Automated Gardening Plant - Activity for Kids 1

1<p>//import the library to control LCD display, this library has been
2  added manually through ZIP file<br>#include 
3</p><p>//import library for DHT
4  sensor
5#include "dht.h"
6#define dht_apin A3 // Analog Pin sensor is connected
7  to</p><p>//create DHT object
8dht DHT;</p><p>// create LCD object
9LiquidCrystal_I2C
10  lcd(0x27,20,4);  // set the LCD address to 0x27 for a 16 chars and 2 line display</p><p>//declaration
11  of variable for buttond
12int ButtonOnePin = 10;  //pin for button 1
13int ButtonOneState
14  =0 ; //one variable to store current button state
15int ButtonOnePreviousState
16  = 0; //one variable to store previous button state
17int ButtonTwoPin = 9; // same
18  for button 2
19int ButtonTwoState =0 ;
20int ButtonTwoPreviousState = 0;</p><p>unsigned
21  long timeBeginDisplay=0;
22int timeDisplayPeriod = 6000; //period the 2nd and 3rd
23  screen are displayed
24int valToDisplay = 0; //variable to decide what information
25  is to be displayed</p><p>int airTemp; //variable to store air temperature measured
26  by DHT11 sensor
27int airHumidity; //variable to store air humidity measured by
28  DHT11 sensor</p><p>int LedPin =  13; </p><p>int waterPumpPin=7; // pin on which
29  is connected the relay that command water pump
30int sprayNum=0; //variable to
31  store number of spraying 
32int pumpOn =false; //variable used for spraying, it
33  stays ON during the spray timing</p><p>int MoistureHigh = 800; 
34int MoistureGood
35  = 710;
36int MoistureLow = 630; //threshold that should launch water spray of the
37  plant
38int valSoil ;  //variable to store value measured by moisture sensor
39int
40  soilPin = A0; // pin on wich is connected moisture sensor
41int soilPower = 12;</p><p>int
42  timePeriod = 1000; //variable to store timing in ms, period between each display
43  refresh, a clear is called each time display is called 
44int humMeasurePeriod=0;
45  
46unsigned long currentMillis; //variable to store current timing
47unsigned
48  long debutMillis=0; //variable used to store timing at the debut of a period
49int
50  timePumpPeriod = 3000; //timing for water spraying
51unsigned long timePumpDebut
52  = 0; //variable used to store timing value for the debut of a spraying period</p><p>int
53  gazPin = 1; //pin on which is connected gaz sensor
54int valGaz ; //variable on
55  which is stored gaz sensor value</p><p>int lightPin = 2; //pin on which is connected
56  the photoresistor
57int valLight ; //variable on which light value is stored</p><p>//function
58  to read moisture sensor value
59int readSoil()
60{</p><p>    digitalWrite(soilPower,
61  HIGH);//turn D7 "On"
62    delay(10);//wait 10 milliseconds 
63    valSoil =
64  analogRead(soilPin);//Read the SIG value form sensor 
65    digitalWrite(soilPower,
66  LOW);//turn D7 "Off"
67    return valSoil;//send current moisture value
68}</p><p>//function
69  called to refresh LCD screen, displaying wanted screen regarding value of variable
70  "valToDisplay" 
71int toDisplay(){</p><p>  lcd.clear(); //clear the screen to
72  remove character that might not be overwritten by new message
73  
74  if (valToDisplay==0){
75
76    lcd.setCursor(0,0); //to put cursor on 1rst character of 1rst line
77    lcd.print("Temp:");
78
79    lcd.setCursor(6,0);
80    lcd.print("Hum:");
81    lcd.setCursor(11,0);
82
83    lcd.print("Mois:");
84    lcd.setCursor(0,1); //to put cursor on 1rst character
85  of 2nd line
86    lcd.print(airTemp);
87    lcd.setCursor(2,1);
88    lcd.print((char)223);
89  //special character for temperature
90    lcd.print("C");
91    lcd.setCursor(6,1);
92  
93    lcd.print(airHumidity);
94    lcd.setCursor(8,1); 
95    lcd.print("%");
96
97    lcd.setCursor(11,1); 
98    lcd.print(valSoil); 
99  }
100  else if (valToDisplay==1
101  && (currentMillis-timeBeginDisplay)</p><p>  if((currentMillis-timeBeginDisplay)>timeDisplayPeriod){
102  //display original screen when display period is over
103    valToDisplay=0;
104
