NodemMCU-01 webserver function unstable (sometimes getting stuck in the loop)

zazas321 · Feb 27, 2019

Hello. I am working on a big scale project and I have been having a lot of problems integrating few different codes together. I have tested different functions seperately and they all seem to work fine. When I put it all together, there is one massive problem that I get and I cannot seem to fix it.

I am hosting a webserver with an NodeMCU chip to toggle digital pin from the internet on the remote Xbee device. At the same time, I got another remote Xbee device that is sending me remote temperature reading. Once uploaded, the program works perfectly fine, until I open the web browser and input the IP address to connect to the webserver. As soon as the webserver is opened, the Arduino seems to be stuck in a loop waiting for me to press the button to toggle the device ON and OFF. After toggling the device, the loop starts again and program is waiting for me to press the button but is not executing any other functions in the void(loop).

All code:

C:

// Load Wi-Fi library
#include <ESP8266WiFi.h>


#include <Adafruit_INA219.h>
Adafruit_INA219 ina219;
#include <Arduino.h>

#include "DHT.h"
#define DHTPIN 2 //D4 pin of nodemcu
#define DHTTYPE DHT22   // DHT 22  (AM2302), AM2321
#include <Arduino.h>
#include <U8g2lib.h>
#ifdef U8X8_HAVE_HW_SPI
#include <SPI.h>
#endif
#ifdef U8X8_HAVE_HW_I2C
#include <Wire.h>
#endif



// Replace with your network credentials
const char* ssid     = "PLUSNET-HNHJ";
const char* password = "xxxxxxxxx";

// Set web server port number to 80
WiFiServer server(80);

// Variable to store the HTTP request
String header;

// Auxiliar variables to store the current output state
String output5State = "off";
String output4State = "off";

// Assign output variables to GPIO pins
//const int output5 = 16;
//const int output4 = 12;

U8G2_SH1106_128X64_NONAME_F_4W_HW_SPI u8g2(U8G2_R0, /* cs=*/ 15, /* dc=*/ 16, /* reset=*/ 0 );
//HADRWARE SPI MOSI D7, CLK D5
DHT dht(DHTPIN, DHTTYPE);
float temp;

void setup() {
  Serial.begin(9600);
u8g2.begin();
  dht.begin();
  ina219.begin();
  // Connect to Wi-Fi network with SSID and password
  Serial.print("Connecting to ");
  Serial.println(ssid);
  WiFi.begin(ssid, password);
  while (WiFi.status() != WL_CONNECTED) {
    delay(500);
    Serial.print(".");
  }
  // Print local IP address and start web server
  Serial.println("");
  Serial.println("WiFi connected.");
  Serial.println("IP address: ");
  Serial.println(WiFi.localIP());
  server.begin();


}

void loop(){


Remotetemperature();

roomtemperature();
//powersensor();


WEB_DISPLAY();



}




void serialFlushx(){
  while(Serial.available() > 0) {
    char t = Serial.read();
  }
}







void roomtemperature(){
  float h = dht.readHumidity();
float t = dht.readTemperature();
if (isnan(h) || isnan(t))
return;
//u8g2.clearBuffer();          // clear the internal memory
u8g2.setFont(u8g2_font_t0_11_tf);
u8g2.setCursor(0, 10);
u8g2.println("Temperature:");
u8g2.print(t);
u8g2.print(" ");
u8g2.print("C");
u8g2.setFont(u8g2_font_t0_11_tf);
u8g2.setCursor(0, 20);
u8g2.println("Humiditys:");
u8g2.print(h);
u8g2.print(" ");
u8g2.print("%");
delay(10);
u8g2.setFont(u8g2_font_t0_11_tf);
u8g2.setCursor(0, 30);
u8g2.println("LED1:");
u8g2.sendBuffer();

}


void WEB_DISPLAY(){


  WiFiClient client = server.available();   // Listen for incoming clients

  if (client) {                             // If a new client connects,
    Serial.println("New Client.");          // print a message out in the serial port
    String currentLine = "";                // make a String to hold incoming data from the client
    while (client.connected()) {            // loop while the client's connected
      if (client.available()) {             // if there's bytes to read from the client,
        char c = client.read();             // read a byte, then
        Serial.write(c);                    // print it out the serial monitor
        header += c;
        if (c == '\n') {                    // if the byte is a newline character
          // if the current line is blank, you got two newline characters in a row.
          // that's the end of the client HTTP request, so send a response:
          if (currentLine.length() == 0) {
            // HTTP headers always start with a response code (e.g. HTTP/1.1 200 OK)
            // and a content-type so the client knows what's coming, then a blank line:
            client.println("HTTP/1.1 200 OK");
            client.println("Content-type:text/html");
            client.println("Connection: close");
            client.println();
         
