I have a robot 3volt car that goes when the lights go out. It stops running when the lights turn on. I would like to make it operate by sound. The problem with sound is you have to keep the sound constantly beeping or screening, so, so forth. You know the question that's coming, yes, how to make it keep going after first sound is detected, and how to make it stop on following sound. Simply, a beep makes it go, a second beep tells it to stop. Parts I have are: LM393 IC , two 3 volt motors, 2 transistors, PNP 5880. Plus have a sound shield the I made to easily accept other sensors. Do not want to us a Arduino programmable PCB. Can you help?