Hi there, with this sample you should be able to turn on/off a light, i'm posting this beacuse an user of this forum asked me how to make it and i thought it was nice sharing this with all the people.
#include <SPI.h>
#include <Ethernet.h>
#define action_none -1
#define action_out_all 0
#define action_on_light 1
#define action_off_light 2
byte mac[] = { 0xDE, 0xAD, 0xBE, 0xEF, 0xFE, 0xBE }; //physical mac address
byte ip[] = { 192, 168, 1, 16 }; // ip address
byte gateway[] = { 192, 168, 1, 1 }; // internet access via router
byte subnet[] = { 255, 255, 255, 0 }; //subnet mask
Server server(80); //server port
String readString = String(30); //string for fetching data from address
// arduino out
int pinOutPlight = 4;
// incoming GET command
String r_pinOnLight = "GET /?out=4&status=1";
String r_pinOffLight = "GET /?out=4&status=0";
String r_out_all = "GET /?out=all";
// current action
int current_action;
void setup(){
//start Ethernet
Ethernet.begin(mac, ip, gateway, subnet);
delay(1000);
pinMode(pinOutPlight, OUTPUT);
digitalWrite(pinOutPlight, LOW);
//enable serial datada print
Serial.begin(9600);
current_action = -1;
}
void loop(){
current_action = -1;
// Create a client connection
Client client = server.available();
if (client) {
while (client.connected()) {
if (client.available()) {
char c = client.read();
//read char by char HTTP request
if (readString.length() < 30)
{
//store characters to string
readString = readString + c;
}
//output chars to serial port
//Serial.print(c);
//if HTTP request has ended
if (c == '\n') {
Serial.print(readString);
// ****************************************************
if(readString.startsWith(r_pinOnLight))
{
Serial.print("\n ON UP \n");
current_action = action_on_light;
}
else if(readString.startsWith(r_pinOffLight))
{
Serial.print("\n OFF UP \n");
current_action = action_off_light;
}
else if(readString.startsWith(r_out_all))
{
Serial.print("\n ALL\n");
current_action = action_out_all;
}
else
{
Serial.print("\n None \n");
current_action = action_none;
}
// ****************************************************
// now output HTML data starting with standart header
client.println("HTTP/1.1 200 OK");
client.println("Content-Type: text/html");
client.println();
char buf[12];
switch(current_action)
{
case action_out_all:
client.print("{\"ip\" : \"192.168.10.16\", \"devices\" : [{ \"type\" : \"light\", \"name\" : \"your name\", \"out\" : \"");
client.print(pinOutPlight);
client.print("\"}");
client.print("]}");
break;
case action_on_light:
digitalWrite(pinOutPlight, HIGH);
client.print("{\"status\" : \"1\" , \"out\" : \"");
client.print(pinOutPlight);
client.print("\"}");
break;
case action_off_light:
digitalWrite(pinOutPlight, LOW);
client.print("{\"status\" : \"0\" , \"out\" : \"");
client.print(pinOutPlight);
client.print("\"}");
break;
default:
current_action = action_none;
}
// ****************************************************
//clearing string for next read
readString="";
//stopping client
client.stop();
}
}
}
}
}
you have to change your ip in the sketch. It's just a demo, any improvement are welcome.