ok i understand that is a very vague question.. sorry for that.
on the fly, no schematic available.. best i can describe here..
lets say i have a simple 3x3x3 led cube, that wired common cathode per Layer.. 9 pins to anode.
im using the base of npn to "let" a layer light.
my friend (whos a coder) asked if i could make a pnp transistors work to close a ground circuit.
Not sure what benefit he has in mind, but, im just learning how to write c++ so im pretty green to all of this. Thanks for response!