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can't find COM port on my PC.. (STM32F401RE board)

ckim
Associate II
Posted on December 08, 2015 at 08:39

Hi, I've been seeing COM2:STMicro... port on my PC but after I removed some drivers and installed some, it disappeared. Still I can connect to the target using ST-LINK/V2-1 utility and I can debug the code using uVision5.

What software should I install more? Any help deeply appreciated.

(By the way, I learned that I can update the firmware of the board using ST-LINK utility and did that hoping this could make the UART print work with uVision program installed.. But now I cannot connect to the COM port using tera-term...)

ADD : I can find the COM port but printf is not working. Before I remove a driver (winusb from STmicro), the UART test program worked. I cannot reproduce it.
3 REPLIES 3
Posted on December 09, 2015 at 15:05

Hi Chan,

In the STM32 STLink Properties, click on the device name, in properties click on ''Driver'' and ''Update Driver''. So, the Virtual COM Port will be re-installed. If you can not visualize it in the properties window, disconnect the board and reconnect it to the PC.

-Shahrzad-

ckim
Associate II
Posted on December 11, 2015 at 03:11

shahrzad,

You mean doing it in the win7 device manager? I did it there by selecting port(COM & LPT) /'' STMicroelectronics STLink Virtual COM Port(COM2)''. Selected ''Driver'' and ''Update Driver''. But it says newest driver is already installed. The test program that I received from clive1(USART2NUCLEO401.hex) worked couple of times but id doesn't now. Installing uVision5 makes it not work I guess.

Posted on December 11, 2015 at 05:29

I wasn't able to reproduce the failure by installing the various ST drivers. Not sure what Keil is installing but probably some mis-match of DLL and drivers.

These can be the occasional battles you have with Windows, and the myriad of different components that can be installed on systems in the field.

I think I have sufficiently demonstrated the hardware works, and what combinations of drivers/firmware also work.

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