCU detected? Could this be a clone ST-Link V2 issue, or something else with my MCU or wiring?

Any help is appreciated — thank you!

[Imen.D]

Hello @RShashank and welcome to the Community,

Please have a look at this article which describes tips to fix errors encountered when connecting the STM32 target board to your computer: How to solve connection errors when connecting and programming the STM32 target board

[TDK]

Is this a custom board? Show the schematic.

Perhaps also show a picture of the setup with connections between board and programmer.