if (cmd == CHK_ISOL_ALLE)
{
  tvsign_type_t *tvsign = &Tv.Tgv[x].TvSign[0];

  for (int t=0; t<NUM_OF_TV_SIGN_ELEMENTS; t++)
  {
    if (tvsign[t]->Type == EOD) break;

    isol_type_t *isol = &tvsign[t].isol[0];

    for (int u; u<NUM_OF_ISOL_ELEMENTS; u++)
    {
      if (isol[u]->Nr == EOD) break;

      if (bs_afl_isol(Tv.BsBl, isol[u]->Nr) != 0) return false;
    }
  }

  return true;
}