Слушалка купюрника

<?php

require_once 'com.php';
require_once 'trait.functions.php';
require_once 'class.q_api.php';

class mv {

    use functions;

    private $q_api;

    public function __construct() {

        $this->serial = new phpSerial();
        if (!$this->serial->deviceSet("/dev/ttyS5")) {
            die('Не удалось подключиться');
        } else {
            $this->serial->confBaudRate(19200);
            $this->serial->confParity("none");
            $this->serial->confCharacterLength(8);
            $this->serial->confStopBits(1);
            $this->serial->confFlowControl("none");
            $this->serial->deviceOpen();
        }
        $this->q_api = new q_api();
    }

    public function cmREBOOT() {
        $command = $this->sign_crc16([0x02, 0x03, 0x06, 0x30]);
        $this->printhex($command);
        $d = '';
        foreach ($command as $val) {
            $d.=pack('c', $val);
        }
        $this->serial->sendMessage($d);
        $this->read_fp();
    }

    public function cmBILL_TYPE() {
        $command = $this->sign_crc16([0x02, 0x03, 0x0C, 0x34, 0xFF, 0xFF, 0xFF, 0x00, 0x00, 0x00]);
        $this->printhex($command);
        $d = '';
        foreach ($command as $val) {
            $d.=pack('c', $val);
        }
        $this->serial->sendMessage($d);
        $this->read_fp();
    }

    public function cmEOT() {
        $command = $this->sign_crc16([0x02, 0x03, 0x06, 0x00]);
        $this->printhex($command);
        $d = '';
        foreach ($command as $val) {
            $d.=pack('c', $val);
        }
        $this->serial->sendMessage($d);
        $this->read_fp();
    }

    public function cmPOOL() {
        $command = $this->sign_crc16([0x02, 0x03, 0x06, 0x33]);

        $pool_command = '';
        foreach ($command as $val) {
            $pool_command.=pack('c', $val);
        }


        while (true) {
            $bill = 0;
            $ret = false;
            $this->serial->sendMessage($pool_command);
            $this->printhex($command);
            $ret = $this->read_fp();
            $rs = count($ret);
            if ($rs == 0) {
                die('Ошибка чтения.');
            } else {
                if ($rs == 6) {
                    switch ($ret[4]) {
                        case 0x19://DISABLED
                            $this->cmBILL_TYPE();
                            break;
                    }
                } elseif ($rs > 6 && $ret[4] == 0x81) {
                    switch ($ret[5]) {
                        case 1:
                            $bill = 200;
                            break;
                        case 2:
                            $bill = 500;
                            break;
                        case 3:
                            $bill = 1000;
                            break;
                        case 4:
                            $bill = 2000;
                            break;
                        case 5:
                            $bill = 5000;
                            break;
                        case 6:
                            $bill = 10000;
                            break;
                        default:
                            $bill = 0;
                    }
                    $repeat = false;
                    $send = false;
                    for ($k = 0; $k <= 3; $k++) {
                        if (!$repeat) {
                            $bill_res = $this->q_api->send_bill($bill);
                        }
                        if ($bill_res > 0) {
                            usleep(2000*1000);//Две секунды крепкого, здорового сна
                            $bill_res = $this->q_api->send_bill($bill, $bill_res);
                            $repeat = true;
                        } else {
                            $this->cmEOT();
                            $send = true;
                        }
                    }
                    if(!$send){
                        //Ложим демон, нет связи с сервером.
                        die();
                    }
                }
            }
            usleep(1000 * 1000); //Дрыхнем секунду.(1000мс)
        }
    }

    /**
     * Чтение с порта.
     * @return array Массив байт ответа.
     */
    function read_fp() {
        $start = $this->microtime_float();
        $read = $this->serial->readPort();
        while (($read == '') && ($this->microtime_float() <= $start + 10.5)) {
            $nread = $this->serial->readPort();
            if ($nread != '') {
                $read .= $nread;
                $nread = '';
            }
        }
        $ret = unpack("c*", $read);
        foreach ($ret as &$v) {
            $v = abs($v);
        }
        $this->printhex($ret, '<<:');
        return $ret;
    }

    function __destruct() {
        $this->serial->deviceClose();
    }

}