private function provideXML($amount = null)
{
$xml = '<?xml version="1.0"?>
<ncresponse
orderID="5"
PAYID="33146134"
PAYIDSUB=""
NCSTATUS="0"
NCERROR="0"
NCERRORPLUS="!"
ACCEPTANCE="test123"
STATUS="91"
ECI="7"
AMOUNT="' . ($amount ? $amount : '4.5') . '"
CURRENCY="GBP"
PM="CreditCard"
BRAND="VISA"
CARDNO="XXXXXXXXXXXX1111"
IP="127.0.0.1">
</ncresponse>';
return $xml;
}