yes its a shield, arduino underneath.
arduino gets power from MM, which at rhe moment gets only those 20V.
yes i set In1 and In2, and i get correct direction feedback from the indicator leds on the MM. and i get carious different voktages depending on what i send, but always 15V to little.
so i guess that the MM is fine & well fed with the 20V & GND, and it also drives the arduino, since it works without USB connection.
do you get higher voltage in & out?
i will get a 5V supply to the MM tmrw and try...
any other ideas?