ST-Link not detected

[MrMfromK]

Hi Pavel,

I just installed swd and wrote a small program to start with. But it does not find my ST-Link V3 nor a STM32-Nucleo board. I found issue #15 which looked for all devices and copied that to my program, so I hav this now:

#!/usr/bin/env python3 
# coding: utf-8 

import sys
import swd
import usb


def main ():
    devices = []
    # dev = usb.core.find(idVendor = 0x0483, idProduct = 0x374B, iProduct = 0x5, find_all = True)
    dev = usb.core.find(find_all = True)
    for device in dev:
        devices.append (device)
        print (hex(device.idVendor), hex(device.idProduct), device.serial_number)
        
    STLink = swd.Swd (swd_frequency=4000000, serial_no='')
    print (STLink)


if __name__ == '__main__':
    sys.exit(main())    

it produces this output:

0x4f2 0xb613 None
0x4f2 0xb604 0001
Traceback (most recent call last):
  File "E:\Projects\Software\Python\PySWD_Test\source\PySWD_Test.py", line 22, in <module>
    sys.exit(main())
  File "E:\Projects\Software\Python\PySWD_Test\source\PySWD_Test.py", line 17, in main
    STLink = swd.Swd (swd_frequency=4000000, serial_no='')
  File "C:\Users\Martin\AppData\Roaming\Python\Python310\site-packages\swd\swd.py", line 15, in __init__
    driver = _Stlink(
  File "C:\Users\Martin\AppData\Roaming\Python\Python310\site-packages\swd\stlink\__init__.py", line 114, in __init__
    usb = _usb.StlinkUsb(serial_no, debug=debug)
  File "C:\Users\Martin\AppData\Roaming\Python\Python310\site-packages\swd\stlink\usb.py", line 222, in __init__
    raise NoDeviceFoundException()
swd.stlink.usb.NoDeviceFoundException

With the upper dev = ... line nothing is found
I changed idProduct to 0x374B (instead of 0x374F as in issue #15), because I found this value in Windows device manager.
I'm running Python 3.10 under Win 10
(also swd.Swd () does not accept a keyword argument 'logger': error message is :TypeError: Swd.init() got an unexpected keyword argument 'logger')

Thanks for any help
Martin

[pavelrevak]

what version do you use? is it latest?
in main branch is supported 0x374b: https://github.com/cortexm/pyswd/blob/master/swd/stlink/usb.py#L115

[MrMfromK]

Yes, the latest, I downloaded today.
Meanwhile I saw that windows device manager shows 0x374b for STM32 Nucleo board and 0x374F for ST-Link V3. But neither is found when I run the python script with the right value for the connected one.
Also I checked out usb.py and I found both values (and more).

[MrMfromK]

Hi Pavel,
what can I do to find the cause of this? Can I do some tests, output some data or so?
I am really keen on using pyswd for my project, so would like to get it running.
Thanks
Martin

[pavelrevak]

0x4f2 0xb613 None
0x4f2 0xb604 0001

these devices are not supported, what st-link do you have ? and what version is there ?
are these numbers really from st-link ?

[MrMfromK]

Hi Pavel, yes, it’s true, these are not ST-Link. Meanwhile I know a little more and can say that the problem is not a PySWD issue but a PyUSB one. It is PyUSB that does not find the devices. I will try from a Raspi and see if that works. Thanks for your help Martin

[pavelrevak]

Try to install drivers for ST-link, this will make access to these drivers from libusb (hope)

[MrMfromK]

Hi Pavel,
meanwhile I found time to install and test PySWD on a Raspberry Pi (Model 3B) and it works out of the box, STLink, a Nucleo in my case is found and I can read and set memory, thats what I tried so far.
Also I did a lot of research to get this working under windows but my current conclusion ist that there is only one way and that is to install libusb as a driver for the target STLink rendering it unaccessible for CubeIDE, CubeProgrammer and so on. So this is not a solution in most cases and that means PySWD will not work under windows. I'll be happy to learn and experience something different, but I really spent hours...
Anyway, thank you for providing PySWD I will use it on a Raspi.

