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I'm using a Basys 3 FPGA board (Artix-7 family).

I'm powering the board using it's micro USB port to PC USB port and programming it through this as well (in the JTAG mode).

Question: Can I use the micro USB port's USB-UART Bridge functionality while using the same port to power the FPGA?

I don't even know how USBs work electrically speaking so my intuition says yes since I'm programming it through the same cable... obviously this cable must have multiple internal wires that aren't all suddenly dedicated to a constant power level if the same cable can program the board simultaneously.

I understand this may be a naïve question so bear with me - I'm a physics major teaching myself EE.

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    \$\begingroup\$ Your thumb drive is powered by the same USB port that it uses to communicate. But if you're designing a USB-powered FPGA system, be careful about the power requirements, particularly the requirement to limit power consumption to the level allowed by the host system. \$\endgroup\$
    – The Photon
    Commented Jul 9, 2021 at 23:50
  • \$\begingroup\$ Lots of dev boards are powered over USB. So long as they only need 500ma (USB 2) or 900ma (USB 3) they can be powered over USB. \$\endgroup\$
    – user1850479
    Commented Jul 9, 2021 at 23:51
  • \$\begingroup\$ Understood. I have a larger design I want to implement but for the moment I just want to practice communicating with my PC so there shouldn't be much resource usage on the FPGA to draw power. So I take it that your answer is yes, so long as your design doesn't require too much power? \$\endgroup\$
    – Andrew
    Commented Jul 9, 2021 at 23:57

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Yes. The web page how to use the board also confirms this:

The Basys3 board can receive power from the Digilent USB-JTAG port (J4)

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  • \$\begingroup\$ Yes, but the USB-UART bridge is attached to the same connector (J4). So can J4 be used to power and communicated simultaneously? Again, please forgive my ignorance. \$\endgroup\$
    – Andrew
    Commented Jul 10, 2021 at 0:00
  • \$\begingroup\$ Wait, I notice pin 1 of a USB is a +5 V and two other ports for Data according to Google so would I be correct in assuming this is how the USB powers and communicates simultaneously? \$\endgroup\$
    – Andrew
    Commented Jul 10, 2021 at 0:04
  • \$\begingroup\$ I already confirmed, yes. Like other people said in above comments, things like keyboards and mice also need power from the PC to work in order to transfer data, so this is how it works. \$\endgroup\$
    – Justme
    Commented Jul 10, 2021 at 0:05
  • \$\begingroup\$ Got it. Thank you \$\endgroup\$
    – Andrew
    Commented Jul 10, 2021 at 0:06

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