// Get fad control connected
function handleFadConnected(wait_state)
{
    var state = dim.state("FAD_CONTROL");
    if (state===undefined)
        return undefined;

    if (wait_state && wait_state.length>0 && state.name!=wait_state)
        return wait_state;

    //dim.log("BIAS_CONTROL: "+state.name+"["+state.index+"]");

    switch (state.name)
    {
    case "Offline":
        return undefined;

    case "Disconnected":
        console.out("Fadctrl in Diconnected... connect.");
        dim.send("FAD_CONTROL/START");
        return "Connected";

    // Do-nothing conditions
    case "Connecting":
        return wait_state;

    // Do-something conditions
    case "Configuring1":
    case "Configuring2":
    case "Configured":
        console.out("Fadctrl in Configure state... reset.");
        dim.send("FAD_CONTROL/RESET_CONFIGURE");
        return "Connected";

    case "Disengaged":
        console.out("Fadctrl in Disengaged... connecting.");
        dim.send("FAD_CONTROL/START");
        return "Connected";

    // Final state reached condition
    case "Connected":
    case "WritingData":
        return "";
    }

    throw new Error("FAD_CONTROL:"+state.name+"["+state.index+"] unknown or not handled.");
}