<?php

	// declare variables
	$handle 	= $reply = null;
	$filename	= '/dev/ttyUSB1';
	$handle	= @dio_open($filename, O_RDWR | O_NOCTTY | O_NONBLOCK);

	// validate file handle
	if ( !is_file($handle) ){
		echo 'The device isn\'t detected';

	}else{ // main code.
               dio_fcntl($handle, F_SETFL, O_SYNC);

   dio_tcsetattr($handle, array(
  'baud' => 9600,
  'bits' => 32,
  'stop'  => 1,
  'parity' => 0));

		if ( dio_write($handle, 'AT') ) {
			echo 'Command is sent';
			$reply = dio_read($handle, 4);
			echo $reply;
			exit;

		}else{
			echo 'The device isn\'t read';
		}

		dio_close( $handle );
	}

	die;

?>