Hi

I've a SAA2N from Zeenko (see picture) that is impossible to connect PC, as the USB is not recognized (USB ID 0x0000 0x0000), consequently it can't be upgraded or used with any PC software.

I've already checked any posible short-circuit between D+ and D- lines from USB to the GF32F303 and there is no issue there, as a similar problems was already commented in a 2 years ago message.

Any IDEA of what can be the problem?
Can be the problem related with resistor R338 (1K5) from USB-DP to VDD or the capacitor C328 (470nF) decoupling VDD. Measuring the resistor without power supply and without USB connection measures correctly 1.5 Kohms.


Can I write the USB ID code in the GD32F303 using an ST link properly connected to the ISP connector on the PCB? Or the only options is to put a new GD32F303 and reprogram again completely?

Thanks in advance for the help and guidance.

Alex
EA4BFK

It is recommended that you first change a USB cable to retest, it may simply be a poor contact with the USB cable.

Hugen

I've tested 5 different USB A - USB Micro cables, that work perfectly with other SAA2 and none of them work with the unit I have the problem, the USB remains Unknown.

Also I've measured the continuity and potential short-circuits among the data lines, and all is ok.

Any solution available?

Alex

Any new idea or proposal to solve the issue of USB Unknown Device problem?


Alex

You are sure about the usb cable??
I had a few "charge only" cables here flying around... Those are driving you nuts if you do not charge your phone but want to connect a device to the pc.
Drivers installed?
Greetz sigi dg9bfc

Am 23.06.2022 18:58 schrieb ea4bfk <fernandezponce.alejandro@...>:

Hi Sigi

Yes all the cables I've used I already tested before with other SAA2 units and work perfectly.

Alex

Hugen et all

There is any known solution to this problem?

Alex

EA4BFK

Buy a new VNA

Sent from AT&T Yahoo Mail on Android

On Thu, Jun 30, 2022 at 5:47 PM, ea4bfk<fernandezponce.alejandro@...> wrote: Hugen et all

There is any known solution to this problem?

Alex

EA4BFK

David

Thanks for your constructive comment, but before buying a new one, I have follow other ways.

With ST-Link and STM32Cube Programmer I´ve been able to communicate with the GD32F303 (See Figure 1), It shows the Device ID is 0x414, what I would expect in the USB ID on windows, but it continious to be considered Unkonw Device.

With ST-Link I' ve upload the bootloader (binary.bin) at adress 0x08000000 succesfully , but no change on the USB Unknown. (file from https://github.com/DiSlord/NanoVNA-V2-firmware/tree/master/bootloader).

I've also tried to upgrade the firmware uploading from adress 0x08004000, the files SAA2-220225.bin and alternatively SAA2N-220225.bin, but not upload possible as it shows an error in the process, and now I've a white screen :-(.

Figure 3, is picture of the GD32F303, and my suspicion is thet is a faulty device in some way.

Any suggestions on how to proceed?

Thanks

Alex
EA4BFK

Have you tried connecting your Nano to any other machines? If ST link talks to it, there may be something peculiar about the setup in your Windows computer. Are you connecting through a hub for convenience? I don’t think that would do it but when all else fails, you need to start thinking crazy thoughts.

John, KD6VKW

I was seduced by the low prices on these gadgets. The people who sell them are under a great deal of competitive pressure which encourages them to take short cuts which adversely affect quality and reliability. They have no concept of product support. Just try to return a DOA and they claim it was never received and perhaps that is true. There is a program called RoHS (reduction of hazardous substances) and I have heard rumors that they will be removing lead from solder. This guarantees future failures. There is a great deal of confusion caused by clones causing users to upgrade with the wrong firmware. My gadgets made in UK & USA still work.

Sorry to piss in your ears since I perceive the problem is we are all buying junk.

Probably, unless you buy from the original store. But the warnings are out there for this product and the TinySA and yet people still buy junk from clone vendors disregarding the warnings because they might save a buck or two. I don't have compassion for people not doing due diligence when buying stuff.

I have bought many of those items, for different projects and to give away to students. I always buy from the official outlets and never had any problem.

While I don't believe this will solve everyone's issue with USB errors, I have found this solved mine.

After hours of trying many different computers with all kind of settings, (drivers, registry edits, different USB cables) I noticed that the device was recognized once every 10 reboots (very frustrating). I also noticed that once it did run and I loaded VNA-QT the software would work for a little while then crash.

I believe that this was spurious noise on the USB preventing the computer from communicating to the VNA. I placed several toroids on the USB cable and POOF...Consistent, reliable operations!

For those that don't know these are, they are the little round "bumps" in the cables you see on such devices like Monitors and power supplies.

My suggestion is buy a HIGH Quality USB Cable with torrois suppression - OR - buy a few clamp on toroids (https://www.amazon.com/ferrite-chokes/s?k=ferrite+chokes) and give it try!!!!

GOOD LUCK - (let me know you results..)

Good catch and you can also use a specific USB 2.0 isolation transformer designed for USB applications. It filters the signal through a transformer but if you don’t want to buy toroids or USB isolation transformers, practically any USB WiFi device, bridge, WiFi extender or even Ethernet devices has Ethernet isolation transformers and USB isolation transformers that will work just fine. I have used Ethernet and USB parts from routers, old NIC’s, switches, firewalls, access points, laptops and more. A simple isolation box consisting of a transformer and clean 5V separate from the laptop has solved countless issues with computers and anything RF. I use Apple and that has helped with non-RF issues although not all software is cross compilable.

Great tip, thank you!


On Sun, Sep 11, 2022 at 6:27 PM, Dave Bisciotti via groups.io<dbisc@...> wrote: While I don't believe this will solve everyone's issue with USB errors, I have found this solved mine. 

