Dhrumil Makadia
Published © CC BY

Monitor Tank Water Level or Distance on Your Desktop

Using Wemos D1, an ultrasonic sensor and Thingio.AI IoT platform.

IntermediateProtip30 minutes956
Monitor Tank Water Level or Distance on Your Desktop

Things used in this project

Hardware components

Wemos D1
×1
Ultrasonic Sensor - HC-SR04 (Generic)
Ultrasonic Sensor - HC-SR04 (Generic)
×1
Male/Female Jumper Wires
Male/Female Jumper Wires
×1

Software apps and online services

Thingsio.ai

Story

Read more

Schematics

Diagram

Step by step Process

Code

Code

Arduino
#include <SoftwareSerial.h>
SoftwareSerial mySerial(12, 13); // RX, TX

#include <ESP8266WiFi.h>          //https://github.com/esp8266/Arduino
#include <DNSServer.h>
#include <ESP8266WebServer.h>
#include "WiFiManager.h"          //https://github.com/tzapu/WiFiManager

int count=0,i,m,j,k;
int t,t1,t2,t3;
int outputpin= A0;//ds18b20 

const int trigPin = D7;
const int echoPin = D6;
long duration;
int distance,d1;

//////////////////////////////////////// ALL DECLARATIONS for CLOUD //////////////////////////////
const char* host = "api.thingsio.ai";                                 // OR host = devapi2.thethingscloud.com
const char* post_url = "/devices/deviceData";       // OR /api/v2/thingscloud2/_table/data_ac
const char* time_server = "www.convert-unix-time.com";             //this is to convert timestamp
const int httpPort = 80;

char timestamp[10];

WiFiClient client;
  


/////////////////////////////////////////////////////////////////////////////////////////////////////////
void configModeCallback (WiFiManager *myWiFiManager) 
{
  Serial.println("Entered config mode");             //*-*-*-*-*-*-*-*-*-*-*-*-*-*if control enters this function then net is not connected
  Serial.println(WiFi.softAPIP());                  // "WiFi.softAPIP() is for AP" , "WiFi.localIP() is for STA",
                                                                
  Serial.println(myWiFiManager->getConfigPortalSSID());             //if you used auto generated SSID, print it
}
/////////////////////////////////////// TIMESTAMP CALCULATION function///////////////////////////////////////
int GiveMeTimestamp()
{
  unsigned long timeout = millis();

  while (client.available() == 0)
  {
    if (millis() - timeout > 50000)
    {
      client.stop();
      return 0;
    }
  }

while (client.available())
      {
        String line = client.readStringUntil('\r');                    //indexOf() is a funtion to search for smthng , it returns -1 if not found
        int pos = line.indexOf("\"timestamp\"");                       //search for "\"timestamp\"" from beginning of response got and copy all data after that , it'll be your timestamp
        if (pos >= 0)                                                     
        {
          int j = 0;
          for(j=0;j<10;j++)
          {
            timestamp[j] = line[pos + 12 + j];
          }
        }
      }
}  
////////////////////////////////////////////////////////////////////////////////////////////////////////

void setup() 
{
  pinMode(trigPin, OUTPUT); // Sets the trigPin as an Output
  pinMode(echoPin, INPUT); // Sets the echoPin as an Input
  Serial.begin(115200);     //(19200,SERIAL_8E1) - data size = 8 bits , parity = Even , stop bit =  1bit
mySerial.begin(115200);
  WiFiManager wifiManager;
 
  wifiManager.setAPCallback(configModeCallback);
                                                                                                    
  if(!wifiManager.autoConnect("xxxxxxxxxxxx","xxxxxxxxxxx"))                   //wifiManager.autoConnect("AP-NAME", "AP-PASSWORD"); (OR) wifiManager.autoConnect("AP-NAME"); only ID no password (OR) wifiManager.autoConnect(); this will generate a ID by itself
  {
    Serial.println("failed to connect and hit timeout");     //control comes here after long time of creating Access point "NodeMCU" by NodeMCU and still it has not connected
    //reset and try again, or maybe put it to deep sleep
    ESP.reset();
    delay(1000);
  } 

