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ST link V2 not useable as UART on Windows 11

NDrag
Associate II

Hello all ! 

I have just purchased from the ST Micro web shop an STLink V2. I need this to change the firmware on a Dragino LAQ-4 air quality monitor, as recommended by Dragino.

In order to perform this upgrade, the ST Link has to be used with the STM32Cube Programmer, via the UART option.

The problem I am facing is that the Cube Programmer, when I select UART, shows No Comm port selectable. 

I run Windows 11 Home and, in the Device Manager, the ST link is correctly identified under Serial Bus Devices as STM32 STLink with no warning sign next to it. 

I have tried re-installing drivers, downloading STLink 009 driver package and installing that.. nothing works.

If I use the Cube Programmer, I can update the firmware of the ST Link itself with no issue. I have used the STLink utility (004) as well for upgrading and downgrading the STLink V2 firmware, again with no issue. 

The STM32Cube Programmer would not see it under UART and in Device manager, there is no Com port allocated. 

If I try to create a legacy port and go through the process and select ST Microelectronics Virtual port, the port created is there and selectable but unusable as Windows says: cannot start (error 10).

I am looking for some ideas and suggestions, please, if you have! 

All the best! 

10 REPLIES 10

@RobK1 wrote:

On their Wiki page, the LAQ-4 falls under the category "ST-Link v2 Upgrade", not "UART upgrade"


So it does!

And even the description for "UART upgrade" makes no mention of ST-Link.

There is no mention anywhere on that page of using an ST-Link for a UART update.

A complex system that works is invariably found to have evolved from a simple system that worked.
A complex system designed from scratch never works and cannot be patched up to make it work.