main.cpp

00001 // ESP8266 Static page WEB server to control Mbed
00002 
00003 #include "mbed.h"
00004 
00005 Serial pc(USBTX, USBRX);
00006 Serial esp(p28, p27); // tx, rx
00007 
00008 
00009 // Standard Mbed LED definitions
00010 DigitalOut  led1(LED1);
00011 DigitalOut  led2(LED2);
00012 DigitalOut  led3(LED3);
00013 DigitalOut  led4(LED4);
00014 
00015 // some test values to show on web page
00016 AnalogIn   Ain1(p18);
00017 AnalogIn   Ain2(p19);
00018 
00019 /*
00020 char ssid[32] = "hsd";     // enter WiFi router ssid inside the quotes
00021 char pwd [32] = "austin123"; // enter WiFi router password inside the quotes
00022 */
00023 float temperature, AdcIn, Ht;
00024 float R1=100000, R2=10000; // resistor values to give a 10:1 reduction of measured AnalogIn voltage
00025 char Vcc[10];
00026 char Temp[10];
00027 
00028 // things for sending/receiving data over serial
00029 volatile int tx_in=0;
00030 volatile int tx_out=0;
00031 volatile int rx_in=0;
00032 volatile int rx_out=0;
00033 const int buffer_size = 4095;
00034 char tx_buffer[buffer_size+1];
00035 char rx_buffer[buffer_size+1];
00036 void Tx_interrupt();
00037 void Rx_interrupt();
00038 void send_line();
00039 void read_line();
00040 
00041 int DataRX;
00042 int update;
00043 int count;
00044 char cmdbuff[1024];
00045 char replybuff[4096];
00046 char webdata[4096]; // This may need to be bigger depending on WEB browser used
00047 char webbuff[4096];     // Currently using 1986 characters, Increase this if more web page data added
00048 char timebuf[30];
00049 void SendCMD(),getreply(),ReadWebData(),startserver();
00050 void gettime(),setRTC(),gettemp(),getbattery();
00051 char rx_line[1024];
00052 int port        =80;  // set server port
00053 int SERVtimeout =5;    // set server timeout in seconds in case link breaks.
00054 struct tm t;
00055 // manual set RTC values
00056 int minute      =00;    // 0-59
00057 int hour        =12;    // 2-23
00058 int dayofmonth  =26;    // 1-31
00059 int month       =8;     // 1-12
00060 int year        =15;    // last 2 digits
00061 
00062 int main()
00063 {
00064     pc.baud(9600);
00065     esp.baud(9600);
00066     led1=1,led2=0,led3=0, led4=0;
00067     // Setup a serial interrupt function to receive data
00068     esp.attach(&Rx_interrupt, Serial::RxIrq);
00069     // Setup a serial interrupt function to transmit data
00070     esp.attach(&Tx_interrupt, Serial::TxIrq);
00071     if (time(NULL) < 1420070400) {
00072         setRTC();
00073     }
00074     startserver();
00075     DataRX=0;
00076     count=0;
00077     while(1) {
00078         if(DataRX==1) {
00079             ReadWebData();
00080             esp.attach(&Rx_interrupt, Serial::RxIrq);
00081         }
00082         if(update==1) // update time, hit count, and analog levels in the HUZZAH chip
00083         {
00084             // get new values
00085             gettime();
00086             gettemp();
00087             getbattery();
00088             count++;
00089             // send new values
00090             sprintf(cmdbuff, "count,time,analog1,analog2=%d,\"%s\",\"%s\",\"%s\"\r\n",count,timebuf,Temp,Vcc);
00091             SendCMD();
00092             getreply();
00093             update=0;   
00094         }
00095     }
00096 }
00097 
00098 // Reads and processes GET and POST web data
00099 void ReadWebData()
00100 {
00101     wait_ms(200);
00102     esp.attach(NULL,Serial::RxIrq);
00103     DataRX=0;
00104     memset(webdata, '\0', sizeof(webdata));
00105     strcpy(webdata, rx_buffer);
