HTTP Server serving a simple webpage which enables to remotely turn a digital output on/off. Compile, download, run and type 'IP_address/secret/' (don't forget the last '/') into your web browser and hit ENTER.

Dependencies:   UIPEthernet

Turn LED1, or other digital output, on/off using a web browser.

In this example we create a HTTP server that will serve a simple Web page to remotely turn LED1, or other digital output on the mbed board, on/off by using a web browser. An inexpensive ENC28J60 Ethernet module is used to assure connection between the mbed board and the Ethernet network (Internet). The ENC28J60 Ethernet module is driven by the UIPEthernet library.

Needed parts:

  • mbed board
  • ENC28J60 Ethernet module
  • Wires
  • Web browser (Internet Explorer, Safari, Firefox, Chrome ...) running on Windows, Mac, Linux, iPhone or Android device.
/media/uploads/hudakz/webswitch_enc.jpg/media/uploads/hudakz/webswitch_mobile01.jpg

Notice that DHCP is turned on by default. If you prefer to use static IP address then uncomment line 234

The IP address assigned to the WebSwitch server along with an instruction how to use it is printed in the connected PC's serial terminal window during program start up.

Warning

Please notice that the 3.3V power supply chip (RT8183-B) installed on an STM32F103C8T6 board is not rated to power also the ENC28J60 board.


The project was inspired by the Tuxgraphics Web Switch. Thank you Guido!

NOTE:

Revision:
7:f5e11393836d
Parent:
6:b38a3b476a45
Child:
8:3bd85b731cca
--- a/main.cpp	Sun Aug 28 11:47:29 2016 +0000
+++ b/main.cpp	Mon May 01 20:06:24 2017 +0000
@@ -1,21 +1,22 @@
-/* 
+/*
  * In this project LED1 on the mbed board is switched on/off using a web browser.
  * However, you can easily modify the project to remotely switch on/off any external device.
  * The HTTP server is built from an mbed board and an ENC28J60 board.
  * ENC28J60 is driven by the UIPEthernet library <https://github.com/ntruchsess/arduino_uip>.
  * The example is based on the Tuxgraphics Web Switch <http://www.tuxgraphics.org/>.
  */
- 
-//#define TARGET_STM32F103C8T6  1     // uncomment this line when using STM32F103C8T6 boards!                                    
+
+//#define TARGET_STM32F103C8T6  1     // uncomment this line when using STM32F103C8T6 boards!
 
 #if defined(TARGET_STM32F103C8T6)
-    #define LED_PIN PC_13
-    const int OFF = 1;
-    const int ON  = 0;
+#include "stm32f103c8t6.h"
+#define LED_PIN PC_13
+const int OFF = 1;
+const int ON  = 0;
 #else
-    #define LED_PIN LED1
-    const int OFF = 0;
-    const int ON  = 1;
+#define LED_PIN LED1
+const int OFF = 0;
+const int ON  = 1;
 #endif
 
 #include "mbed.h"
@@ -42,7 +43,9 @@
    || defined(TARGET_NUCLEO_F401RE) || defined(TARGET_NUCLEO_F302R8) || defined(TARGET_NUCLEO_L053R8)  \
    || defined(TARGET_NUCLEO_F411RE) || defined(TARGET_NUCLEO_F334R8) || defined(TARGET_NUCLEO_F072RB)  \
    || defined(TARGET_NUCLEO_F091RC) || defined(TARGET_NUCLEO_F303RE) || defined(TARGET_NUCLEO_F070RB)
-UIPEthernetClass    UIPEthernet(D4, D5, D3, D2);            // mosi, miso, sck, cs
+//UIPEthernetClass    UIPEthernet(D4, D5, D3, D2);            // mosi, miso, sck, cs
+//UIPEthernetClass    UIPEthernet(D11, D12, D13, D10);            // mosi, miso, sck, cs
+UIPEthernetClass    UIPEthernet(PA_7, PA_6, PA_5, PB_6);            // mosi, miso, sck, cs
 
 // If your board/plaform is not present yet then uncomment
 // the following two lines and replace TARGET_YOUR_BOARD as appropriate.
@@ -65,7 +68,9 @@
 EthernetServer      myServer = EthernetServer(MY_PORT);
 
 // In this example we are turning on/off LED1.
-DigitalOut          sw(LED_PIN);            // Change LED_PIN to a pin of your choice.
+DigitalOut          sw(LED_PIN);        // Change LED_PIN to a pin of your choice.
+//DigitalOut          sw(D9);           // Change LED_PIN to a pin of your choice.
+float               roomTemp = 21.8;    // A temperature sensor output
 
 // However, make sure that it does not collide with any of the SPI pins
 // already used in the UIPEthernet(...) constructor above!
@@ -76,33 +81,33 @@
 string              httpHeader;     // HTTP header
 string              httpContent;    // HTTP content
 
