从Arduino返回PHP串行端口数据

Question

我想知道是否有一种方法可以通过PHP来完成对串行端口的读取——有效：——

在练习Arduino技能时，我设计了一个简单的LED开关示意图。它通过在串行监视器中输入on或off来工作。

下一步，我把一个网页放在一起，作为一个GUI界面，点击一个链接并执行上面的开关功能。这个基于网络的GUI通过PHP工作。我使用PHP串行类与Arduino使用的串行端口进行交互。

问题是我需要找到一种从串口获取反馈的方法。使用Arduino IDE串行监视器，我可以看到响应于每个串行输入的打印消息，我需要在PHP代码中检索相同的反馈。

PHP串行类提供了readPort（）函数，但我不返回数据。

更新[2]：

阿杜伊诺：

const int greenPin = 2;
const int bluePin = 3;
const int redPin = 4;

int currentPin = 0; //current pin to be faded
int brightness = 0; //current brightness level

void setup(){
  Serial.begin(9600);

  pinMode(greenPin, OUTPUT);
  pinMode(bluePin, OUTPUT);
  pinMode(redPin, OUTPUT);
}

void loop(){
  //if there's any serial data in the buffer, read a byte
  if( Serial.available() > 0 ){
    int inByte = Serial.read();

      //respond only to the values 'r', 'g', 'b', or '0' through '9'
      if(inByte == 'r')
        currentPin = redPin;

      if(inByte == 'g')
        currentPin = greenPin;

      if(inByte == 'b')
        currentPin = bluePin;

      if(inByte >= '0' && inByte <= '9'){
        //map the incoming byte value to the range of the analogRead() command
        brightness = map(inByte, '0', '9', 0, 255);
        //set the current pin to the current brightness:
        analogWrite(currentPin, brightness);
      }

      Serial.print("Current Pin : ");
      Serial.println(currentPin);

      Serial.print("Brightness : ");
      Serial.println(brightness);

  }//close serial check

}

PHP/HTML：

<?php
    require("php_serial.class.php");
// include("php_serial.class.php");

    // Let's start the class
    $serial = new phpSerial();

    // First we must specify the device. This works on both Linux and Windows (if
    // your Linux serial device is /dev/ttyS0 for COM1, etc.)
    $serial->deviceSet("/dev/ttyACM0");

    // Set for 9600-8-N-1 (no flow control)
    $serial->confBaudRate(9600); //Baud rate: 9600
    $serial->confParity("none");  //Parity (this is the "N" in "8-N-1")
    $serial->confCharacterLength(8); //Character length     (this is the "8" in "8-N-1")
    $serial->confStopBits(1);  //Stop bits (this is the "1" in "8-N-1")
    $serial->confFlowControl("none");

    // Then we need to open it
    $serial->deviceOpen();

    // Read data
    $read = $serial->readPort();
print "<pre>";
print_r($read);
print "</pre>";

    // Print out the data
    echo $read;
        // print exec("echo 'r9g9b9' > /dev/ttyACM0");
    print "RESPONSE(1): {$read}<br><br>";

    // If you want to change the configuration, the device must be closed.
    $serial->deviceClose();
?>

<?php
    if( isset($_REQUEST['LED']) )
        response();
?>

<form action='index.php' method='POST'>
    <select id='led' name='LED'>
        <option id='nil'>-</option>
        <option id='red'>RED</option>
        <option id='green'>GREEN</option>
        <option id='blue'>BLUE</option>
        <option id='all'>ALL</option>
    </select>
    <input type='submit' value='SET'>
</form>