00106     memset(rx_buffer, '\0', sizeof(rx_buffer));
00107     rx_in = 0;
00108     rx_out = 0;
00109     // check web data for form information
00110     if( strstr(webdata, "check=led1v") != NULL ) {
00111         led1=!led1;
00112     }
00113     if( strstr(webdata, "check=led2v") != NULL ) {
00114         led2=!led2;
00115     }
00116     if( strstr(webdata, "check=led3v") != NULL ) {
00117         led3=!led3;
00118     }
00119     if( strstr(webdata, "check=led4v") != NULL ) {
00120         led4=!led4;
00121     }
00122     if( strstr(webdata, "POST") != NULL ) { // set update flag if POST request
00123         update=1;
00124     }
00125     if( strstr(webdata, "GET") != NULL && strstr(webdata, "favicon") == NULL ) { // set update flag for GET request but do not want to update for favicon requests
00126         update=1;
00127     }
00128 }
00129 // Starts webserver
00130 void startserver()
00131 {
00132     gettime();
00133     gettemp();
00134     getbattery();
00135     pc.printf("++++++++++ Resetting ESP ++++++++++\r\n");
00136     strcpy(cmdbuff,"node.restart()\r\n");
00137     SendCMD();
00138     wait(2);
00139     getreply();
00140     
00141     pc.printf("\n++++++++++ Starting Server ++++++++++\r\n> ");
00142 
00143     // initial values
00144     sprintf(cmdbuff, "count,time,analog1,analog2=0,\"%s\",\"%s\",\"%s\"\r\n",timebuf,Temp,Vcc);
00145     SendCMD();
00146     getreply();
00147     wait(0.5);
00148 
00149     //create server
00150     sprintf(cmdbuff, "srv=net.createServer(net.TCP,%d)\r\n",SERVtimeout);
00151     SendCMD();
00152     getreply();
00153     wait(0.5);
00154     strcpy(cmdbuff,"srv:listen(80,function(conn)\r\n");
00155     SendCMD();
00156     getreply();
00157     wait(0.3);
00158         strcpy(cmdbuff,"conn:on(\"receive\",function(conn,payload) \r\n");
00159         SendCMD();
00160         getreply();
00161         wait(0.3);
00162         
00163         //print data to mbed
00164         strcpy(cmdbuff,"print(payload)\r\n");
00165         SendCMD();
00166         getreply();
00167         wait(0.2);
00168        
00169         //web page data
00170         strcpy(cmdbuff,"conn:send('<!DOCTYPE html><html><body><h1>ESP8266 Mbed IoT Web Controller</h1>')\r\n");
00171         SendCMD();
00172         getreply();
00173         wait(0.4);
00174         strcpy(cmdbuff,"conn:send('Hit count: '..count..'')\r\n");
00175         SendCMD();
00176         getreply();
00177         wait(0.2);
00178         strcpy(cmdbuff,"conn:send('<br>Last hit (based on mbed RTC time): '..time..'<br><hr>')\r\n");
00179         SendCMD();
00180         getreply();
00181         wait(0.4);
00182         strcpy(cmdbuff,"conn:send('Analog 1: '..analog1..' V<br>Analog 2: '..analog2..' V<br><hr>')\r\n");
00183         SendCMD();
00184         getreply();
00185         wait(0.3);
00186         strcpy(cmdbuff,"conn:send('<form method=\"POST\"')\r\n");
00187         SendCMD();
00188         getreply();
00189         wait(0.3);
00190         strcpy(cmdbuff, "conn:send('<p><input type=\"checkbox\" name=\"check\" value=\"led1v\"> flip LED1')\r\n");
00191         SendCMD();
00192         getreply();
00193         wait(0.3);
00194         strcpy(cmdbuff, "conn:send('<p><input type=\"checkbox\" name=\"check\" value=\"led2v\"> flip LED2')\r\n");
00195         SendCMD();
00196         getreply();
00197         wait(0.3);
00198         strcpy(cmdbuff, "conn:send('<p><input type=\"checkbox\" name=\"check\" value=\"led3v\"> flip LED3')\r\n");