After hours of trying many different computers with all kind of settings, (drivers, registry edits, different USB cables) I noticed that the device was recognized once every 10 reboots (very frustrating).  I also noticed that once it did run and I loaded VNA-QT the software would work for a little while then crash. 

I believe that this was spurious noise on the USB preventing the computer from communicating to the VNA.  I placed several toroids  on the USB cable and POOF...Consistent, reliable operations!

For those that don't know these are, they are the little round "bumps" in the cables you see on such devices like Monitors and power supplies. 

My suggestion is buy a HIGH Quality USB Cable with torrois suppression - OR - buy a few clamp on toroids (https://www.amazon.com/ferrite-chokes/s?k=ferrite+chokes) and give it try!!!!

GOOD LUCK - (let me know you results..)

I did this AND powered my USB hub from a linear supply instead from a switching supply. This solved all my crashing problems with software for the NanoVNA and TinySA. It also resulted in a whole bunch of less spurs displayed in the TinySA.

It is obvious that there are many potential causes, each with its own solution to this problem. I'll relate my recent experience. I believe the micro-USB connector developed a problem.

I have a Zeenko SAA2N that I've been using without problem for the last 2 years. I used it about 3-weeks ago to measure TDR on some coax cables. It worked flawlessly. I decided I might try the latest DisLord firmware, and now the Windows 10 PC kept throwing the dreaded "Unknown US Device (Device Descriptor Request Failed)" message anytime I tried to connect the unit. I checked four different USB cables, all of which were successful in connecting to micro-USB SDR radios, so I know the cables were functional. I put multiple ferrite cores on the cables. I uninstalled and reinstalled the Cypress and STMicro drivers. Nothing worked. I even tried everything on a different PC. No success.

I disassembled the unit and disconnected the internal cables to look for solder blobs, cold solder joints, etc. on the USB connections. I didn't see anything. Battery voltage was about 3.65 VDC. I reassembled, and connected the USB cable to a USB charger. Then I noticed the single red connect-LED came on, but the three charging LEDs did not cycle. I noticed if I repositioned the micro-USB plug, the charging LEDs would cycle. I propped up the unit to put pressure on the connector, and was able to achieve a full charge on the battery (all LEDs solid illumination). I tried connecting again on two PCs to no avail. However, once I found the right pressure, and squinted my left eye and bit on the right side of my tongue while elevating my left leg (just kidding), I received a successful USB-UART display in the Device Manager. I was then able to flash the new firmware, and use various NanoVNA software programs to connect to the device.

It is obvious that my issue is an intermittent connection in the micro-USB socket on the unit. Alas, my eyesight isn't what it used to be, even with an illuminated bench magnifier, and my hands aren't steady enough to re-solder millimeter-pitch connections. But I was able to achieve my goal of flashing new firmware into the device.

I just wanted to relay my experience to illustrate that there can be multiple reasons for the failure to connect, and there is no one-size-fits-all solution. What works for one person may not work for another.

Good luck!

Ken -- WBØOCV

I should also mention that I tried multiple on-board USB ports (no USB hubs) on both PCs, and also spritzed both the male and female USB connectors with 91% isopropyl alcohol along with several insertion/removal cycles to ‘clean’ the contacts, all to no avail. There is most certainly a trial-and-error “sweet” spot in angling/pressuring the USB plug to obtain a successful connection in my situation. I just attempted a ‘casual’ connection to the PC, and got the connection error until I got the achieved the proper alignment for connection.

Ken

From: Ken Sejkora
Sent: Monday, September 26, 2022 06:42 PM
To: NanoVNA-V2@groups.io
Subject: Re: [NanoVNA-V2] USB Unknown Device problem

It is obvious that there are many potential causes, each with its own solution to this problem. I'll relate my recent experience. I believe the micro-USB connector developed a problem.

I have a Zeenko SAA2N that I've been using without problem for the last 2 years. I used it about 3-weeks ago to measure TDR on some coax cables. It worked flawlessly. I decided I might try the latest DisLord firmware, and now the Windows 10 PC kept throwing the dreaded "Unknown US Device (Device Descriptor Request Failed)" message anytime I tried to connect the unit. I checked four different USB cables, all of which were successful in connecting to micro-USB SDR radios, so I know the cables were functional. I put multiple ferrite cores on the cables. I uninstalled and reinstalled the Cypress and STMicro drivers. Nothing worked. I even tried everything on a different PC. No success.

I disassembled the unit and disconnected the internal cables to look for solder blobs, cold solder joints, etc. on the USB connections. I didn't see anything. Battery voltage was about 3.65 VDC. I reassembled, and connected the USB cable to a USB charger. Then I noticed the single red connect-LED came on, but the three charging LEDs did not cycle. I noticed if I repositioned the micro-USB plug, the charging LEDs would cycle. I propped up the unit to put pressure on the connector, and was able to achieve a full charge on the battery (all LEDs solid illumination). I tried connecting again on two PCs to no avail. However, once I found the right pressure, and squinted my left eye and bit on the right side of my tongue while elevating my left leg (just kidding), I received a successful USB-UART display in the Device Manager. I was then able to flash the new firmware, and use various NanoVNA software programs to connect to the device.

It is obvious that my issue is an intermittent connection in the micro-USB socket on the unit. Alas, my eyesight isn't what it used to be, even with an illuminated bench magnifier, and my hands aren't steady enough to re-solder millimeter-pitch connections. But I was able to achieve my goal of flashing new firmware into the device.

I just wanted to relay my experience to illustrate that there can be multiple reasons for the failure to connect, and there is no one-size-fits-all solution. What works for one person may not work for another.

Good luck!

Ken -- WBØOCV