1

vI have this functions in my loop() and it publishes temperature reading to Ubidots(an IoT cloud service) using the #include library but it seems it returns a boolean and so the loop is delayed until a true or false value is return and this takes a while there by slowing down my loop() function and other functions in it. Is there a way I can call this function without it having to slow the loop?

#include <math.h>
#include <Wire.h>
#include <Servo.h> 
#include <WiFi.h>
#include <Ubidots.h>
#include "rgb_lcd.h"
#include "Timer.h"
//#include <SoftwareSerial.h>

//SoftwareSerial mySerial(11, 10); // RX, TX


char ssid[] = "ROSTALECOM_6916";                                                 //your network SSID (name) 
char pass[] = "6PTDFYJD";                                                         //your network password (use for WPA, or use as key for WEP)
String api = "875c4a17d995ce4977bdfc1ace55233fd0591c7ce";                             //your API Key number
String idvari = "567d623a762542205cbc517f";                                          //the number of the Ubidots variable
String ctext = "{\"color\":\"blue\",\"status\":\"active\"}";
Ubidots ubiclient(api);                                                             //with that you call the api with the prefix ubiclient

byte p5[8] = {
  0x1F,
  0x1F,
  0x1F,
  0x1F,
  0x1F,
  0x1F,
  0x1F,
  0x1F
  };

int a;
int temperature;
int B=3975;                  //B value of the thermistor
float resistance;

String readString;
int val;
int hum = 70.35;
unsigned char base = 10;

//Temperature Limits
int maxTemp = 29;
int minTemp = 28.5;

//Declarations
rgb_lcd lcd;
Servo winServo;

//Ubidots timer
Timer t;

void setup() 
{    
    //Loading character
    lcd.createChar(0, p5);

Serial1.begin(9600);
Serial.begin(9600); 
winServo.attach(3);
lcd.begin(16, 2);
//mySerial.begin(9600);


//Start Screen
lcd.print("--SmartGarden--");
for (int i = 0; i < 16; i++) 
{
        // scroll one position left:
        lcd.setCursor(i, 1);
        lcd.write((uint8_t)0);
        delay(400);
 }
lcd.clear();
lcd.print("Connecting...");
//connect to  wifi network
boolean response;                                                                
int status = WL_IDLE_STATUS;                                                                                                          
response = ubiclient.WifiCon(ssid, pass, status, api);                            
Serial.println(response);

//
t.every(1000, sendToUbi);

}


void readTemp()
{
   a=analogRead(0);
   resistance=(float)(1023-a)*10000/a;  
   temperature=1/(log(resistance/10000)/B+1/298.15)-273.15;

   //Send temperature via Bluetooth
   Serial.print(temperature);

   //print temperature to LCD
   lcd.clear();
   lcd.setCursor(0,0);
   lcd.print("Tmp:");
   lcd.print(temperature);
   //print humidity to LCD
   lcd.setCursor(8,0);
   lcd.print("Hm:");
   lcd.print("50");

   delay(1000);

}
void writeServo()
 {
  if (val != 0)
  {  
  //val = map(val, 0, 1023, 0, 180);     
  winServo.write(val);                  
  delay(100);    
  } 
 } 

 void sendToUbi()
 {
 ubiclient.save_value(idvari, String(temperature));                                                  //this function is to post to ubidots and return True or False depending on the connection status
 Serial.println("The sensor value " + String(temperature) + " was sent to Ubidots");                //print the sensor value     
 }                    

void timerMax()
{
  for (int i = 0; i < 60; i++) 
  {

   }
   winServo.write(180);
 }

void loop() 
{
  //read temperature
  readTemp();

  //Update ubidots timer
   t.update();

  while (Serial1.available()) {
    delay(3);  
    char c = Serial1.read();
    readString += c; 
  }
  if (readString.length() >0)
    {
      Serial.println(readString);
      delay(15);

       val = readString.toInt();
       if (val != 0)
       {  
       //val = map(val, 0, 1023, 0, 180);     
        winServo.write(val);                  
       delay(100); 
       readString = "";   
       } 
       //writeServo();


    if (readString == "1")     
       {
        digitalWrite(13, HIGH);
       }
     if (readString == "0")
       {
        digitalWrite(13, LOW);
       }
     readString = "";
  } 

  if (temperature >= maxTemp)
  {
    timerMax();

  }

}
  • Please edit your post and format the code using the code formatting markdown (four leading spaces). For help see Markdown help. You should be able to do this by selecting the code and pressing Ctrl+K to have your browser do this for you. – Majenko Jan 27 '16 at 21:18
  • Please edit your post and add links to the libraries you are using. Without these libraries it is very hard for anyone else to understand your code. – Majenko Jan 27 '16 at 21:19
  • Please edit your post and remove confidential API tokens. :D – IOB Toolkit Team Jan 27 '16 at 22:22
  • The tokens were all edited and invalid – DannyGH Jan 28 '16 at 0:41
2

How to avoid delays in the loop() function?

The question is why all the delays? Is there some logic missing? What are you trying to design?

Using delays is often a sign of an attempt to synchronize with external events. Wait for additional input, etc.

Let us walk through some of them:

void readTemp()
{
   ...
  delay(1000);
}

What is this about? The function does read an analog input BUT then there is a lot of output to Serial and LCD and last this delay. Why?

void writeServo()
{
  ...                
 delay(100);    
} 

Again the same pattern. Now for your question "delays in the loop()".

void loop() 
{
   readTemp(); // hidden 1000 ms delay

  while (Serial1.available()) {
    delay(3);  
    ... 
  }
  if (readString.length() >0)
  {
     ...
     delay(15);
     ...
     if (val != 0)
     {  
       winServo.write(val);  // Possible hidden 100 ms delay                
       delay(100); 
       ...
     } 
     ...
}

Consider using some logic instead of the delays. There seem to be a common pattern you are using.

0

As short reply and a general note, there is the millis() function that will be faster than a delay(). It returns the number of milliseconds since the Arduino board began running the current program. You use maths to check if you've waited long enough.

Like this:

  // check to see if it's time to do something; that is, if the
  // difference between the current time and last time you blinked
  // the LED is bigger than the interval at which you want to
  // blink the LED.
  unsigned long currentMillis = millis();

  if (currentMillis - previousMillis >= interval) {
    // save the last time you blinked the LED
    previousMillis = currentMillis;

    // do something after the waiting interval here

   }

Edit: One should also be aware of Interrupts, but be warned they must be used correctly.

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