php dio_开放函数拒绝端口访问

我目前正在使用考勤管理系统，该系统要求我使用RFID标签为学生打卡，这需要接收和发送数据。我正在使用dio_open Function来连接COM端口，但我不断收到错误

警告：dio_open（）：无法打开带有标志2和权限0的文件COM5:第42行的C:\wamp64\www\SerialPortTest.php中的参数无效

我正在使用PHP7.2.18，在windows上安装了wamp。请注意，这是我在下面使用的代码：

<?php
//phpinfo();
//-- settings --//

//brainboxes serial ports
//on 'nix start with cu.usbserial-
//on windows starts with com : must be lower case in windows and end with a colon
$portName = 'com9:';
$baudRate = 9600;
$bits = 8;
$spotBit = 1;

header( 'Content-type: text/plain; charset=utf-8' ); 
?>
Serial Port Test
================
<?php


function echoFlush($string)
{
    echo $string . "\n";
    flush();
    ob_flush();
}

if(!extension_loaded('dio'))
{
    echoFlush( "PHP Direct IO does not appear to be installed for more info see: http://www.php.net/manual/en/book.dio.php" );
    exit;
}

try 
{
    //the serial port resource
    $bbSerialPort;
    
    echoFlush(  "Connecting to serial port: {$portName}" );
    
    if (strtoupper(substr(PHP_OS, 0, 3)) === 'WIN') 
    { 
        $bbSerialPort = dio_open($portName, O_RDWR );
        //we're on windows configure com port from command line
        exec("mode {$portName} baud={$baudRate} data={$bits} stop={$spotBit} parity=n xon=on");
    } 
    else //'nix
    {
        $bbSerialPort = dio_open($portName, O_RDWR | O_NOCTTY | O_NONBLOCK );
        dio_fcntl($bbSerialPort, F_SETFL, O_SYNC);
        //we're on 'nix configure com from php direct io function
        dio_tcsetattr($bbSerialPort, array(
            'baud' => $baudRate,
            'bits' => $bits,
            'stop'  => $spotBit,
            'parity' => 0
        ));
    }
    
    if(!$bbSerialPort)
    {
        echoFlush( "Could not open Serial port {$portName} ");
        exit;
    }
    
    // send data
    
    $dataToSend = "HELLO WORLD!";
    echoFlush( "Writing to serial port data: \"{$dataToSend}\"" );
    $bytesSent = dio_write($bbSerialPort, $dataToSend );
    echoFlush( "Sent: {$bytesSent} bytes" );
    
    //date_default_timezone_set ("Europe/London");
    
    $runForSeconds = new DateInterval("PT10S"); //10 seconds
    $endTime = (new DateTime())->add($runForSeconds);
    
    echoFlush(  "Waiting for {$runForSeconds->format('%S')} seconds to recieve data on serial port" );
    
    while (new DateTime() < $endTime) {
    
        $data = dio_read($bbSerialPort, 256); //this is a blocking call
        if ($data) {
            echoFlush(  "Data Recieved: ". $data );
        }
    }
    
    echoFlush(  "Closing Port" );
    
    dio_close($bbSerialPort);

} 
catch (Exception $e) 
{
    echoFlush(  $e->getMessage() );
    exit(1);
} 



?>