Good afternoon all,

Sorry this is a duplicate! Forgot to change the subject, ugh!

I've got a NanoVNA V2 Plus4 bought from the official source. 😄 It shows version git-20210530-412578c as the firmware installed.

I've been unable to update the firmware - and checking the archives plus using Google, I have not found any discussion of my exact problem. Here's what I've done and what I'm seeing:

I downloaded and installed the USB-CDC Cypress Driver installer from the Nanorfe webpage.

I then downloaded and can run NanoVNA-QT and am able to successfully connect to and control the NanoVNA - no problems. Normally, my computer sees the NanoVNA as COM9, as I'm running Windows 10. When I look at COM9's driver details, it shows a Cypress driver from the year 2015, which I believe is the one installed by the Cypress Driver.

When I follow the instructions in the online manual:

*** Connect the device to a PC using a USB cable.

*** Put the device into BOOTLOAD mode. This can be done from the device menu by selecting CONFIG →BOOTLOAD, and selecting RESET AND ENTER. BOOTLOAD mode can also be entered by holding down the JOG LEFT button on the device while it is powered off and on.

---> no problems here, I get the white screen. COM9 will disappear, and COM10 will appear, which I believe is proper . Again, looking at the driver details, it shows a Cypress driver from 2015.

*** The device should appear under the Device menu in NanoVNA-QT.

*** Click the device under the Device menu, for example /dev/ttyACM0.

---> COM10 does show up in the Device menu. When I click COM10 from the Device menu, I get one of two messages:

"Exception: Illegal byte sequence"

or

"Exception: No error"

This is where things end - I never get asked to select a firmware raw binary file. If go to devices and refresh, or click COM10 again in devices, it will do the same thing, either saying "No error" or "Illegal byte sequence."

Changing USB cables makes no difference. Changing USB ports (either thru a hub or direct to PC) doesn't make a difference. I've rebooted several times, and reinstalled the Cypress drivers multiple times. It doesn't matter if I change the method of entering the BOOTLOAD mode, either by holding down Jog Left on by selecting it from the CONFIG menu.

Kind of scratching my head as to what to do next?

Thanks much,
ben, kd5byb

Hi Ben,

I got this fix from Dave, VE3TLY, in an earlier post and this worked for me (on Win 10);

Under "Device", select "other"
Enter "\\.\Comxx" replacing "xx" with the COM port number (8, 10 etc.).

Then it will connect with no error. This com port issue only seems to be a problem with the newest version of QT.

73,
Gregg W7GRM

On 11/3/2022 7:11 AM, Gregg Myers wrote:
> I got this fix from Dave, VE3TLY, in an earlier post and this worked
> for me (on Win 10);
>
> Under "Device", select "other" Enter "\\.\Comxx" replacing "xx" with
> the COM port number (8, 10 etc.).
>
> Then it will connect with no error. This com port issue only seems to
> be a problem with the newest version of QT.

Hey Gregg and all,

Thanks much! I'll give this a try the next time I need to update firmware.

I did manage to get everything working this morning on a different Win10 PC without any issues. Put into boot loader mode, started QT, and it notices it's in firmware mode and asks if I want to update firmware, which I did. :) I have no idea why my main PC gives errors, but that the other, older, slower Win10 PC has no issues?

Strange!

thanks much and 73,
Ben, KD5BYB

AFAIK on Windows

If your assigned comport is numbered above 9 , you have to use the "\\.\Comxx" notation
Maybe you have had less Comports in use on the old one.

Carsten