Arty Z7 20 Prog UART detected as 2 COM ports

[nics17]

Hi, 
I have just purchased a new Arty Z7 20. When I tried to flash it using the Prog Uart through Vitis, it failed. Upon further checking, turns out that every time I connected this board to my PC, it showed two COM ports. However, this is not the case for my other Arty Z7 boards.

If it helps I am using a USB hub to connect the board to my PC. Note that the other boards are also connected through the hub and are working fine.

Also, based on my test with PuTTY, only one of the two ports would display when I call the xil_print() function.

Even though it is still possible to flash the board using a microSD card. I still require the method to flash it through the Prog Uart. So, is there any way for me to solve this issue?

Thank you.

[JColvin]

Hi @nics17,

You are right that only one COM port should be associated with the Arty Z7-20.

I believe you should be able to fix it (presuming you are on Windows) by going into the Windows Device Manager, opening the Universal Serial Bus controllers dropdown, and going down to USB Serial Converter A. Go into its Properties, go to the Advanced tab, and uncheck Load VCP. This should remove the virtual COM port association with that particular sector (I don't know what the actual vernacular is offhand) from the FTDI chip, and leave you with just one working COM port (on USB Serial Converter B), and the ability to configure the board over the PROG/UART micro USB port.

Let me know if this doesn't resolve the issue and we can troubleshoot some more.

Thanks,
JColvin