I'm building an enchanting room where the books come up when you enter and go down when you leave. I've figured out how to hook up the redstone so that the books are up while you stand on a pressure plate, which is very easy. However, I want it to stay up after you step on the pressure plate once, and go down when you step on it again. I can't figure out how to make the signal stay until pressed again. Anybody have knowledge on how to do this?