Talking to an Arduino from PHP
I was able to talk to my Arduino without using an Ethernet or a wireless shield.
Best part is that I only have 4 lines in my PHP script :)
Things you need to have :
Arduino board with a USB Cable
Breadboard
1 LED
Few jumper wires
220 OHM resistor
Additionally Arduino IDE, PHP, Apache2 installed Linux box :)
1. Connect Arduinos GND pin to breadboards ground line.
2. Connect Digital pin 13 to breadboards + line.
3. Connect LEDs Anode(long leg) with the breadboards + line using the 200 OHM resistor.
4. Connect LEDs cathode(short leg) with breadboards - line directly using a jumper cable.
You are done with the circuit prototype, Now connect the Arduino board to your PC.
Open Arduino IDE, click on tools> Serial port. You can see the device connected to a port similar to "/dev/ttyACM0".
Lets write our PHP snippet,
<?php
$comPort = "/dev/ttyACM0"; /*Update to the correct port */
$fp =fopen($comPort, "w");
fwrite($fp, "switch"); /* We are going to write "switch" */
fclose($fp);
?>That is it, host this snippet switch_uno.php within /var/www/php-arduino directory. lets write our Arduino sketch.
String val;
void setup()
{
Serial.begin(9600);
pinMode(13, OUTPUT);
}
void loop()
{
while (Serial.available()){
delay(10);
char c = Serial.read();
if (c == ,){
break;
}
val+= c;
}
if (val == "switch") {
if(digitalRead(13) == LOW){
digitalWrite(13, HIGH);
delay(100);
Serial.println(1);
}else if(digitalRead(13) == HIGH){
digitalWrite(13, LOW);
delay(100);
Serial.println(0);
}
val="";
}
}
Upload above sketch to your Arduino and open the serial monitor window within the Arduino IDE.
In order to execute our PHP snippet,
Lets open a terminal window and change directory to the /var/www/php-arduino directory.
run sudo php switch_uno.php your LED will be on :) If you run the same command again LED will be off.
You can do the same by using PHP serial class also.
download file now
