in : io.Knob()
old : flow.Init(data=50)
mul : math.Compute(op="*")
add : math.Compute(op="+")
out : io.Print()
dimmer : io.PWM()

in.direction > mul.a
5 > mul.b

mul.result > add.a
old.out > add.b

add.result > old.in
add.result > out.token
add.result > dimmer.dutycycle

