Turning on a relay while using millis()

Projects Programming
1

I have a terrarium code that works and I want to add a water pump to it. I will control the water pump using a relay. Given the size of my plant I want the water pump to only turn on once a day for 5 seconds. All the other actions on my terrarium work using if statements.

I am using a MEGA 2560. My circuit is as follows:

  • A0 = light sensor (not currently used for anything; it's too finicky)
  • A1 = soil humidity sensor
  • Pin 5, 6, 7 = RTC (RST, Dat, CLK , respectively)
  • Pin 9, 10, 11 = RGB led (displays the soil humidity using light color)
  • Pin 22 = DHT
  • Pin 31, 33, 35, 37 = 4 relay module
  • Pin 41, 43, 45, 47, 49, 51 = LCD connections

Part numbers are as follows:

  • RTC = DS1302
  • DHT = DHT11
  • Relays = 4 channel module
  • Soil humidity sensor = I actually don't have this one, but it's a standard one (?)
  • Fans = CPU fans connected to a 24V converter and plugged into relay
  • LCD is a 2x16

I am trying to add a section of code so that relay1 runs power to the water pump and it turns on for 5 seconds at 8 am. To do this I wrote a water pump code as it's own sketch (sort of a mini version of my working terrarium sketch). However, the relay condition doesn't change when running the code:

#include <virtuabotixRTC.h> //real clock
int relay1 = 31;
virtuabotixRTC myRTC(7, 6, 5);


unsigned long startMillis;
unsigned long currentMillis;
const unsigned long period = 10000; //will be 10 mins = 600000 ms

unsigned long waterMillis;
unsigned long currentwaterMillis;
const unsigned long waterperiod = 5000;

bool wateredToday = false;

void setup() {
  Serial.begin(9600); // Initializes Serial Monitor
  pinMode(relay1,OUTPUT);
  digitalWrite(relay1,LOW);
}

void loop() {
currentMillis = millis();
if (currentMillis - startMillis >= period){
  myRTC.updateTime();
  
  /* Turn on relay1 for 5 seconds. Also, when the waterpump turns on change the boolean condition for the next hour such that it doesn't turn on again */
 
 if ((myRTC.hours == 8) && (wateredToday = false)){
    digitalWrite(relay1,HIGH);
    wateredToday == true;
    currentwaterMillis = millis();
    if (currentwaterMillis - waterMillis >= waterperiod){
    digitalWrite(relay1,LOW);
    }
  }
  else {
    digitalWrite(relay1,LOW);
    }

    if (myRTC.hours > 9){
      wateredToday = false;}
      else {wateredToday = true;}
   
  // Print to serial monitor
   Serial.print("\nCurrent Date / Time: ");
   Serial.print(myRTC.dayofmonth); 
   Serial.print("/");
   Serial.print(myRTC.month);
   Serial.print("/");
   Serial.print(myRTC.year);
   Serial.print(" ");
   Serial.print(myRTC.hours);
   Serial.print(":");
   Serial.print(myRTC.minutes);
   Serial.print(":");
   Serial.println(myRTC.seconds);
   Serial.print(wateredToday, DEC); //prints the condition of the bool
  
   startMillis = currentMillis; //This the overall code refresh period
  }

}

Can anyone tell what I'm doing wrong? Does anyone have better suggestions on how to do this?

Thanks

2

a very classic mistake:

 if ((myRTC.hours == 8) && (wateredToday = false)){

you are assigning the value 'false' to wateredToday, not testing whether is is false or not ( == vs. = )
and since you are assigning the value, the if statement is always false.