            // turns the GPIOs on and off
            if (header.indexOf("GET /5/on") >= 0) {
              Serial.println("GPIO 5 on");
              output5State = "on";
              setRemoteState(0x5);
              u8g2.clearBuffer();
              u8g2.setFont(u8g2_font_t0_11_tf);
              u8g2.setCursor(30, 30);
              u8g2.print("ON");
             
           
           
           
           
            } else if (header.indexOf("GET /5/off") >= 0) {
              Serial.println("GPIO 5 off");
              output5State = "off";
              setRemoteState(0x4);
              u8g2.clearBuffer();          // clear the internal memory
              u8g2.setFont(u8g2_font_t0_11_tf);
              u8g2.setCursor(30, 30);
              u8g2.print("OFF");
           
           
            }
         
              u8g2.sendBuffer();
       
         
            // Display the HTML web page
            client.println("<!DOCTYPE html><html>");
            client.println("<head><meta name=\"viewport\" content=\"width=device-width, initial-scale=1\">");
            client.println("<link rel=\"icon\" href=\"data:,\">");
            // CSS to style the on/off buttons
            // Feel free to change the background-color and font-size attributes to fit your preferences
            client.println("<style>html { font-family: Helvetica; display: inline-block; margin: 0px auto; text-align: center;}");
            client.println(".button { background-color: #195B6A; border: none; color: white; padding: 16px 40px;");
            client.println("text-decoration: none; font-size: 30px; margin: 2px; cursor: pointer;}");
            client.println(".button2 {background-color: #77878A;}</style></head>");
         
            // Web Page Heading
            client.println("<body><h1>ESP8266 Web Server</h1>");
         
            // Display current state, and ON/OFF buttons for GPIO 5
            client.println("<p>GPIO 5 - State " + output5State + "</p>");
            // If the output5State is off, it displays the ON button     
            if (output5State=="off") {
              client.println("<p><a href=\"/5/on\"><button class=\"button\">ON</button></a></p>");
            } else {
              client.println("<p><a href=\"/5/off\"><button class=\"button button2\">OFF</button></a></p>");
            }
             
         
         
            // The HTTP response ends with another blank line
            client.println();
            // Break out of the while loop
            break;
          } else { // if you got a newline, then clear currentLine
            currentLine = "";
          }
        } else if (c != '\r') {  // if you got anything else but a carriage return character,
          currentLine += c;      // add it to the end of the currentLine
        }
      }
    }
    // Clear the header variable
    header = "";
    // Close the connection
    client.stop();
    Serial.println("Client disconnected.");
    Serial.println("");
  }
}





//XBEE S2C
void setRemoteState (char value){

//while(Serial.available()){  //is there anything to read?
//char getData = Serial.read();  //if yes, read it
    } 
  Serial.write(0x7E); //start byte
  Serial.write((byte)0x0); //high part of length (always zero)
  Serial.write(0x10);  //low part of length
  Serial.write(0x17); //0x17 is remote AT command
    Serial.write((byte)0x0);  //frame ID set to zero for no reply

  //ID of recipient, or use 0xFFFF for broadcast
  Serial.write(0x00);
  Serial.write(0x13);
  Serial.write(0xA2);
  Serial.write(0x00);
  Serial.write(0x41);
  Serial.write(0x82);
  Serial.write(0xD1);
  Serial.write(0xB9);
  //16 bit of recipient of 0xFFFE
  Serial.write(0x2D);
  Serial.write(0xCD);
  Serial.write(0x02);

  Serial.write('D');
  Serial.write('4');


  //command data in as many bytes
  Serial.write(value);
  //checksum
  long sum = 0x17 + 0x13 + 0xA2 + 0x41 + 0x82+0xD1+0xB9+0x2D+0xCD + 0x02 + 'D' + '4' + value;
  Serial.write(0xFF - (sum & 0xFF));
  serialFlushx();
}






void Remotetemperature(){

  if (Serial.available()>21 &&  Serial.available()<23  ){
if (Serial.read()==0x7E){
  for(int i=1;i<19;i++){
    byte discardByte = Serial.read();
  }
   int analogMSB=Serial.read();
   int analogLSB= Serial.read();
  if (isnan(analogMSB) || isnan(analogLSB))
  byte discardByte;
   int analogReading =analogLSB+(analogMSB*256);
   if (analogReading >0 && analogReading<1024)
    temp=(analogReading/1023.0)*120;
    Serial.print(temp);
   Serial.println("degrees C");

  }

u8g2.setFont(u8g2_font_t0_11_tf);
u8g2.setCursor(0, 40);
u8g2.println("Outside_temp:");
u8g2.print(temp);
u8g2.print(" ");
u8g2.print("C");
u8g2.sendBuffer();