-// analyse the url given
-// return values: -1 invalid password
-//                -2 no command given but password valid
-//                -3 just refresh page
-//                 0 switch off
-//                 1 switch on
-//
-//                The string passed to this function will look like this:
-//                GET /password HTTP/1.....
-//                GET /password/ HTTP/1.....
-//                GET /password/?sw=1 HTTP/1.....
-//                GET /password/?sw=0 HTTP/1.....
-int8_t analyseURL(string& str) {
-    if(str.substr(5, PASSWORD.size()) != PASSWORD)
+/**
+ * @brief   Analyses the received URL
+ * @note    The string passed to this function will look like this:
+ *          GET /password HTTP/1.....
+ *          GET /password/ HTTP/1.....
+ *          GET /password/?sw=1 HTTP/1.....
+ *          GET /password/?sw=0 HTTP/1.....
+ * @param   url URL string
+ * @retval -1 invalid password
+ *         -2 no command given but password valid
+ *         -3 just refresh page
+ *          0 switch off
+ *          1 switch on
+ */
+int8_t analyseURL(string& url) {
+    if(url.substr(5, PASSWORD.size()) != PASSWORD)
         return(-1);
 
     uint8_t pos = 5 + PASSWORD.size();
 
-    if(str.substr(pos, 1) == " ")
+    if(url.substr(pos, 1) == " ")
         return(-2);
 
-    if(str.substr(pos, 1) != "/")
+    if(url.substr(pos++, 1) != "/")
         return(-1);
 
-    pos++;
-
-    string  cmd(str.substr(pos, 5));
+    string  cmd(url.substr(pos, 5));
 
     if(cmd == "?sw=0")
         return(OFF);
@@ -119,7 +124,8 @@
  * @param
  * @retval
  */
-string& movedPermanently(uint8_t flag) {
+string& movedPermanently(uint8_t flag)
+{
     if(flag == 1)
         httpContent = "/" + PASSWORD + "/";
     else
@@ -137,20 +143,26 @@
  * @retval
  */
 string& showWebPage(uint8_t status) {
-    httpContent = "<h2>Web Switch</h2>\r\n";
+    char roomTempStr[5];
+
+    //roomTemp = ds1820.read();
+    sprintf(roomTempStr, "%3.1f", roomTemp);
+
+    httpContent = "<h2><a href=\".\" title=\"Click to refresh the page\">Smart Home</a></h2>"; 
+    httpContent += "<pre>Temperature:\t" + string(roomTempStr) + "&deg;C\r\n</pre>";
 
     if(status == ON) {
-        httpContent += "<pre>\r\n  <font color=#FF0000>ON </font>";
-        httpContent += " <a href=\"./?sw=0\">[Turn off]</a>\r\n";
+        httpContent += "<pre>\r\nHeating:\t<font color=#FF0000>On </font>";
+        httpContent += " <a href=\"./?sw=0\"><button>Turn off</button></a>\r\n";
     }
     else {
-        httpContent += "<pre>\r\n  <font color=#BBBBBB>OFF</font>";
-        httpContent += " <a href=\"./?sw=1\">[Turn on]</a>\r\n";
+        httpContent += "<pre>\r\nHeating:\t<font color=#999999>Off</font>";
+        httpContent += " <a href=\"./?sw=1\"><button>Turn on</button></a>\r\n";
     }
 
-//    httpContent += "  <a href=\".\">[refresh status]</a>\r\n";
     httpContent += "</pre>\r\n";
     httpContent += "<hr>\r\n";
+    httpContent += "<pre>2017 ARMmbed</pre>";
     return httpContent;
 }
 
@@ -160,7 +172,8 @@
  * @param
  * @retval
  */
-void sendHTTP(EthernetClient& client, string& header, string& content) {
+void sendHTTP(EthernetClient& client, string& header, string& content)
+{
     char    content_length[5] = { };
 
     header += "\r\nContent-Type: text/html\r\n";
@@ -181,7 +194,11 @@
  * @param
  * @retval
  */
-int main(void) {
+int main(void)
+{
+#if defined(TARGET_STM32F103C8T6)
+    confSysClock();     //Configure system clock (72MHz HSE clock, 48MHz USB clock)
+#endif
 #if defined(DHCP)
     pc.printf("Searching for DHCP server..\r\n");
     if(UIPEthernet.begin(MY_MAC) != 1) {
@@ -210,7 +227,7 @@
                 size = client.read(buf, size);
                 string  received((char*)buf);
                 free(buf);
-                
+
                 if(received.substr(0, 3) != "GET") {
                     httpHeader = HTTP_OK;
                     httpContent = "<h1>200 OK</h1>";