<?php
    print "Hi, Earthlings!";

    function response(){
        $CMDString = "";
        $execute   = false;

        if( isset($_REQUEST['LED']) ){
                switch ($_REQUEST['LED']) {
                    case 'RED':
                        $CMDString = 'r9';
                        $execute = true;

        exec("echo 'r9g0b0' > /dev/ttyACM0");

                print "<br>FOUND: {$_REQUEST['LED']}";
                        break;
                    case 'GREEN':
                        $CMDString = 'g9';
                        $execute = true;
                print "<br>FOUND: {$_REQUEST['LED']}";
                        break;
                    case 'BLUE':
                        $CMDString = 'b9';
                        $execute = true;
                print "<br>FOUND: {$_REQUEST['LED']}";
                        break;
                    case 'ALL':
                        $CMDString = 'r9g9b9';
                        $execute = true;
                print "<br>FOUND: {$_REQUEST['LED']}";
                        break;
                    default:
                        print exec("echo 'r0g0b0' > /dev/ttyACM0");
                        $execute = false;
                        break;
                }

                if($execute){
                    print exec("echo '{$CMDString}' > /dev/ttyACM0");
                    print "<br><br>executing: {$CMDString}";
                }
        }
    }
?>

Answer 1

当串行端口上没有数据时，您可能正在尝试读取。您需要实现JavaScript代码来调用可以定期读取的PHP代码。

当你有了数据，你应该处理它。

readPort（）对我来说效果很好。如果波特率、奇偶校验等调整正确，那么读取串行端口应该不会有任何问题。

下面是使用Arduino库的示例。一段时间前，它对我起了作用：

<?php
    include "php_serial.class.php";

    // Let's start the class
    $serial = new phpSerial();

    // First we must specify the device. This works on both Linux and Windows (if
    // your Linux serial device is /dev/ttyS0 for COM1, etc.)
    $serial->deviceSet("/dev/ttyUSB0");

    // Set for 9600-8-N-1 (no flow control)
    $serial->confBaudRate(9600); //Baud rate: 9600
    $serial->confParity("none");  //Parity (this is the "N" in "8-N-1")
    $serial->confCharacterLength(8); //Character length     (this is the "8" in "8-N-1")
    $serial->confStopBits(1);  //Stop bits (this is the "1" in "8-N-1")
    $serial->confFlowControl("none");

    // Then we need to open it
    $serial->deviceOpen();

    // Read data
    $read = $serial->readPort();

    // Print out the data
    echo $read;

    // If you want to change the configuration, the device must be closed.
    $serial->deviceClose();
?>

Answer 2

/dev/ttyUSB0与用户root一起运行，如果您正在使用apache，请尝试将chown/dev/ttyUSB0连接到apache，或者用户已登录。

$ sudo chown apache2:apache2 /dev/ttyACM0
OR
$ sudo chown yourusername:yourusername /dev/ttyACM0

然后再试一次，或者尝试从ubuntu注销并以root用户身份登录。

Answer 3

我猜你在linux上工作。

首先设置您的串行端口：

stty -F /dev/ttyACM0 cs8 9600 ignbrk -brkint -imaxbel -opost -onlcr -isig -icanon -iexten -echo -echoe -echok -echoctl -echoke noflsh -ixon -crtscts

然后你可以使用好的老式fread/fwrite

$fp =fopen("/dev/ttyACM0", "w+");
if( !$fp) {
        echo "Error";die();
}

fwrite($fp, $_SERVER['argv'][1] . 0x00);
echo fread($fp, 10);

fclose($fp);

你只需要记住一件事。Arduino将在每个连接上重新启动。如果你不知道这会让你困惑。例如，如果你连接（fopen）并立即发送数据，Arduino会错过它，因为它正在启动（需要一两秒钟）。尝试睡眠，给它一些时间。如果你想禁用重启，使用10uF电容器从GRD到RST。

祝你好运

注：您可以使用“屏幕”进行故障排除

screen /dev/ttyACM0 9600

关于使用Arduino设置PHP的帖子http://systemsarchitect.net/connecting-php-with-arduino-via-serial-port-on-linux/还有一个http://systemsarchitect.net/arduino-and-php-serial-communication-with-a-protocol/.