  //if you come here you have connected to the WiFi
  Serial.println("connected... :");
 
}

void loop() 
{
/////////////////////////////////////// SEND THE QUERY AND RECEIVE THE RESPONSE///////////////////////  
  
  digitalWrite(trigPin, LOW);
  delayMicroseconds(2);
  digitalWrite(trigPin, HIGH);
  delayMicroseconds(10);
  digitalWrite(trigPin, LOW);
  duration = pulseIn(echoPin, HIGH);
  distance = int(duration*0.034/2);       

  Serial.print("connecting to ");
  Serial.println(host);                          //defined upside :- host = devapi2.thethingscloud.com or 139.59.26.117

///////////////////////////////////// TIMESTAMP CODE SNIPPET /////////////////////////
  Serial.println("inside get timestamp\n");
  if (!client.connect(time_server, httpPort)) 
  {
    return;                                                        //*-*-*-*-*-*-*-*-*-*
  }

  client.println("GET /api?timestamp=now HTTP/1.1");                            //Whats this part doing, i didnt get
  client.println("Host: www.convert-unix-time.com");
  client.println("Cache-Control: no-cache");
  client.println("Postman-Token: ea3c18c6-09ba-d049-ccf3-369a22a284b8");
  client.println();

GiveMeTimestamp();                        //it'll call the function which will get the timestamp response from the server
Serial.println("timestamp receieved");
Serial.println(timestamp);
///////////////////////////////////////////////////////////////////////////////

// Use WiFiClient class to create TCP connections
  if (!client.connect(host, httpPort))            //host = devapi2.thethingscloud.com , port = 80
  {
    Serial.println("connection failed");                  // *-*-*-*-*-*--*-*-*-*-*-*-*-*-*-*-*-*-
    return;
  }
  
  client.print("Content-Length: ");
  client.println(); 

  unsigned long timeout = millis();
  while (client.available() == 0) 
  {
    if (millis() - timeout > 50000) 
    {
      Serial.println(">>> Client Timeout !");
      client.stop();
      return;
    }
  }
  
  Serial.println("***********************************************");
  Serial.println();
  Serial.println("closing connection");

  Serial.println("inside ThingsCloudPost");

 
  String PostValue = "{\"device_id\": xxxxxx, \"slave_id\": x"; //your ids
         PostValue = PostValue + ",\"dts\":" +timestamp;
   PostValue = PostValue +",\"data\":{\"Centimeter\":" + distance +",\"CM\":" + distance +"}"+"}";
  
  
  Serial.println(PostValue);

//////////////////////////////// try to connect to server again and POST the data on the cloud //////////////////////////
  if (!client.connect(host, httpPort)) 
  {
    return;
  }

  client.print("POST ");
  client.print(post_url);               /// POST api/device-datas         HTTP/1.1     Host: baas.thethingscloud.com      Content-Type: application/json        Cache-Control: no-cache
  client.println(" HTTP/1.1");           //Authorization:          Content-Length: 
  client.print("Host: ");
  client.println(host);
  client.println("Content-Type: application/json");
  client.println("Cache-Control: no-cache");
  client.print("Authorization: Bearer eyJ0eXAiOiJKV1QiLCJhbGciOiJIUzI1NiJ9.IjViZTc5ZjRiNDAyYjlkNGI5MDdiZGRmZCI.hBa2XTagbf56p_E83PeMZHaoJO4EUrbwGcmWTU0j0-w");
  client.println();
  client.print("Content-Length: ");
  client.println(PostValue.length());
  client.println();
  client.println(PostValue);
  
//////////////////////////////////POSTING the data on to the cloud is done and now get the response form cloud server//////////////////
  while (client.available() == 0) 
  {
    if (millis() - timeout > 50000) 
    {
      Serial.println(">>> Client Timeout !");
      client.stop();
      return;
    }
  }
  
  Serial.println("Response From Server");
  while(client.available())
  { 
    String line2 = client.readStringUntil('\r');   
    Serial.print(line2);
    
  }
Serial.println();    
Serial.println("//////////////////////    THE END     /////////////////////");
delay(3000);
}

Credits

Dhrumil Makadia

Dhrumil Makadia

37 projects • 40 followers

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