Ok, I've been wrestling with trying to get ethernet stuff to work - local network only ... Arduino --> Ethernet shield --> router --> local PC. I used the IDE WebServer sketch, with tiny modifications to eliminate auto-refreshing, plus indicate to the SerialMonitor when the analog readings are sent,
/*
Web Server
A simple web server that shows the value of the analog input pins.
using an Arduino Wiznet Ethernet shield.
Circuit:
* Ethernet shield attached to pins 10, 11, 12, 13
* Analog inputs attached to pins A0 through A5 (optional)
created 18 Dec 2009
by David A. Mellis
modified 9 Apr 2012
by Tom Igoe */
#include <SPI.h>
#include <Ethernet.h>
// Enter a MAC address and IP address for your controller below.
// The IP address will be dependent on your local network:
byte mac[] = { 0xDE, 0xAD, 0xBE, 0xEF, 0xFE, 0xED };
IPAddress ip(192,168,1,177);
// Initialize the Ethernet server library
// with the IP address and port you want to use
// (port 80 is default for HTTP):
EthernetServer server(80);
void setup()
{
// Open serial communications and wait for port to open:
Serial.begin(57600);
// while (!Serial.available() ) {
// ; // wait for serial port to connect. Needed for Leonardo only
// }
// start the Ethernet connection and the server:
Ethernet.begin(mac, ip);
server.begin();
Serial.print("server is at ");
Serial.println(Ethernet.localIP());
}
void loop()
{
// listen for incoming clients
EthernetClient client = server.available();
if (client) {
Serial.println("new client");
// an http request ends with a blank line
boolean currentLineIsBlank = true;
while (client.connected()) {
if (client.available()) {
char c = client.read();
Serial.write(c);
// if you've gotten to the end of the line (received a newline
// character) and the line is blank, the http request has ended,
// so you can send a reply
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"); // the connection will be closed after completion of the response
// client.println("Refresh: 5"); // refresh the page automatically every 5 sec
client.println();
client.println("<!DOCTYPE HTML>");
client.println("<html>");
// NEW (08/17/13)
Serial.println("-analog display");
//output the value of each analog input pin
for (int analogChannel = 0; analogChannel < 6; analogChannel++) {
int sensorReading = analogRead(analogChannel);
client.print("analog input ");
client.print(analogChannel);
client.print(" is ");
client.print(sensorReading);
client.println("
");
}
client.println("</html>");
break;
}
if (c == '\n') {
// you're starting a new line
currentLineIsBlank = true;
}
else if (c != '\r') {
// you've gotten a character on the current line
currentLineIsBlank = false;
}
}
}
// give the web browser time to receive the data
delay(1);
// close the connection:
client.stop();
Serial.println("client disonnected");
}
}
I had noticed in my other programs the enormous amount of junk sent over the link when a page update is requested, see below.
My question is - from the monitor dump it looks like the ... if (c == '\n' && currentLineIsBlank) { ... part of the loop is executed "4" times whenever a page update is performed. IE, notice that "-analog display" prints out multiple times for each refresh request. There are 2 refreshes shown below, demarcated with the "****************' line.
What is going on here? Why so much garbage? Why repeat 4 times?
