function chgImage(a,b,msg){
a.src=b.src;
return chgBar(msg);
}
function chgBar(msg){
 window.status=msg;
 return true;
}
function goURL(go_url){
 window.location.replace(go_url);
}
function code_display(nPos,nValor)
{
  for (var i = 0; i < formulario[nPos].options.length; i++){
    if (formulario[nPos].options[i].value == nValor){
      formulario[nPos].selectedIndex = i;
    }
  }
}