Arty S7-50 COM port not showing up in Windows 10 Device Manager

[jb9631]

I've searched around a bit for a solution to this problem I've encountered recently but to no avail. My Arty board is perfectly usable, it is programmable from Vivado and debuggable. However, I cannot communicate to the host computer via UART, as the FTDI chip apparently isn't picked up by Windows. The RX LED flickers just fine on the board, but my operating system doesn't seem to be aware of the serial port.

In the meantime I am using a USB-UART Pmod that works just fine (detected by Windows), which is a workable solution, but I would prefer not using two USB cables per development board.

Any advice is much appreciated.

[jb9631]

This was a very strange thing indeed.

I tracked down a program from FTDI themselves called "FT Prog". After scanning for connected devices, this utility told me the Vendor and Product IDs of the FT2232H chip on my Arty S7 board, as well as its Serial Number and other properties.

Since searching for devices in Windows' own Device Manager is not possible, I downloaded a program named "USBDeview", which again scanned all devices connected to my computer (in the past or present). I was able to search for and find my board using the serial number obtained from FT-Prog. Then I right-clicked the entry and chose the "Uninstall Selected Devices" option.

After disconnecting and again re-connecting my Arty board, a COM port appeared in Device Manager as per usual.

I hope this adventure of mine saves any future tinkerers the time I needed to track down and fix the issue.

 

edit: Or perhaps not. The board then decided that the serial port was okay, but the other port used by Vivado was suddenly gone. I managed to use WSL2 to follow the instructions posted here to restore the FT2232 chip's EEPROM to some value that restores Vivado functionality to the board: https://gist.github.com/rikka0w0/24b58b54473227502fa0334bbe75c3c1

Edited June 28, 2022 by jb9631