When using special characters such as the tab placeholder "\t" in the split function, be careful not to escape the slash by adding a slah in front of it. To signify a tab, new line or carriage return use only one slash in front of the character. For example:
$cartes= "one\ttwo\tthree";
$tab_cartes = split("\t",$cartes );
$items = count($tab_cartes);
for ($x = 0; $x < $items; $x++)
{ echo $tab_cartes[$x] . "\n"; }