I am adapting a design using a PIC32MX (which is actually working) to put an extra add-on. The add-on is a fingerprint reader which communicates via UART. Regarding that I have the USB pins exposed in my design, I found a way to connect a ftdi 3.3V (https://www.sparkfun.com/products/9716) between UART and USB. I am planning to connect my VCC ( 3.3V in my design , which I believe it can give me more than 200 mA) to the VUSB red wire cable. The other pins are straight forward.
So my questions from now are:
The purpose of the VBUS pin on the PIC32mx is to recognize if there's any device plugged or not, right? Is there any problem if I leave it not connected?
Do I need to connect the VBUSON pin to somewhere? I am already using for something else (the pin is shared/not dedicated).