I am using Win10.  Has anyone had any trouble connecting a NanoVNA2 v4 to a PC?  I get the following USB error under Device Manager if I connect the NanoVNA before starting the QT software:
Unknown USB Device (Device Descriptor Request Failed)

When I click on that description it says:
Windows has stopped this device because it has reported problems. (Code 43)

A request for the USB device descriptor failed.

I tried multiple computers and see the same error.  I even tried to manually install the Cypress driver as Serial USB device since Windows was finding some Microsoft driver initially. Then, I get rid of the USB error and the QT software sees the COM port.  I select the COM port but the QT  gives me this error:

xavna_read_autosweep failed:  Resource deadlock avoided

Nothing seems to work.  The VNA has an operational screen with the traces and menus.  I cannot use the windows software anymore due to a USB error.  Any suggestions?   Do I need to JTAG or whatever with the STM?  Where is that process and the pin locations documented?   Can anyone confirm the Cypress driver hardware type:  Serial USB?

Thanks,
Mike

https://drive.google.com/file/d/1Ov6BbQd2-nMFFicU9IQicklIJpjNDWQX/view



On Tue, 29 Jun 2021, 19:05 Mike, AA9VI via groups.io, <mjswiatk=
yahoo.com@groups.io> wrote:

> I am using Win10. Has anyone had any trouble connecting a NanoVNA2 v4 to
> a PC? I get the following USB error under Device Manager if I connect the
> NanoVNA before starting the QT software:
> Unknown USB Device (Device Descriptor Request Failed)
>
> When I click on that description it says:
> Windows has stopped this device because it has reported problems. (Code 43)
>
> A request for the USB device descriptor failed.
>
> I tried multiple computers and see the same error. I even tried to
> manually install the Cypress driver as Serial USB device since Windows was
> finding some Microsoft driver initially. Then, I get rid of the USB error
> and the QT software sees the COM port. I select the COM port but the QT
> gives me this error:
>
> xavna_read_autosweep failed: Resource deadlock avoided
>
> Nothing seems to work. The VNA has an operational screen with the traces
> and menus. I cannot use the windows software anymore due to a USB error.
> Any suggestions? Do I need to JTAG or whatever with the STM? Where is
> that process and the pin locations documented? Can anyone confirm the
> Cypress driver hardware type: Serial USB?
>
> Thanks,
> Mike
>
>

that doesn't seem to work.  Does anyone have any other ideas?

Hi Mike,

I remember I had a similar problem, both on windows and Linux. Swapping the 2 USB data lines did the trick.
Does this help?
Yvan, ON4YVM

Hello Mike!
Have You driver for V2 devices installed?
https://nanorfe.com/downloads/NanoVNA-QT/CypressDriverInstaller_1.exe
73 de Vladimir, dl7pga

Hi Mike,
I have exactly the same problem - I have tried everything. The V2Plus4 I have is very reluctant to switch to USB mode when you connect to it with any of the available Windows software on either Windows 7 or Windows 10 with the Cypress driver. I managed to update the firmware posted that should have fixed this problem with Windows 10 when I did manage to get the USB MODE Serial Port working. When I monitor the VNA comms using *NanoVNA App V1.1.206* which has the facility to monitor the USB Comms I get:

47.630 connect: serial port connecting ..
47.630 connect: serial port connected
47.630 tx: leave USB data mode
47.630 tx: 00 00 00 00 00 00 00 00 20 26 02
47.630 tx: are you a V2 ?
47.630 tx: 0D
48.130 tx: leave USB data mode
48.130 tx: 00 00 00 00 00 00 00 00 20 26 02
48.130 tx: are you a V2 ?
48.130 tx: 0D
48.690 rx link timeout .. scanning for a NanoVNA V1 ..
48.690 tx:
49.190 tx:
49.690 tx:
49.750 rx link timeout .. disconnecting

Everything looks OK in Windows device manager both with the COM Port and USB to UART adaptor - both say they are using the digitally signed Cypress driver downloaded from https://nanorfe.com. Occasionally it will change to USB mode and connect to which ever software I am using and function OK for a while but then the USB comms fails but the device manager shows that both COM Port and USB to UART are OK. The functionality and operation of the V2Plus4 are normal on its internal display so the issue is clearly a problem with the USB port but as it enumerates OK then 2 way comms clearly is working and so there can be no crossover on the USB D+ and D- lines.
I purchased mine in April 2021 from the NanoRFE Store:

Version: NanoVNA V2Plus4
SN:35554252-00023333-34343034
Firmware: 20210530-412578c,
Build time Jul 26 2021 - 10:55:59
Occasionally it will switch to USB mode as shown on the internal display when the software connects to it. I am wondering if it's a bad batch of STM32F103C8/CB processors or some CPU timing issues being on the edge on USB port. I have inspected the main PCB and can't see any bad solder joints on either side of the PC board.

73 de Dave, G3XOU

Hi Mike,

Further to my last reply, I tried to connect to my VNA V2Plus4 this morning with NanoVNA Saver V 0.3.9 - it immediately crashed
So then I tried to connect to it with NanoVNA-App 1.1.206 and connected OK.

