Nexys4 DDR USB problem

[rzsmi]

For several months I have been using a Nexys4 DDR board on my Linux system for Vivado 2019.1 software development. A couple of days ago it Vivado would suddenly not recognize the board. A quick check in /dev/ttyUSBx shows the board did not register with the Linux OS. After deleting the rules file, I reinstalled the VIvado drivers. Still didn't register with /dev/ttyUSBx. Several cold reboots; nada. (Can't find the Digilent rules files)

Then I tried using a Cmod A7 on the same Linux system and it worked! Then I connected the Nexys4 board and two other Linux systems. one Vivado 2019.1 and the other 2918.2. Didn't work!

I appears the Nexys4 DDR board has a USB problem, altho the idle LED and display snake still function. I am wondering is there is any solutions to resolving this problem. Perhaps re-flashing the Nexys4 board? Did I miss something?

Many thanks in advance.

[JColvin]

Hi @rzsmi,

To double check, I presume you were using the same USB cable between the Nexys 4 DDR and the Cmod A7 (in the interest of ruling out a cable wearing out)? And since you didn't specifically mention it, does the Nexys board show up at all if you run lsusb with sudo?

Thanks,
JColvin

[rzsmi]

Yep, used the same cable when testing the Nexys 4 DDR and CmodA7. Tried the cable for my Analog Discovery 2 and had the same results. Hooked up my Zybo and it works too. Right now I am limping with the Zybo, but since the Zybo has been modified I would much rather go back to the Nexyx 4 DDR.

[JColvin]

Hi @rzsmi,

If it's not showing up with lsusb and the same cable is successfully being used with other boards, then I suppose the USB controller on the Nexys 4 DDR has become damaged somehow, though I'm not certain how this might have happened.

If you want, I can work with you to see about an RMA, though it will ultimately be the sales team decision (presuming you purchased it directly from Digilent as opposed to a distributor) if they decide to grant the RMA or not depending on when it was purchased.

Thanks,
JColvin