how to read data from serial port in php code example
Example 1: how to read data from serial port in php
For Windows the Example 1 looks same this one:
<?php
exec('mode com1: baud=9600 data=8 stop=1 parity=n xon=on');
// execute 'help mode' in command line of Windows for help
$fd = dio_open('com1:', O_RDWR);
while (1) {
$data = dio_read($fd, 256);
if ($data) {
echo $data;
}
}
?>
Example 2: php read serial port
<?php
class Scanner {
protected $port; // port path, e.g. /dev/pts/5
protected $fd; // numeric file descriptor
protected $base; // EventBase
protected $dio; // dio resource
protected $e_open; // Event
protected $e_read; // Event
public function __construct ($port) {
$this->port = $port;
$this->base = new EventBase();
}
public function __destruct() {
$this->base->exit();
if ($this->e_open)
$this->e_open->free();
if ($this->e_read)
$this->e_read->free();
if ($this->dio)
dio_close($this->dio);
}
public function run() {
$stream = fopen($this->port, 'rb');
stream_set_blocking($stream, false);
$this->fd = EventUtil::getSocketFd($stream);
if ($this->fd < 0) {
fprintf(STDERR, "Failed attach to port, events: %d\n", $events);
return;
}
$this->e_open = new Event($this->base, $this->fd, Event::WRITE, [$this, '_onOpen']);
$this->e_open->add();
$this->base->dispatch();
fclose($stream);
}
public function _onOpen($fd, $events) {
$this->e_open->del();
$this->dio = dio_fdopen($this->fd);
// Call other dio functions here, e.g.
dio_tcsetattr($this->dio, [
'baud' => 9600,
'bits' => 8,
'stop' => 1,
'parity' => 0
]);
$this->e_read = new Event($this->base, $this->fd, Event::READ | Event::PERSIST,
[$this, '_onRead']);
$this->e_read->add();
}
public function _onRead($fd, $events) {
while ($data = dio_read($this->dio, 1)) {
var_dump($data);
}
}
}
// Change the port argument
$scanner = new Scanner('/dev/pts/5');
$scanner->run();