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Topic: input to variable from html on Webduino (Read 1 time) previous topic - next topic

eivis87

Hi,

I am trying to set the value in a variable from a text box or a dropdown on a html page hosted on the Arduino. This proved to be dificult. I have googeld around for hours, but can`t figure it out.

The goal with the code is to regulate the airflow and humidity in my cellar with some fans, and be able to adjust the setpoints for when the fans go ON/OFF

The web page is up and running and I have been abel to display the values from a temp/hum sensor on the web page. So long so good. But getting the variables the other way was not so easy.

I have used the Webduino example code. (I left out the temp/hum sensor in the code below because it got to messy) ;/

My hope is that some of you can give me an example.



Code: [Select]
/* Web_Demo.pde -- sample code for Webduino server library */

/*
* To use this demo,  enter one of the following USLs into your browser.
* Replace "host" with the IP address assigned to the Arduino.
*
* http://host/
* http://host/json
*
* This URL brings up a display of the values READ on digital pins 0-9
* and analog pins 0-5.  This is done with a call to defaultCmd.
*
*
* http://host/form
*
* This URL also brings up a display of the values READ on digital pins 0-9
* and analog pins 0-5.  But it's done as a form,  by the "formCmd" function,
* and the digital pins are shown as radio buttons you can change.
* When you click the "Submit" button,  it does a POST that sets the
* digital pins,  re-reads them,  and re-displays the form.
*
*/

#include "SPI.h"
#include "Ethernet.h"
#include "WebServer.h"

// no-cost stream operator as described at
// http://sundial.org/arduino/?page_id=119
template<class T>
inline Print &operator <<(Print &obj, T arg)
{ obj.print(arg); return obj; }


// CHANGE THIS TO YOUR OWN UNIQUE VALUE
static uint8_t mac[] = { 0xDE, 0xAD, 0xBE, 0xEF, 0xFE, 0xED };

// CHANGE THIS TO MATCH YOUR HOST NETWORK
static uint8_t ip[] = { 192, 168, 1, 210 };

#define PREFIX ""

WebServer webserver(PREFIX, 80);

// commands are functions that get called by the webserver framework
// they can read any posted data from client, and they output to server

void jsonCmd(WebServer &server, WebServer::ConnectionType type, char *url_tail, bool tail_complete)
{
  if (type == WebServer::POST)
  {
    server.httpFail();
    return;
  }

  //server.httpSuccess(false, "application/json");
  server.httpSuccess("application/json");
 
  if (type == WebServer::HEAD)
    return;

  int i;   
  server << "{ ";
  for (i = 0; i <= 9; ++i)
  {
    // ignore the pins we use to talk to the Ethernet chip
    int val = digitalRead(i);
    server << "\"d" << i << "\": " << val << ", ";
  }

  for (i = 0; i <= 5; ++i)
  {
    int val = analogRead(i);
    server << "\"a" << i << "\": " << val;
    if (i != 5)
      server << ", ";
  }
 
  server << " }";
}

void outputPins(WebServer &server, WebServer::ConnectionType type, bool addControls = false)
{
  P(htmlHead) =
    "<html>"
    "<head>"
    "<title>Arduino Web Server</title>"
    "<style type=\"text/css\">"
    "BODY { font-family: sans-serif }"
    "H1 { font-size: 14pt; text-decoration: underline }"
    "P  { font-size: 10pt; }"
    "</style>"
    "</head>"
    "<body>";

  int i;
  server.httpSuccess();
  server.printP(htmlHead);

  if (addControls)
    server << "<form action='" PREFIX "/form' method='post'>";

  server << "<h1>Digital Pins</h1><p>";

  for (i = 0; i <= 9; ++i)
  {
    // ignore the pins we use to talk to the Ethernet chip
    int val = digitalRead(i);
    server << "Digital " << i << ": ";
    if (addControls)
    {
      char pinName[4];
      pinName[0] = 'd';
      itoa(i, pinName + 1, 10);
      server.radioButton(pinName, "1", "On", val);
      server << " ";
      server.radioButton(pinName, "0", "Off", !val);
    }
    else
      server << (val ? "HIGH" : "LOW");

    server << "<br/>";
  }

  server << "</p><h1>Analog Pins</h1><p>";
  for (i = 0; i <= 5; ++i)
  {
    int val = analogRead(i);
    server << "Analog " << i << ": " << val << "<br/>";
  }

  server << "</p>";

  if (addControls)
    server << "<input type='submit' value='Submit'/></form>";

  server << "</body></html>";
}

void formCmd(WebServer &server, WebServer::ConnectionType type, char *url_tail, bool tail_complete)
{
  if (type == WebServer::POST)
  {
    bool repeat;
    char name[16], value[16];
    do
    {
      repeat = server.readPOSTparam(name, 16, value, 16);
      if (name[0] == 'd')
      {
        int pin = strtoul(name + 1, NULL, 10);
        int val = strtoul(value, NULL, 10);
        digitalWrite(pin, val);
      }
    } while (repeat);

    server.httpSeeOther(PREFIX "/form");
  }
  else
    outputPins(server, type, true);
}

void defaultCmd(WebServer &server, WebServer::ConnectionType type, char *url_tail, bool tail_complete)
{
  outputPins(server, type, false); 
}

void setup()
{
  // set pins 0-8 for digital input
  for (int i = 0; i <= 9; ++i)
    pinMode(i, INPUT);
  pinMode(9, OUTPUT);

  Ethernet.begin(mac, ip);
  webserver.begin();

  webserver.setDefaultCommand(&defaultCmd);
  webserver.addCommand("json", &jsonCmd);
  webserver.addCommand("form", &formCmd);
}

void loop()
{
  // process incoming connections one at a time forever
  webserver.processConnection();

  // if you wanted to do other work based on a connecton, it would go here
}




PaulS

You should not be using pins 0 or 1, either. They are the hardware serial port pins. What you should be doing is using the Serial instance to debug your program.

Clicking any of the buttons on the form seems to post something back to the Arduino. The jsonCmd() function seems to think that a POST reply is an error.

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