Automatic Plant Watering System Using Particle Photons

//This code was created for a project for UNCC's Instrumentation and Measurement class.

//The code is one part of a two Particle system that waters a plant based on data from a moisture sensor.

//Define Servo Name and Servo Pin.
Servo Servo1;
#define motor A4

//Motor States
    //ON: The motor depresses the tap of a tank, allowing water to drip onto the plant.
    //OFF: The tap of the tank is release, so no water drips onto the plant.
    
int ONStatePos = 50; //Position of the ON state
int OFFStatePos = 0; //Position of the OFF state

//Intialize Activation Time, or the time (in seconds) since the program started, to "activate" the motor (turn the motor from the OFF state to the ON state)
unsigned long delayActivate = 5; //Amount of time to delay the system when the signal changes to "wet" to "dry", this is to ensure the values are not effected by noise.
unsigned long ActivationTime = delayActivate; //The initial value of the Activation Time is set to delayActivate, this is to ensure the particle recieves accurate signals.

//Constant Timer Control Variables
int OnDuration = 2; //The amount of time (in seconds) the motor remain in the ON state
int waitDuration = 30; //The amount of time (in seconds) the motor waits when in the OFF state to turn back to the ON state

void setup() {
    Servo1.attach(A4); //Attach the Servo to Analog Output Pin
    
    //Subscribe takes an event name from another particle (in this case:"heyimdry49ers") and searches for that event name in the cloud.
    //It then uses the myHandler function to obtain any data that is contained within the event.
    Particle.subscribe("heyimdry49ers", myHandler); //When recreating this, change the name in the quotations for an unique event name.
}

void loop() {
//N/A

}



void myHandler(const char *event, const char *data)
{
    //The data from "heyimdry49ers" is one of two states "dry" or "wet" (see other program)
    
    //strcmp compares the data to a string and returns 0 if they are the same.
    
    //The event "MotorControls49ers" contains the state of the motor, which is sent to the other Particle through the cloud and controls an LED on the other particle. 
    
    //Timer variables to be updated every time data is collected from the event.
    unsigned long CurrentTime = millis()/1000; //The current time (in seconds) since the program started
    unsigned long DeactivationTime = ActivationTime + OnDuration; //The time in seconds since the program started to "deactivate" the motor (turn the motor from the ON state to the OFF state)
    unsigned long NextActivationTime = DeactivationTime + waitDuration; //The value of the activation time
    unsigned long NextUpdateTime = NextActivationTime - 1; //The time since the program started to update ActivationTime from its old value to NextActivationTime
    
    //Control of the motor if the soil is dry
    if (strcmp(data,"dry")==0) {
            if (CurrentTime >= ActivationTime && CurrentTime < DeactivationTime){
                //If the current time is between the activation time and the deactivation time, turn the motor to the "ON" state and publish the current state
                Servo1.write(ONStatePos);
                Particle.publish("MotorControl49ers", "on"); 
            }
            else if (CurrentTime >= DeactivationTime && CurrentTime < NextUpdateTime){
                //If the current time is between the deactivation time and the next update time, turn the motor to the "OFF" state and publish the current state
                Servo1.write(OFFStatePos);
                Particle.publish("MotorControl49ers", "off");
            }
            else if(CurrentTime >= NextUpdateTime){
                //If the current time is greater than or equal to the next update time, publish the current state ("OFF"), and update the activation time to the next value.
                Particle.publish("MotorControl49ers", "off");
                ActivationTime = NextActivationTime;
            }
            //Else (if the current time is less than activation time), do nothing
            else{}
        }
    //If the soil is wet, turn the motor to the "OFF" state and publish the current state
    else if (strcmp(data,"wet")==0) {
            Servo1.write(OFFStatePos);
            Particle.publish("MotorControl49ers", "off");
            ActivationTime = CurrentTime + delayActivate;
      }
    //No other data states are published by the event, so there is nothing else to check. If something else does occur, do nothing.
    else {}
    
}