<?php
require_once('php_serial.class.php');

$serial = new phpSerial;
$serial->deviceSet('/dev/ttyUSB0');
$serial->confBaudRate(19200);
$serial->confParity("none");
$serial->confCharacterLength(8);
$serial->confStopBits(1);
$serial->confFlowControl("none");

$serial->deviceOpen();

while (true) {
    $data = $serial->readPort();
    if (strlen($data)) {
        for ($i=0; $i<strlen($data); $i++) {
            echo ord($data[$i]) . "\n";
        }
    }
}

$serial->deviceClose();
?>