从php到arduino的串行通信

Question

i want to pass a number from php to arduino. currently, i am able to communicate between php and arduino via serial port. however, when i try to pass a number(int) from php to arduino, the arduino can't identify it. then i try to pass an character(char) it is able to detect. i have tried multiple times and i don't know what is wrong with the code. below is my code.

PHP CODE

$X = $_POST['x'];
$Y = $_POST['y'];

$query = "INSERT INTO target_position (X,Y,Date) VALUES('$X','$Y',now())";
$insert = mysql_query($query);

$serial = new phpSerial();
$serial ->deviceSet("COM6");    //Port number
$serial ->confbaudRate(9600);
$serial ->confParity("none");
$serial ->confCharacterLength(8);
$serial ->confStopBits(1);
$serial ->confFlowControl("none");
$serial ->deviceOpen();
$serial ->sendMessage('1');
//$serial ->sendMessage('$Y');
//$jinhong =$serial ->readPort();
$serial ->deviceClose();

//echo $jinhong;

here is the arduino code

int led =13;
int test=0;

void setup()
{
  Serial.begin(9600);
  pinMode(led, OUTPUT);
}
void loop()
{
   while(Serial.available()==0);
   test=Serial.read();

   if(test=='1')
   {
      digitalWrite(led,HIGH);
      delay(500);
      digitalWrite(led,LOW);
      delay(500);
      digitalWrite(led,HIGH);
      delay(500);
      digitalWrite(led,LOW);
   }
}

Anyone can tell me what is wrong? The led doesn't light up at when i send 1. however when i send 'A', the led is up.

Answer 1

as a quick check can you do this to make sure you're dealing with the right data types (i.e. if you're sending a string or an int and checking for either or.

void loop(){

    if (Serial.available()) {

        char ch = Serial.read();

        if(ch == '1'){

            // your led logic here

        }

    }

}

ok now to try to cut the long story short. i tested this stuff myself and the following code is functional. What I noticed was that the serial monitor in the arduino IDE needed to be open for this to work as expected. When it wasn't open the correct data wasnt being read nor was the PHP script exiting. I'm thinking the problem here is that your arduino environment is trying to communicate to the device over the same serial port that your PHP is trying to talk over too. You'll probably have to investigate how to disable that communication while youre trying to use your PHP script(s)

<?php
include 'PhpSerial.php';

$serial = new PhpSerial;

$serial->deviceSet("/dev/tty.usbserial-A9IL9BF7");

$serial->confBaudRate(9600);
$serial->confParity("none");
$serial->confCharacterLength(8);
$serial->confStopBits(1);
$serial->confFlowControl("none");

$serial->deviceOpen();

$read = $serial->readPort();

$serial ->sendMessage('1');

$serial ->deviceClose();

?>


int led = 13;

void setup() {
    pinMode(led, OUTPUT);
    Serial.begin(9600);     
}

void loop() {

    if (Serial.available() == 1) {

        char ch = Serial.read();

        if (ch == '1'){

            digitalWrite(led,HIGH);
            delay(500);
            digitalWrite(led,LOW);
            delay(500);
            digitalWrite(led,HIGH);
            delay(500);
            digitalWrite(led,LOW);

        }

    }
}