Waveform Editor / Color Effect

Hey, right now I'm trying to do an Blue/Amber Color FX with Hue and Saturation parameters.
Saturation at 100%
FX on Hue: Stepform with Size of 80 between 240° and 400° (40°)
In result this gives me a Stepping Blue/Amber FX. But I want it more to fade between Blue and Amber, but a Sinewave is too much fade.
What I would need is an attack/decay parameter for the Step form.

Is there any other possibility to fade between the 2 values?

Thanks