Guys, I need a simple timer that will count down from 1-20 seconds and then have a continuous output of high to run a electric motor. And time can easily be adjusted (potentiometer?) Ive been playing with 555 timers and timer circuits from diagrams of "555 timer" through google, but all I can make it a pulse generator/Astable oscilator out of a 555. None of the timer cicuits work. The goal is to turn the circuit on, wait 2 seconds, run the motor, and turn off after 15 seconds, (but those times need to be adjustable)(and Ill run both the timers through an XOR gate to get the motor to shut off (because both will be high)) So can the 555 chip and a 7400 chip take 9 volts? Has to be breadboardable to any help will be much appreciated.