Pa = 0;
Pmax = 1050;
Pmin = 320; // valeur à changer (voir aussi calque)
Speed = 20;
Decal = 50; // valeur à changer (placement vertical)
Target = "drag_remote";
Obj = document.getElementById(Target);

function bodyMovinInit() {
    if (Obj != null) {
        wcb();
    }
}

function wcb() {
    if (window.XMLHttpRequest) {
        if(document.all){
            Pa = document.body.scrollTop + Decal;
        } else {
            Pa = window.pageYOffset + Decal;
        }
    } else {
        Pa = document.body.scrollTop + Decal;
    }
    if (Pa < Pmin) {
        Pa = Pmin;
    } else {
        Pa += Speed;
    }
    if (Pa != Pmax) {
        Pa = (.1 * (Pa - Pmax)) + Pmax;
        Obj.style.top = Pa + "px";
    }
    Pmax = Pa;
    setTimeout('wcb()', 10);
}

if (isNavigatorOk()) {
    bodyMovinInit();
}