Error in initializing ST-LINK device in all boards

[AdoringLamb]

i have been using stlink v2 for a while now, but today it wouldn't connect with any of my stm32 boards the error mesage that apears is 

STMicroelectronics ST-LINK GDB server. Version 7.9.0

Copyright (c) 2024, STMicroelectronics. All rights reserved.

Starting server with the following options:

Persistent Mode : Disabled

Logging Level : 1

Listen Port Number : 61234

Status Refresh Delay : 15s

Verbose Mode : Disabled

SWD Debug : Enabled

InitWhile : Enabled

Target no device found

Error in initializing ST-LINK device.

Reason: No device found on target.

i have no clue what it could be, i tried in two different pcs with stm32 cube ide in the 1.17 and 1.18 version, i have tried updating the stlink software in the cube ide , in the programmer and in the st link utility, nothing is really working, the boards are fine cause i can connect them to the st programmer using usb.

Need help, Thanks

[AScha.3]

Is it genuine STM or V2 "stick" ?

Connect with CubeProgrammer and show, what its telling.

[AdoringLamb]

its a genuine stlink v2 

[AScha.3]

Ooo.. target : 0,52V - that cannot work !

power your target to 3v3 and try again. (or you forgot to connect the vcc sense to st-link ?)

[AdoringLamb]

thats weird cause its 3.3 v in the input

[Tesla DeLorean]

It's measuring the voltage at Pin 1/2 at the ST-LINK 20-pin header.

These are the VTarget that the ST-LINK uses to buffer the IO to the target MCU.

[AdoringLamb]

so, i need to change the connection to other pins?

[Tesla DeLorean]

Well, you NEED to power the interface, for sure. The error's complaining that the interface to the device is non-responsive.

You haven't really described WHAT you've wired, there's a picture I unpacked enough to see you didn't power the ST-LINK properly, which is consistent with the failure, provided you've connected SWDIO, SWCLK, NRST and GND properly

[AdoringLamb]

i have conected3.3v, gnd,swdio and swclk the first times, the green marks in the image, i have also tried adding reset pin with the mode in under reset, but still the same error, also tried conecting to an external power supply with gnd conected  and also with the usb also conected. I have always programed with just vcc gns and dio and clk and have no problem.today its when it stop working with all my boards, i have tried several like blue pill, black pill, stm32h723vgt6,stm32wb55cbu6 stm32go no one works at all, they can conect via usb to the cubeprogrammer and it works, but i need the debuger in the cube ide

[AScha.3]

Did you try other wires ? Try...

And check : just connect any powered board, only :  GND + 3V3  to st-link.

You should see the "Target voltage", when st-link is detected:

If not...st-link has a problem.