Weird FTDI/Datalogger problem - Page 1
Forum section: electronics / general

author: CJay
author_rank: Super Contributor
timestamp: December 14, 2016, 03:03:01 pm
content: Work related but today I ran across a problem with a datalogging current clamp, the device in question has a USB port on it which is implemented using an FTDI chip (I think FT232).Plugging it into a freshly built Windows 7 laptop and installing the drivers from disk allows the clamp to be recognised and work with the supplied application but after a reboot, power down or removal/reinsertion of the device Windows pops up a message 'USB Device Unrecognised' and after that no amount of effort will persuade it to work, trying to reinstall the drivers manually etc...There is no problem with the Win 7 install or laptop hardware, it recognises USB HID, Mass storage etc. with no problems, but this data logger and several others of exactly the same model all exhibit this problem on several laptops.Could it be a symptom of FTDIGate or am I being overly suspicious?

author: Fortran
author_rank: Regular Contributor
timestamp: December 14, 2016, 03:48:38 pm
content: I've had the exact same symptom on one of my boards with an FTDI.I don't have the schematics at hand, but I think it was the FT231XQ. Straight from Digi-Key so I don't think it was counterfeit.Only tested it in W7 and W10 though.There might be an issue running Vcc at 5V and RX/TX at 3.3V (lots of notes regarding that, might have screwed up), but I never got further then speculating.Was still in design stage and I had enough room so I cut my losses and slapped on a FT232RL instead.Those always seem to work no matter what you do to it.

author: Karel
author_rank: Super Contributor
timestamp: December 14, 2016, 04:46:11 pm
content: Connect it to a running Linux system, open a console and enter dmesg.Check if the VID and PID numbers are correct.You should see something like this:Code:[29896.289238] usb 2-1.6: new full-speed USB device number 3 using ehci-pci[29896.380802] usb 2-1.6: New USB device found, idVendor=0403, idProduct=6001[29896.380806] usb 2-1.6: New USB device strings: Mfr=1, Product=2, SerialNumber=3[29896.380808] usb 2-1.6: Product: TTL232R-3V3[29896.380811] usb 2-1.6: Manufacturer: FTDI[29896.380812] usb 2-1.6: SerialNumber: FT930X2O[29897.459600] usbcore: registered new interface driver usbserial[29897.459626] usbcore: registered new interface driver usbserial_generic[29897.459641] usbserial: USB Serial support registered for generic[29897.465435] usbcore: registered new interface driver ftdi_sio[29897.465453] usbserial: USB Serial support registered for FTDI USB Serial Device[29897.465514] ftdi_sio 2-1.6:1.0: FTDI USB Serial Device converter detected[29897.465555] usb 2-1.6: Detected FT232RL[29897.465557] usb 2-1.6: Number of endpoints 2[29897.465559] usb 2-1.6: Endpoint 1 MaxPacketSize 64[29897.465561] usb 2-1.6: Endpoint 2 MaxPacketSize 64[29897.465563] usb 2-1.6: Setting MaxPacketSize 64[29897.465999] usb 2-1.6: FTDI USB Serial Device converter now attached to ttyUSB0

author: tatus1969
author_rank: Super Contributor
timestamp: December 14, 2016, 05:11:58 pm
content: try putting a usb hub with own supply into the loop, if it works well then i would suspect a supply problem.

author: TimCambridge
author_rank: Regular Contributor
timestamp: December 18, 2016, 11:47:27 am
content: The first thing I would try would be the Microsoft USBView utility. It's on the FTDI site:http://www.ftdichip.com/Support/Utilities/usbview.zipThat will tell you for sure whether Windows can see your device and what the VID/PID are set to.If that is OK, unplug the your deviice and run "CDM Uninstaller", also available on the FTDI Utilities page. That should get rid of any old drivers lurking on your system. Then replug and now you should definitely be using the latest drivers.--Tim

author: CJay
author_rank: Super Contributor
timestamp: December 19, 2016, 09:20:25 am
content: In no particular order...It's a Microsoft exclusive business, would be difficult for me to plug it into a Linux system.It's a self powered device which draws no power from the USB.I'm not able to strip the device down to examine it as it's sealed with calibration and approval stickers.I will try the USBView utility as that sounds the easiest way to find out what's going on and I'll also try the CDM Uninstaller next time I'm able to track down the user.No guarantees but I will try and post back results.

author: senso
author_rank: Frequent Contributor
timestamp: December 19, 2016, 05:30:14 pm
content: A usb pen/drive with a live boot ubuntu/something related is always handy when you are around computers, no need for VM's, nor dual booting, just plug the usb pen, reboot and you are into linux world.

author: CJay
author_rank: Super Contributor
timestamp: December 19, 2016, 06:08:45 pm
content: It would be but these machines are locked down to prevent bootng from anything other than the hard drive or network and Bitlocker gets very upset if it works out that it's been asked to boot from something else.I do however have a possible solution that will allow me to investigate the problem which involves a retired PC and a bootable ISO so hopefully, if the loggers haven't gone off shore I can investigate further soon

author: elecman14
author_rank: Unknown
timestamp: December 22, 2016, 09:27:38 pm
content: Quote from: CJay on December 19, 2016, 09:20:25 amI was going to suggest Windows Subsystem for Linux but it appears that it does not support lsusb. Running Linux on top of windows strips all the fun stuff out.