I have been creating a small home automation system, I can turn my lights on via a webpage. I also have a LDR working and I would like to send the value of the LDR back to the webpage.
I know I can post a HTTP request in and turn the lights on. I have no idea how to alter the code below to handle the lights and return a request for the value of the LDR, if anyone can point me in the right direction that would be a massive help.
Thanks
EthernetClient client = server.available(); // try to get client
if (client) { // got client?
boolean currentLineIsBlank = true;
while (client.connected()) {
if (client.available()) { // client data available to read
char c = client.read(); // read 1 byte (character) from client
HTTP_req += c; // save the HTTP request 1 char at a time
// last line of client request is blank and ends with \n
// respond to client only after last line received
if (c == '\n' && currentLineIsBlank) {
// send a standard http response header
client.println("HTTP/1.1 200 OK");
client.println("Content-Type: text/html");
client.println("Connection: close");
client.println();
// send web page
client.println("<!DOCTYPE html>");
client.println("<html>");
client.println("<head>");
client.println("<title>Arduino LED Control</title>");
client.println("</head>");
client.println("<body>");
client.println("<h1>LED</h1>");
client.println("<p>Click to switch LED on and off.</p>");
client.println("<form method=\"get\">");
ProcessCheckbox(client);
client.println("</form>");
client.println("</body>");
client.println("</html>");
Serial.print(HTTP_req);
HTTP_req = ""; // finished with request, empty string
break;
}
// every line of text received from the client ends with \r\n
if (c == '\n') {
// last character on line of received text
// starting new line with next character read
currentLineIsBlank = true;
}
else if (c != '\r') {
// a text character was received from client
currentLineIsBlank = false;
}
} // end if (client.available())
} // end while (client.connected())
delay(1); // give the web browser time to receive the data
client.stop(); // close the connection
} // end if (client)
// switch LED and send back HTML for LED checkbox
void ProcessCheckbox(EthernetClient cl)
{
if (HTTP_req.indexOf("LED2=2") > -1) { // see if checkbox was clicked
// the checkbox was clicked, toggle the LED
if (LED_status) {
LED_status = 0;
}
else {
LED_status = 1;
}
}
if (LED_status) { // switch LED on
digitalWrite(12, HIGH);
// checkbox is checked
cl.println("<input type=\"checkbox\" name=\"LED2\" value=\"2\" \
onclick=\"submit();\" checked>LED2");
}
else { // switch LED off
digitalWrite(12, LOW);
// checkbox is unchecked
cl.println("<input type=\"checkbox\" name=\"LED2\" value=\"2\" \
onclick=\"submit();\">LED2");
}
}
I have no idea how to alter the code below to handle the lights
Isn't that code already handling the lights?
and return a request for the value of the LDR
You can't "return a request". You can return the value of the LDR.
That code has the Arduino acting as a server. It can supply responses to GET requests. Some of the responses can involve toggling pins as well as returning HTML.