00199         SendCMD();
00200         getreply();
00201         wait(0.3);
00202         strcpy(cmdbuff, "conn:send('<p><input type=\"checkbox\" name=\"check\" value=\"led4v\"> flip LED4')\r\n");
00203         SendCMD();
00204         getreply();
00205         wait(0.3);
00206         strcpy(cmdbuff,"conn:send('<p><input type=\"submit\" value=\"send-refresh\"></form>')\r\n");
00207         SendCMD();
00208         getreply();
00209         wait(0.3);
00210         strcpy(cmdbuff, "conn:send('<p><h2>How to use:</h2><ul><li>Select a checkbox to flip on/off</li><li>Click Send-Refresh to send data and refresh values</li></ul></body></html>')\r\n");
00211         SendCMD();
00212         getreply();
00213         wait(0.5); 
00214         // end web page data
00215         strcpy(cmdbuff, "conn:on(\"sent\",function(conn) conn:close() end)\r\n"); // close current connection
00216         SendCMD();
00217         getreply();
00218         wait(0.3);
00219         strcpy(cmdbuff, "end)\r\n");
00220         SendCMD();
00221         getreply();
00222         wait(0.2);
00223     strcpy(cmdbuff, "end)\r\n");
00224     SendCMD();
00225     getreply();
00226     wait(0.2);
00227 
00228     strcpy(cmdbuff, "tmr.alarm(0, 1000, 1, function()\r\n");
00229     SendCMD();
00230     getreply();
00231     wait(0.2);
00232     strcpy(cmdbuff, "if wifi.sta.getip() == nil then\r\n");
00233     SendCMD();
00234     getreply();
00235     wait(0.2);
00236     strcpy(cmdbuff, "print(\"Connecting to AP...\\n\")\r\n");
00237     SendCMD();
00238     getreply();
00239     wait(0.2);
00240     strcpy(cmdbuff, "else\r\n");
00241     SendCMD();
00242     getreply();
00243     wait(0.2);
00244     strcpy(cmdbuff, "ip, nm, gw=wifi.sta.getip()\r\n");
00245     SendCMD();
00246     getreply();
00247     wait(0.2);
00248     strcpy(cmdbuff,"print(\"IP Address: \",ip)\r\n");
00249     SendCMD();
00250     getreply();
00251     wait(0.2);
00252     strcpy(cmdbuff,"tmr.stop(0)\r\n");
00253     SendCMD();
00254     getreply();
00255     wait(0.2);
00256     strcpy(cmdbuff,"end\r\n");
00257     SendCMD();
00258     getreply();
00259     wait(0.2);
00260     strcpy(cmdbuff,"end)\r\n");
00261     SendCMD();
00262     getreply();
00263     wait(0.2);
00264     
00265     pc.printf("\n\n++++++++++ Ready ++++++++++\r\n\n");
00266 }
00267 
00268 
00269 // ESP Command data send
00270 void SendCMD()
00271 {
00272     int i;
00273     char temp_char;
00274     bool empty;
00275     i = 0;
00276 // Start Critical Section - don't interrupt while changing global buffer variables
00277     NVIC_DisableIRQ(UART1_IRQn);
00278     empty = (tx_in == tx_out);
00279     while ((i==0) || (cmdbuff[i-1] != '\n')) {
00280 // Wait if buffer full
00281         if (((tx_in + 1) % buffer_size) == tx_out) {
00282 // End Critical Section - need to let interrupt routine empty buffer by sending
00283             NVIC_EnableIRQ(UART1_IRQn);
00284             while (((tx_in + 1) % buffer_size) == tx_out) {
00285             }
00286 // Start Critical Section - don't interrupt while changing global buffer variables
00287             NVIC_DisableIRQ(UART1_IRQn);
00288         }
00289         tx_buffer[tx_in] = cmdbuff[i];
00290         i++;
00291         tx_in = (tx_in + 1) % buffer_size;
00292     }
00293     if (esp.writeable() && (empty)) {
00294         temp_char = tx_buffer[tx_out];
00295         tx_out = (tx_out + 1) % buffer_size;
00296 // Send first character to start tx interrupts, if stopped