new client
GET / HTTP/1.1
Host: 192.168.1.177
Connection: keep-alive
Cache-Control: max-age=0
Accept: text/html,application/xhtml+xml,application/xml;q=0.9,/;q=0.8
User-Agent: Mozilla/5.0 (Linux; Android 4.2.1) AppleWebKit/537.31 (KHTML, like Gecko) Chrome/26.0.1410.58 Safari/537.31
DNT: 1
Accept-Encoding: gzip,deflate,sdch
Accept-Language: en-US,en;q=0.8
Accept-Charset: ISO-8859-1,utf-8;q=0.7,*;q=0.3-analog display
client disonnected
new client
GET /favicon.ico HTTP/1.1
Host: 192.168.1.177
Connection: keep-alive
Accept: /
DNT: 1
User-Agent: Mozilla/5.0 (Linux; Android 4.2.1) AppleWebKit/537.31 (KHTML, like Gecko) Chrome/26.0.1410.58 Safari/537.31
Accept-Encoding: gzip,deflate,sdch
Accept-Language: en-US,en;q=0.8
Accept-Charset: ISO-8859-1,utf-8;q=0.7,*;q=0.3-analog display
client disonnected
new client
GET /apple-touch-icon-precomposed.png HTTP/1.1
Host: 192.168.1.177
Connection: keep-alive
Accept: /
DNT: 1
User-Agent: Mozilla/5.0 (Linux; Android 4.2.1) AppleWebKit/537.31 (KHTML, like Gecko) Chrome/26.0.1410.58 Safari/537.31
Accept-Encoding: gzip,deflate,sdch
Accept-Language: en-US,en;q=0.8
Accept-Charset: ISO-8859-1,utf-8;q=0.7,*;q=0.3-analog display
client disonnected
new client
GET /apple-touch-icon.png HTTP/1.1
Host: 192.168.1.177
Connection: keep-alive
Accept: /
DNT: 1
User-Agent: Mozilla/5.0 (Linux; Android 4.2.1) AppleWebKit/537.31 (KHTML, like Gecko) Chrome/26.0.1410.58 Safari/537.31
Accept-Encoding: gzip,deflate,sdch
Accept-Language: en-US,en;q=0.8
Accept-Charset: ISO-8859-1,utf-8;q=0.7,*;q=0.3-analog display
client disonnected
new client
GET / HTTP/1.1
Host: 192.168.1.177
Connection: keep-alive
Cache-Control: max-age=0
Accept: text/html,application/xhtml+xml,application/xml;q=0.9,/;q=0.8
User-Agent: Mozilla/5.0 (Linux; Android 4.2.1) AppleWebKit/537.31 (KHTML, like Gecko) Chrome/26.0.1410.58 Safari/537.31
DNT: 1
Accept-Encoding: gzip,deflate,sdch
Accept-Language: en-US,en;q=0.8
Accept-Charset: ISO-8859-1,utf-8;q=0.7,*;q=0.3-analog display
client disonnected
new client
GET /favicon.ico HTTP/1.1
Host: 192.168.1.177
Connection: keep-alive
Accept: /
DNT: 1
User-Agent: Mozilla/5.0 (Linux; Android 4.2.1) AppleWebKit/537.31 (KHTML, like Gecko) Chrome/26.0.1410.58 Safari/537.31
Accept-Encoding: gzip,deflate,sdch
Accept-Language: en-US,en;q=0.8
Accept-Charset: ISO-8859-1,utf-8;q=0.7,*;q=0.3-analog display
client disonnected
new client
GET /apple-touch-icon-precomposed.png HTTP/1.1
Host: 192.168.1.177
Connection: keep-alive
Accept: /
DNT: 1
User-Agent: Mozilla/5.0 (Linux; Android 4.2.1) AppleWebKit/537.31 (KHTML, like Gecko) Chrome/26.0.1410.58 Safari/537.31
Accept-Encoding: gzip,deflate,sdch
Accept-Language: en-US,en;q=0.8
Accept-Charset: ISO-8859-1,utf-8;q=0.7,*;q=0.3-analog display
client disonnected
new client
GET /apple-touch-icon.png HTTP/1.1
Host: 192.168.1.177
Connection: keep-alive
Accept: /
DNT: 1
User-Agent: Mozilla/5.0 (Linux; Android 4.2.1) AppleWebKit/537.31 (KHTML, like Gecko) Chrome/26.0.1410.58 Safari/537.31
Accept-Encoding: gzip,deflate,sdch
Accept-Language: en-US,en;q=0.8
Accept-Charset: ISO-8859-1,utf-8;q=0.7,*;q=0.3-analog display
client disonnected
