Honored Contributor
Honored ContributorHello again,
The issue described above occurred again with my new DE0-nano-Board: I was programming several times the FPGA via the USB-JTAG-chain successfully and without fault. However since my last successful programming of the FPGA, the device is not recognized the Windows Device Manager. I was using and programming the SoC-nano for several weeks with an old computer (using a USB 2-port) without any problems. The fault of the USB-connection never occurred to me. However since I am using my new Notebook equipped with USB 3, the USB-JTAG-chain connection broke twice in two weeks. Apparently the USB-Microcontroller on the board is busted since this component installs the USB-Device to my computer-which now does not happen anymore. I checked the voltages on my DE0-nano board. They all have the expected values. Also when I power up the board no voltage-overshoots occur. So the only way to destroy my USB-Microcontroller is via the differential data-input (D+ & D-) of the USB-interface. From the physical Mini-USB-B port the only connection to the USB-Controller is the differential usb-data-signal. This differential signal is limited with a voltage protection device in parallel. As well the protection device and the USB-Controller are now broken. Since changing the programming-device from my Computer (USB 2) to a new Notebook (docking station with USB 3) is the only thing I changed since my USB-connection to the Board is corrupted, I suspect the new USB 3-port is the source of fault. So this is what I think happened: When programming the FPGA via the USB 3 port of my docking station voltage overshoots of the differential signal occured. After some programming the protection device is burst. So with the next voltage overshoot the USB-Controller broke as well. I checked the voltage level of the USB3 Port. Its value of 5,07V is normal. Does anyone programme his DE0-nano board via an USB3 port and is also encountering issues with the Mini USB-B port?