00297         esp.putc(temp_char);
00298     }
00299 // End Critical Section
00300     NVIC_EnableIRQ(UART1_IRQn);
00301     return;
00302 }
00303 
00304 // Get Command and ESP status replies
00305 void getreply()
00306 {
00307     read_line();
00308     sscanf(rx_line,replybuff);
00309 }
00310  
00311 // Read a line from the large rx buffer from rx interrupt routine
00312 void read_line() {
00313     int i;
00314     i = 0;
00315 // Start Critical Section - don't interrupt while changing global buffer variables
00316     NVIC_DisableIRQ(UART1_IRQn);
00317 // Loop reading rx buffer characters until end of line character
00318     while ((i==0) || (rx_line[i-1] != '\r')) {
00319 // Wait if buffer empty
00320         if (rx_in == rx_out) {
00321 // End Critical Section - need to allow rx interrupt to get new characters for buffer
00322             NVIC_EnableIRQ(UART1_IRQn);
00323             while (rx_in == rx_out) {
00324             }
00325 // Start Critical Section - don't interrupt while changing global buffer variables
00326             NVIC_DisableIRQ(UART1_IRQn);
00327         }
00328         rx_line[i] = rx_buffer[rx_out];
00329         i++;
00330         rx_out = (rx_out + 1) % buffer_size;
00331     }
00332 // End Critical Section
00333     NVIC_EnableIRQ(UART1_IRQn);
00334     rx_line[i-1] = 0;
00335     return;
00336 }
00337  
00338  
00339 // Interupt Routine to read in data from serial port
00340 void Rx_interrupt() {
00341     DataRX=1;
00342     //led3=1;
00343 // Loop just in case more than one character is in UART's receive FIFO buffer
00344 // Stop if buffer full
00345     while ((esp.readable()) && (((rx_in + 1) % buffer_size) != rx_out)) {
00346         rx_buffer[rx_in] = esp.getc();
00347 // Uncomment to Echo to USB serial to watch data flow
00348         pc.putc(rx_buffer[rx_in]);
00349         rx_in = (rx_in + 1) % buffer_size;
00350     }
00351     //led3=0;
00352     return;
00353 }
00354  
00355  
00356 // Interupt Routine to write out data to serial port
00357 void Tx_interrupt() {
00358     //led2=1;
00359 // Loop to fill more than one character in UART's transmit FIFO buffer
00360 // Stop if buffer empty
00361     while ((esp.writeable()) && (tx_in != tx_out)) {
00362         esp.putc(tx_buffer[tx_out]);
00363         tx_out = (tx_out + 1) % buffer_size;
00364     }
00365     //led2=0;
00366     return;
00367 }
00368 
00369 void gettime()
00370 {
00371     time_t seconds = time(NULL);
00372     strftime(timebuf,50,"%H:%M:%S %a %d %b %y", localtime(&seconds));
00373 }
00374 
00375 void setRTC()
00376 {
00377     t.tm_sec = (0);             // 0-59
00378     t.tm_min = (minute);        // 0-59
00379     t.tm_hour = (hour);         // 0-23
00380     t.tm_mday = (dayofmonth);   // 1-31
00381     t.tm_mon = (month-1);       // 0-11  "0" = Jan, -1 added for Mbed RCT clock format
00382     t.tm_year = ((year)+100);   // year since 1900,  current DCF year + 100 + 1900 = correct year
00383     set_time(mktime(&t));       // set RTC clock
00384 }
00385 // Analog in example
00386 void getbattery()
00387 {
00388     AdcIn=Ain1.read();
00389     Ht = (AdcIn*3.3); // set the numeric to the exact MCU analog reference voltage for greater accuracy
00390     sprintf(Vcc,"%2.3f",Ht);
00391 }
00392 // Temperature example
00393 void gettemp()
00394 {
00395  
00396     AdcIn=Ain2.read();
00397     Ht = (AdcIn*3.3); // set the numeric to the exact MCU analog reference voltage for greater accuracy  
00398     sprintf(Temp,"%2.3f",Ht);
00399 }