Have you got a schematic of the hardware side of what you're working on?
Nope - just stick an arduino output to a transistor gate (2N3904 or something should work) through a 1K or so resistor and connect the VCM to +V (something as low as 1.5V works but I'd go with 5V or higher) and the other side of the VCM to the transistor collector, transistor emitter to ground.
Mowcius