// THIS IS VERY IMPORTANT!!!! CLEAR SERIAL PORT EVERYTIME THE API FRAME DATA IS READ
serialFlushx();


}


}




void powersensor(){

  float shuntvoltage = 0;
  float busvoltage = 0;
  float current_mA = 0;
  float loadvoltage = 0;
  float power_mW = 0;


busvoltage = ina219.getBusVoltage_V();
current_mA = ina219.getCurrent_mA();

u8g2.setFont(u8g2_font_t0_11_tf);
u8g2.setCursor(0, 50);
u8g2.println("Voltage:");
u8g2.print(busvoltage);
u8g2.print(" ");
u8g2.print("V");

u8g2.setCursor(0, 60);
u8g2.println("Current:");
u8g2.print(current_mA);
u8g2.print(" ");
u8g2.print("mA");
u8g2.sendBuffer();
delay(1000);


}

I believe the program lies in this function:

C:

void WEB_DISPLAY(){


  WiFiClient client = server.available();   // Listen for incoming clients

  if (client) {                             // If a new client connects,
    Serial.println("New Client.");          // print a message out in the serial port
    String currentLine = "";                // make a String to hold incoming data from the client
    while (client.connected()) {            // loop while the client's connected
      if (client.available()) {             // if there's bytes to read from the client,
        char c = client.read();             // read a byte, then
        Serial.write(c);                    // print it out the serial monitor
        header += c;
        if (c == '\n') {                    // if the byte is a newline character
          // if the current line is blank, you got two newline characters in a row.
          // that's the end of the client HTTP request, so send a response:
          if (currentLine.length() == 0) {
            // HTTP headers always start with a response code (e.g. HTTP/1.1 200 OK)
            // and a content-type so the client knows what's coming, then a blank line:
            client.println("HTTP/1.1 200 OK");
            client.println("Content-type:text/html");
            client.println("Connection: close");
            client.println();
         
            // turns the GPIOs on and off
            if (header.indexOf("GET /5/on") >= 0) {
              Serial.println("GPIO 5 on");
              output5State = "on";
              setRemoteState(0x5);
              u8g2.clearBuffer();
              u8g2.setFont(u8g2_font_t0_11_tf);
              u8g2.setCursor(30, 30);
              u8g2.print("ON");
             
           
           
           
           
            } else if (header.indexOf("GET /5/off") >= 0) {
              Serial.println("GPIO 5 off");
              output5State = "off";
              setRemoteState(0x4);
              u8g2.clearBuffer();          // clear the internal memory
              u8g2.setFont(u8g2_font_t0_11_tf);
              u8g2.setCursor(30, 30);
              u8g2.print("OFF");
           
           
            }
         
              u8g2.sendBuffer();
       
         
            // Display the HTML web page
            client.println("<!DOCTYPE html><html>");
            client.println("<head><meta name=\"viewport\" content=\"width=device-width, initial-scale=1\">");
            client.println("<link rel=\"icon\" href=\"data:,\">");
            // CSS to style the on/off buttons
            // Feel free to change the background-color and font-size attributes to fit your preferences
            client.println("<style>html { font-family: Helvetica; display: inline-block; margin: 0px auto; text-align: center;}");
            client.println(".button { background-color: #195B6A; border: none; color: white; padding: 16px 40px;");
            client.println("text-decoration: none; font-size: 30px; margin: 2px; cursor: pointer;}");
            client.println(".button2 {background-color: #77878A;}</style></head>");
         
            // Web Page Heading
            client.println("<body><h1>ESP8266 Web Server</h1>");
         
            // Display current state, and ON/OFF buttons for GPIO 5
            client.println("<p>GPIO 5 - State " + output5State + "</p>");
            // If the output5State is off, it displays the ON button     
            if (output5State=="off") {
              client.println("<p><a href=\"/5/on\"><button class=\"button\">ON</button></a></p>");
            } else {
              client.println("<p><a href=\"/5/off\"><button class=\"button button2\">OFF</button></a></p>");
            }
             
         
         
            // The HTTP response ends with another blank line
            client.println();
            // Break out of the while loop
            break;
          } else { // if you got a newline, then clear currentLine
            currentLine = "";
          }
        } else if (c != '\r') {  // if you got anything else but a carriage return character,
          currentLine += c;      // add it to the end of the currentLine
        }
      }
    }
    // Clear the header variable
    header = "";
    // Close the connection
    client.stop();
    Serial.println("Client disconnected.");
    Serial.println("");
  }
}

Serial monitor:

If I close the web browser and restart NodeMCU, system starts working as normal so the problem must be with the function described above:/

Any suggestions?

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NodemMCU-01 webserver function unstable (sometimes getting stuck in the loop)

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NodemMCU-01 webserver function unstable (sometimes getting stuck in the loop)

zazas321

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