Serial Port to PHP - php

Question

I'm new to working with the serial port module to read data from devices and I'm trying to read data from an electronic balance through Nport W2150a device using php with the php_dio module, the code is outputing but the result is printing with unknow charset. What should I do to change that?
Output:
Code:
<?php
$portName = 'com1:1';
$baudRate = 9600;
$bits = 8;
$spotBit = 1;
header( 'Content-type: text/plain; charset=utf-8' );
?>
<?php
function echoFlush($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
{
$bbSerialPort;
echoFlush( "Connecting to serial port: {$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" );
$runForSeconds = new DateInterval("PT10S");
$endTime = (new DateTime())->add($runForSeconds);
echoFlush( "Waiting for {$runForSeconds->format('%S')} seconds to recieve data on serial port" );
while (new DateTime() < $endTime) {
$data = dio_read($bbSerialPort, 256);
if ($data) {
echoFlush( "Data Recieved: ". $data );
}
}
echoFlush( "Closing Port" );
dio_close($bbSerialPort);
}
catch (Exception $e)
{
echoFlush( $e->getMessage() );
exit(1);
}
?>