Arty-S7 boards... randomly can't open serial port

[jaypdx]

I have two Arty S7 boards that are acting very strange.  When I plug them in they show up in the device manager as a COM port (one board shows up as two COM ports for some reason), and I can open each board in the Vivado Hardware Manager, but more than half the time I can't open the COM port (using Putty, hyperterm, etc.).   I've tried multiple computers, plugging directly into the computer USB port, various cables, etc., but I can't find a pattern or a reliable way to get them both working all the time.  It's quite frustrating.  Is this any sort of know issue with the Win10 driver or the FT2232 programming?  I've seen another thread that talks about reprogramming the FTDI part - is that something I should try?  I was corresponding with a Digilent engineer about this but he stopped responding... can anyone help?

 

Thanks!

 

[JColvin]

Hi @jaypdx

I apologize for the long delay.

I can provide the application, but I do not think it will work in your situation as the board is still correctly detected by the OS and is detected correctly by Vivado, though the new information about having tried multiple computers and cables is disconcerting. One board showing up as two COM ports is also unexpected; two USB Serial Converters (A and B ) under the Universal Serial Bus controllers dropdown in the Device Manager is expected as one is for the FTDI chip and the other for the serial (UART) communication.

What I might recommend trying instead (since I have been told that reprogramming working EEPROM isn't the best practice) would be to uninstall the driver, disconnect the FPGA, and then reconnect the FPGA; Windows should automatically reinstall the driver (maybe a restart is required, I'm not certain those sort of requirements from OS's). If not, you may need to reinstall it from FTDI driver from it's website: https://www.ftdichip.com/Drivers/D2XX.htm. I do not know if will resolve your problem, but from what you have described, it is a driver problem you are running into rather than an EEPROM problem with the device.

I will reach out to see if there is something else that I'm not considering.

Thanks,
JColvin

[jaypdx]

So I downloaded the FTDI uninstaller from https://www.ftdichip.com/Support/Utilities.htm#CDMUninstaller.  I run it against the Arty (VID=0403, PID=6010) and uninstalled all the drivers.  Then I rebooted and installed the latest FTDI drivers using https://www.ftdichip.com/Drivers/CDM/CDM21228_Setup.zip.  I plug in the Arty and get correct-looking entries in the device manager: one COM port + USB Serial Converter A+B.  I can connect to the board from the Vivado Hardware Manager but still cannot open the COM port in putty/teraterm.  

I'm going to email FTDI directly about this, but in the meantime I'm willing to try the EEPROM reprogramming if you can provide instructions on how to do that.

 

Thanks,

Jay

 

[JColvin]

Hi @jaypdx,

Oh, I would've just right-clicked on the driver listed in the device manager and selected "Uninstall", but I suppose that works as well. I don't recognize that exact download link for the FTDI drivers, but it's from ftdichip.com and has the correct driver number in the download name, so I presume it's correct.

I will send you the application in a PM.

Thanks,
JColvin