how to read data from serial port in php

1
2For Windows the Example 1 looks same this one:
3
4<?php
5
6exec('mode com1: baud=9600 data=8 stop=1 parity=n xon=on');
7// execute 'help mode' in command line of Windows for help
8
9$fd = dio_open('com1:', O_RDWR);
10
11while (1) {
12
13  $data = dio_read($fd, 256);
14
15  if ($data) {
16     echo $data;
17  }
18}
19
20?>
21
22

1<?php
2class Scanner {
3  protected $port; // port path, e.g. /dev/pts/5
4  protected $fd; // numeric file descriptor
5  protected $base; // EventBase
6  protected $dio; // dio resource
7  protected $e_open; // Event
8  protected $e_read; // Event
9
10  public function __construct ($port) {
11    $this->port = $port;
12    $this->base = new EventBase();
13  }
14
15  public function __destruct() {
16    $this->base->exit();
17
18    if ($this->e_open)
19      $this->e_open->free();
20    if ($this->e_read)
21      $this->e_read->free();
22    if ($this->dio)
23      dio_close($this->dio);
24  }
25
26  public function run() {
27    $stream = fopen($this->port, 'rb');
28    stream_set_blocking($stream, false);
29
30    $this->fd = EventUtil::getSocketFd($stream);
31    if ($this->fd < 0) {
32      fprintf(STDERR, "Failed attach to port, events: %d\n", $events);
33      return;
34    }
35
36    $this->e_open = new Event($this->base, $this->fd, Event::WRITE, [$this, '_onOpen']);
37    $this->e_open->add();
38    $this->base->dispatch();
39
40    fclose($stream);
41  }
42
43  public function _onOpen($fd, $events) {
44    $this->e_open->del();
45
46    $this->dio = dio_fdopen($this->fd);
47    // Call other dio functions here, e.g.
48    dio_tcsetattr($this->dio, [
49      'baud' => 9600,
50      'bits' => 8,
51      'stop'  => 1,
52      'parity' => 0
53    ]);
54
55    $this->e_read = new Event($this->base, $this->fd, Event::READ | Event::PERSIST,
56      [$this, '_onRead']);
57    $this->e_read->add();
58  }
59
60  public function _onRead($fd, $events) {
61    while ($data = dio_read($this->dio, 1)) {
62      var_dump($data);
63    }
64  }
65}
66
67// Change the port argument
68$scanner = new Scanner('/dev/pts/5');
69$scanner->run();
70