Plant watering system
A simple circuit and software that checks every 12 hours if there is water is the pot tray and if it’s not it starts a pump for 6 seconds.
The water sensor is a 1 MΩ resistor.
What’s left to do:
- Power it from a battery (that’s why I’ve included the LowPower.h library)
- Build a box
The code:
/* Copyright © 2018 Razvan Murariu <razwww@gmail.com> This program is free software. It comes without any warranty, to the extent permitted by applicable law. You can redistribute it and/or modify it under the terms of the Do What The Fuck You Want To Public License, Version 2, as published by Sam Hocevar. See the COPYING file for more details. The circuit: Water pump: D7 Sensor (1 MO resistor): A0 */ #include <LowPower.h> #define sensorPin A0 byte pumpPin=4; int tempo=6000; //watering time int i=0; //counter int readSensor() { byte readCount = 0; int sensorValueTotal = 0; int sensorValueAveraged = 0; digitalWrite(sensorPin,HIGH); // to avoid electrocorrosion we set it to high only during measuring while (readCount < 5) { int sensorValue = analogRead(sensorPin); // Serial.println(sensorValue); sensorValueTotal += sensorValue; readCount++; delay(10); } sensorValueAveraged = sensorValueTotal / 5; digitalWrite(sensorPin,LOW); // Serial.println(sensorValueAveraged); return (sensorValueAveraged); } void setup() { Serial.begin(9600); pinMode(pumpPin,OUTPUT); pinMode(sensorPin,INPUT); pinMode(13,OUTPUT); digitalWrite(13,LOW); //turn off led digitalWrite(pumpPin,LOW); //turn off pump } void loop() { if( i==0 && readSensor()>900 ) { // dry=982 digitalWrite(pumpPin,HIGH); delay(tempo); digitalWrite(pumpPin,LOW); // Serial.println("pompa"); } i++; // Enter power down state for X s with ADC and BOD module disabled LowPower.powerDown(SLEEP_8S, ADC_OFF, BOD_OFF); if( i==5400 ) { // 10800 = once per day i=0; // reset i } }The most recent version of the code is found on GitHub