// zoomkat's meta refresh data frame test page 5/25/13
// use http://192.168.1.102:84 in your brouser for main page
// http://192.168.1.102:84/data static data page
// http://192.168.1.102:84/datastart meta refresh data page
// for use with W5100 based ethernet shields
// set the refresh rate to 0 for fastest update
// use STOP for single data updates
#include <SPI.h>
#include <Ethernet.h>
const int analogInPin0 = A0;
const int analogInPin1 = A1;
const int analogInPin2 = A2;
const int analogInPin3 = A3;
const int analogInPin4 = A4;
const int analogInPin5 = A5;
byte mac[] = { 0xDE, 0xAD, 0xBE, 0xEF, 0xFE, 0xED }; //physical mac address
byte ip[] = { 192, 168, 1, 102 }; // arduino ip in lan
byte gateway[] = { 192, 168, 1, 1 }; // internet access via router
byte subnet[] = { 255, 255, 255, 0 }; //subnet mask
EthernetServer server(84); //server port
unsigned long int x=0; //set refresh counter to 0
String readString;
//////////////////////
void setup(){
Serial.begin(9600);
// disable SD SPI if memory card in the uSD slot
pinMode(4,OUTPUT);
digitalWrite(4,HIGH);
Ethernet.begin(mac, ip, gateway, gateway, subnet);
server.begin();
Serial.println("meta refresh data frame test 5/25/13"); // so I can keep track of what is loaded
}
void loop(){
EthernetClient client = server.available();
if (client) {
while (client.connected()) {
if (client.available()) {
char c = client.read();
if (readString.length() < 100) {
readString += c;
}
//check if HTTP request has ended
if (c == '\n') {
//check get atring received
Serial.println(readString);
//output HTML data header
client.println("HTTP/1.1 200 OK");
client.println("Content-Type: text/html");
client.println();
//generate data page
if(readString.indexOf("data") >0) { //checks for "data" page
x=x+1; //page upload counter
client.print("<HTML><HEAD>");
//meta-refresh page every 1 seconds if "datastart" page
if(readString.indexOf("datastart") >0) client.print("<meta http-equiv='refresh' content='1'>");
//meta-refresh 0 for fast data
if(readString.indexOf("datafast") >0) client.print("<meta http-equiv='refresh' content='0'>");
client.print("<title>Zoomkat's meta-refresh test</title></head><BODY>
");
client.print("page refresh number: ");
client.print(x); //current refresh count
client.print("
");
//output the value of each analog input pin
client.print("analog input0 is: ");
client.print(analogRead(analogInPin0));
client.print("
analog input1 is: ");
client.print(analogRead(analogInPin1));
client.print("
analog input2 is: ");
client.print(analogRead(analogInPin2));
client.print("
analog input3 is: ");
client.print(analogRead(analogInPin3));
client.print("
analog input4 is: ");
client.print(analogRead(analogInPin4));
client.print("
analog input5 is: ");
client.print(analogRead(analogInPin5));
client.println("
</BODY></HTML>");
}
//generate main page with iframe
else
{
client.print("<HTML><HEAD><TITLE>Zoomkat's frame refresh test</TITLE></HEAD>");
client.print("Zoomkat's Arduino frame meta refresh test 5/25/13");
client.print("
Arduino analog input data frame:
");
client.print(" <a href='http://192.168.1.102:84/datastart' target='DataBox' title=''yy''>META-REFRESH</a>");
client.print(" <a href='http://192.168.1.102:84/data' target='DataBox' title=''xx''>SINGLE-STOP</a>");
client.print(" <a href='http://192.168.1.102:84/datafast' target='DataBox' title=''zz''>FAST-DATA</a>
");
client.print("<iframe src='http://192.168.1.102:84/data' width='350' height='250' name='DataBox'>");
client.print("</iframe>
</HTML>");
}
delay(1);
//stopping client
client.stop();
//clearing string for next read
readString="";
}
}
}
}
}
will look at that, however what I am really confused about is how to check if the request coming is asking for the status of something ie a variable value, or it's a request to toggle a pin high or low or light on or off.
will look at that, however what I am really confused about is how to check if the request coming is asking for the status of something ie a variable value, or it's a request to toggle a pin high or low or light on or off.
Are you even printing the GET request? If not (and you aren't in your code), why the hell not?
Hi
I lifted the code from a tutorial for turning a led on/off via web page. Sorry for being vague but not sure what printing get means, sorry figuring this as I go.
char c = client.read(); // read 1 byte (character) from client
HTTP_req += c; // save the HTTP request 1 char at a time
Here:
if (c == '\n' && currentLineIsBlank) {
// send a standard http response header
You are assuming that you know what the client wants (you do not), and send the same response no matter what the client asked for.
Then, later on:
if (HTTP_req.indexOf("LED2=2") > -1) { // see if checkbox was clicked
You see if the client said that LED2 should have the value of 2.
After you think the client request is complete, print what the client asked:
if (c == '\n' && currentLineIsBlank)
{ // Down here where it belongs
Serial.print("Client request: [");
Serial.print(HTTP_req);
Serial.println("]");
// send a standard http response header
You could then make a more intelligent response based on what the client is actually asking for.
Sending the main page when the client requested the favicon doesn't make sense.