Someone please tell me, is it possible to supply external voltage to USB port
and detect this through an application running on the system. or else convert
externally supplied voltage to data and input it to USB so that running application
would detect it.
Yeah I want to supply voltage to USB port of a PC from an external voltage source. So, that it could be detected like a mouse click.
This is similar to what we can do from LPT port from pin 17.
you need an adapter of some sort, e.g. a USB serial converter (**broken link removed**). You can send the voltage into CTS, DSR or RXD (as a break condition) which can be detected by your program after it opens the serial port. There are also other USB breakout boards available to provide a similar functionality, albeit for a much higher cost.