Hi,
Is there any function to read the time duration of Relay when its HIGH?
For example :
- Relay is HIGH for 30 second.
- The value of the 30 second time is entered into variable "relaytime"
#include <Wire.h>
#include <LiquidCrystal_I2C.h>
#include <Servo.h>
LiquidCrystal_I2C lcd(0x27, 16, 2);
#define trig 5
#define echo 4
Servo servo;
const int sensor = 3;
const int Relay = 6;
int state;
int value;
long duration;
int distance;
void setup() {
lcd.begin();
lcd.print("Wash your hands");b
lcd.setCursor(0,1);
lcd.print("before you enter");
servo.attach(9); // The servo motor is connected to D9
pinMode(trig, OUTPUT); // Set the trigger pin as OUTPUT
pinMode(echo, INPUT); // Set the echo pin as INPUT
pinMode(sensor, INPUT); // Configure the pin of the IR sensor as INPUT
pinMode(Relay, OUTPUT); // Configure the pin of the relay module as OUTPUT
Serial.begin(9600); // Set baud rate as 9600
}
void loop() {
digitalWrite(trig, LOW);
delayMicroseconds(5);
digitalWrite(trig, HIGH); // Set the trigger pin HIGH to send the ultrasonic wave (pulse)
delayMicroseconds(10);
digitalWrite(trig, LOW);
value=digitalRead(sensor); // Read the digital signal sent by the IR sensor and store it in the 'value' variable
duration = pulseIn(echo, HIGH); // Calculate time taken (in microseconds) for the pulse emitted by the trigger pin to reach the echo pin.
distance = (duration/2) * (331.3/10000); // Calculate the distance from the sensor to the obstacle in cm, using the speed of sound in air(m/s) and the time taken (stored in duration variable)
Serial.println(distance);
if(distance>1 && distance<15){ // If you place your hands within 15 cm
lcd.clear();
lcd.setCursor(1,0);
lcd.print("Hands detected");
lcd.setCursor(0,1);
lcd.print("Wash hands - 20s");
digitalWrite(Relay, HIGH); //Turns on the submersible water pump or solenoid water valve
state=1; // Assign state variable to 1
delay(1000); // Delay period of 1 second must be used to prevent clicking of the relay module
lcd.clear();
lcd.print("You are safe now");
}else{
digitalWrite(Relay, LOW); //Turns off the submersible water pump or solenoid water valve
}
if((state==1)&&(value==LOW)){ // If you place your hands in front of the IR sensor after washing your hands
lcd.clear();
lcd.setCursor(1,0);
lcd.print("You may go in");
lcd.setCursor(1,1);
lcd.print("10 seconds left");
servo.write(90);
delay(10000); // The door will be opened for 10 seconds
servo.write(0);
lcd.clear();
lcd.print("Wash your hands");
lcd.setCursor(0,1);
lcd.print("before you enter");
state=0;
} else if((state==0)&&(value==LOW)){ // If you do not wash your hands before you enter
lcd.clear();
lcd.print("Wash your hands");
lcd.setCursor(0,1);
lcd.print("to grant access");
}
}
.