NanoVNA-App 1.1.206 USB Comms messages:

38.679 connect: serial port connecting ..
38.679 connect: serial port connected
38.739 tx: leave USB data mode
38.739 tx: 00 00 00 00 00 00 00 00 20 26 02
38.739 tx: are you a V2 ?
38.739 tx: 0D
38.859 rx: 32 .. ACK OK
38.859 tx: requesting device variant
38.859 tx: 10 F0
39.049 rx: 02 .. DEVICE VARIANT OK
39.049 tx: requesting serial protocol version
39.049 tx: 10 F1
39.169 rx: 01 .. PROTOCOL VERSION OK
39.169 tx: requesting hw-revision and fw-version
39.169 tx: 10 F2 10 F3 10 F4
39.369 rx: 04 ..... HARDWARE REVISION
39.369 rx: 01 02 .. FIRMWARE VERSION
39.369 rx: [connected to a V2]
45.358 tx: polling - requesting hw-revision and fw-version
45.358 tx: 10 F2 10 F3 10 F4
45.428 rx: 04 01 02 .. POLL OK
51.428 tx: polling - requesting hw-revision and fw-version
51.428 tx: 10 F2 10 F3 10 F4
51.548 rx: 04 01 02 .. POLL OK
57.428 tx: polling - requesting hw-revision and fw-version
57.428 tx: 10 F2 10 F3 10 F4
57.438 rx: 04 01 02 .. POLL OK

At this point I clicked on the Sweep button and the VNA internal display switched to NanoVNA V2Plus4 USB mode.

53.670 tx: polling - requesting hw-revision and fw-version
53.670 tx: 10 F2 10 F3 10 F4
53.740 rx: 04 01 02 .. POLL OK
05.740 tx: polling - requesting hw-revision and fw-version
05.740 tx: 10 F2 10 F3 10 F4
05.920 rx: 04 01 02 .. POLL OK
11.739 tx: polling - requesting hw-revision and fw-version
11.739 tx: 10 F2 10 F3 10 F4
11.800 rx: 04 01 02 .. POLL OK
17.740 tx: polling - requesting hw-revision and fw-version
17.740 tx: 10 F2 10 F3 10 F4
17.860 rx: 04 01 02 .. POLL OK
23.739 tx: polling - requesting hw-revision and fw-version
23.739 tx: 10 F2 10 F3 10 F4
23.739 rx: 04 01 02 .. POLL OK
29.739 tx: polling - requesting hw-revision and fw-version
29.739 tx: 10 F2 10 F3 10 F4
29.799 rx: 04 01 02 .. POLL OK
33.839 tx: setting scan parameters
33.839 tx: 00 00 00 00 00 00 00 00 20 30 00 23 00 50 C3 00 00 00 00 00 00 23 10 B6 1D 04 00 00 00 00 00 21 20 C9 00 21 22 01 00
33.839 tx: requesting 201 points ..
33.839 tx: 20 30 00 18 30 C9

I now clicked on the Disconnect button and the internal display stayed NanoVNA V2Plus4 USB mode.

I then ran NanoVNA Saver V 0.3.9 and connected to it successfully.

I then disconnected  and quit NanoVNA Saver V 0.3.9, unplugged the NanoVNA V2Plus4 USB cable at the PC end. Waited 10 seconds and reconnected it to the USB port, checked that the COM port and USB to UART were present in W10 Device manager and using the Cypress driver, again ran NanoVNA Saver V 0.3.9 and tried to connect to it - NanoVNA Saver V 0.3.9 immediately crashed and the NanoVNA internal display did not change to USB mode.
So then I tried to connect to it with NanoVNA-App 1.1.206 and connected OK.

As a mater of interest I also have a NanoVNA V2_2 and that works perfectly with NanoVNA Saver V 0.3.9 using the same USB COM Port and the Cypress drivers.

73 de Dave, G3XOU

Hi Dave,

I also have very similar problems to you using Win-7 and Win-10 (2 laptops), also XP.  Other than that, the units works 100% in stand-lone mode.
My V2Plus 4 version is 20201013 - 32077fd, build time Oct 13 2020, 04:35:10 and was purchased from the official store 6 months ago.

I can only connect reliably to the Nano-QT software.  All others either don't connect at all or only run for one sweep when the 'Continuous sweep' button is selected (aka NanoVNA v1.1.208 by OneofEleven).

I have changed the Nano's firmware to various other versions and ironically, they ALL connect to the Nano via USB on Win-7, but not tried with Win-10 ... yet.

I'm rapidly running out of hair to tear out ....  !!

Cheers,

Kitski
VK1LL

Only the QT software is officially supported and tested with every firmware release. NanoVNA-Saver v0.3.9 is known to be buggy; see if v0.3.8 works. Check if another program is trying to write to the serial port and try a different PC with Windows 7, Linux, or Mac.

Hello,

i have exactly the same problem with one of my two devices (NanoVNA V2Plus 4, version: git-202110530-412578c).
Cant get it back to work.
Did someonw find a fix for that issue?
Is there any hardreset i can perform or somethink like this?

Johnnyjokl