Martin

[pavelrevak]

I have had also used it on windows.

drivers for ST-LINK add (enable) access for this USB device (it will install only .inf file)
libusb is library used for access to USB ports

[MrMfromK]

Hi Pavel,
please can you give more details about the process to setup the driver for an ST-Link. I looked into windows device manager, the entry of my ST-Link. It has a driver installed and also an .inf-file. I found this inf-file in C:\Windows\INF and it says it uses winusb.sys.
So where do I get the driver you mentioned and how to install it? And most important: will I then still be able to use say Cube-IDE for program upload and debug and PySWD alternately?
I'ld really love to get it running that way.
Thanks for any help
Martin

[pavelrevak]

I don;t have windows at home, so I can't test this, but if I remember, the process was to install:

• st-link utility from ST https://www.st.com/en/development-tools/stsw-link004.html
• libusb: https://github.com/libusb/libusb/releases extract and copy libusb-1.0.dll into Windows/System32 directory
• install pyusb from pip
• use recent python3
  not sure about these steps, I was used this some years ago

[MrMfromK]

Hi Pavel,
now I am a little further. I had to use Zadig to install the driver, I will report details later.
Now PyUSB is running also under Windows and I see a lot of USB devices. Among them my STLinkV3 and Nucleo boards for G07 and H7.
Unfortunatelly the lines
`
STLink = swd.Swd ()

print (STLink)

print (STLink.get_version ().str)
`
run fine only for the Nucleo G07
Nucleo H7 produces this output:

Traceback (most recent call last):
  File "E:\Projects\Software\Python\PySWD_Test\source\PySWD_Test.py", line 42, in <module>
    sys.exit(main())
  File "E:\Projects\Software\Python\PySWD_Test\source\PySWD_Test.py", line 35, in main
    STLink = swd.Swd ()
  File "C:\Program Files\Python310\lib\site-packages\swd\swd.py", line 15, in __init__
    driver = _Stlink(
  File "C:\Program Files\Python310\lib\site-packages\swd\stlink\__init__.py", line 123, in __init__
    _check_status(status)
  File "C:\Program Files\Python310\lib\site-packages\swd\stlink\__init__.py", line 56, in _check_status
    raise StlinkException(_com.StlinkCom.STATUS.MESSAGES[status])
swd.stlink.StlinkException: Get IDCODE error

and ST-Link V3 produces this output:
Traceback (most recent call last):
  File "E:\Projects\Software\Python\PySWD_Test\source\PySWD_Test.py", line 42, in <module>
    sys.exit(main())
  File "E:\Projects\Software\Python\PySWD_Test\source\PySWD_Test.py", line 35, in main
    STLink = swd.Swd ()
  File "C:\Program Files\Python310\lib\site-packages\swd\swd.py", line 15, in __init__
    driver = _Stlink(
  File "C:\Program Files\Python310\lib\site-packages\swd\stlink\__init__.py", line 114, in __init__
    usb = _usb.StlinkUsb(serial_no, debug=debug)
  File "C:\Program Files\Python310\lib\site-packages\swd\stlink\usb.py", line 210, in __init__
    raise NoDeviceFoundException()
swd.stlink.usb.NoDeviceFoundException

All three the same on windows and Raspberry Pi so I think it must be somewhere in the PySWD code.
Updating them to the latest ST-Link FW version did not change the bahaviour.

Can you help please, it seems success is getting closer...

Thanks a lot

Martin

[MrMfromK]

I think I should give you some details because that might help you further investigate in detail:
In some stackoverflow topic I read that one has to use Zadig to use libusb and so be able to talk to USB devices through PyUSB. So I did this with some Nucleo board
Also I read that you have to specify the libusb-file to use with
backendUsblib1 = libusb1.get_backend(find_library=lambda x: "C:\Windows\SysWOW64\libusb-1.0.dll")
(I have 64-bit Python, it does not work giving the file C:\Windows\System32\libusb-1.0.dll, although both file are in these places and are identical)
and then use PyUSB with
dev = usb.core.find(backend=backendUsblib1, find_all=True)
With the driver installed by Zadig suddenly I could see a lot of USB devices. And I can see all three ST-Link.
Also this was sufficient for the Nucleo G07 to run the line
STLink = swd.Swd ()
But not for the others.
Now I am not sure if swd.Swd () is using the same driver as given above, I guess not. How can I force swd.SWD() to use libusb1 and the driver in C:\Windows\SysWOW64\libusb-1.0.dll ?

Thanks for any help
Martin

[pavelrevak]

okay, swd.stlink.usb.NoDeviceFoundException means that your stlinkv3 is not supported
look here if your v3 is here (by ID_VENDOR and ID_PRODUCT):
https://github.com/cortexm/pyswd/blob/master/swd/stlink/usb.py
..from line 106

[MrMfromK]

yes I looked at these lines before and my STlink is 0x483 and 0x374F, so it is in your list.

[pavelrevak]

please provide me debug info with parameter -ddd also with command line which you used