var defile;// l'element a deplacer 
var psinit = 340; // position verticale de depart 
var pscrnt = psinit;       
function texteDefile() { 
   if (!defile) defile = document.getElementById('defile'); 
   if (defile) { 
     if(pscrnt < ( - defile.offsetHeight) ){ 
         pscrnt = psinit; 
                } else { 
         pscrnt+= -1; // pixel par deplacement 
      } 
      defile.style.top = pscrnt+"px"; 
   } 
} 
var timer = setInterval("texteDefile()", 50);//délai de deplacement