105    //we display in this IF condition the 1rst screen because before there was a
106  blank screen after the timing
107    lcd.setCursor(0,0); //to put cursor on 1rst
108  character of 1rst line
109    lcd.print("Temp:");
110    lcd.setCursor(6,0);
111
112    lcd.print("Hum:");
113    lcd.setCursor(11,0);
114    lcd.print("Mois:");
115
116    lcd.setCursor(0,1); //to put cursor on 1rst character of 2nd line
117    lcd.print(airTemp);
118
119    lcd.setCursor(2,1);
120    lcd.print((char)223); //special character for temperature
121
122    lcd.print("C");
123    lcd.setCursor(6,1);  
124    lcd.print(airHumidity);
125
126    lcd.setCursor(8,1); 
127    lcd.print("%");
128    lcd.setCursor(11,1); 
129
130    lcd.print(valSoil); 
131  }
132  
133}</p><p>int readTempHum (){</p><p>    DHT.read11(dht_apin);
134  //read value from DHT sensor</p><p>    airTemp = DHT.temperature; //store temperature
135  value from sensor
136    airHumidity = DHT.humidity; // store humidity value from
137  sensor
138    
139    //delay(3000);//Wait 3 seconds before accessing sensor again,
140  without timing, sensor measurement is faulty. we commented this delay because this
141  function isn't called often
142}</p><p>int waterPump(){</p><p>  //the condition
143  below to command or not the water pump
144  if (valSoil</p><p>  //once the waterpump
145  cycle is launched, this if condition will turn ON the pump on the third of the timePumpPeriod
146  defined, the other 2 third, the water pump will be turned OFF
147  if (currentMillis-timePumpDebut=timePumpPeriod
148  && pumpOn==true){
149      pumpOn=false; //once pump cycle is over, variable value
150  change to make water spraying dependant on moisture value again
151      sprayNum++;
152  //add +1 to the number of spraying performed
153  }
154}</p><p>int waterTankAlarm(){
155
156  if (sprayNum>10){ //when number of spraying is above limit, turn on led to warn
157  user
158    digitalWrite(LedPin,HIGH);
159  }
160  else {
161    digitalWrite(LedPin,LOW);
162
163  }
164}</p><p>void setup() { 
165  // put your setup code here, to run once:
166
167  Serial.begin(9600);
168  //defining wich pin are IN or OUT
169  pinMode(LedPin,
170  OUTPUT);      
171  pinMode(ButtonOnePin, INPUT); 
172  pinMode(ButtonTwoPin, INPUT);
173  
174  pinMode(waterPumpPin, OUTPUT); </p><p>  // initialize the lcd
175  lcd.init();
176                       
177  lcd.backlight();
178  lcd.setCursor(0,0); 
179  lcd.print("Waking
180  up");</p><p>  //ready first temperature and humidity from DHT sensor to store value
181  (since this function isn't called often)
182  readTempHum();
183  
184  delay(2000);
185
186  lcd.clear();</p><p>  
187}</p><p>void loop() {</p><p>  //reading of sensor value,
188  not DHT due to the delay needed to its measurement
189  readSoil();
190  valGaz
191  = analogRead(gazPin);
192  valLight = analogRead(lightPin);</p><p>  currentMillis=millis();
193  //measurement of current time</p><p>  //small function to avoid button rebound,
194  when pressing once on the button, arduino reads only one pressing...
195  ButtonOneState=digitalRead(ButtonOnePin);
196  //reading of button value
197  if (ButtonOneState !=ButtonOnePreviousState){ //comparing
198  with previous state
199    if (ButtonOneState == HIGH){ //if previous state was
200  0 and current is 1, then take button pressing in account
201      delay(200);
202
203      valToDisplay=1;
204      timeBeginDisplay=currentMillis;
205    }
206    ButtonOnePreviousState=ButtonOneState;
207
208  }
209  //same function for button 2 as button 1
210  ButtonTwoState=digitalRead(ButtonTwoPin);
211
212  if (ButtonTwoState !=ButtonTwoPreviousState){
213    if (ButtonTwoState == HIGH){
214
215      delay(200);
216      valToDisplay=2; //particular value for "valToDisplay"
217
218      timeBeginDisplay=currentMillis;
219    }
220    ButtonTwoPreviousState=ButtonTwoState;
221
222  }
223  
224  waterPump(); //calling for water pump function which launch spray
225  cycle if needed</p><p>  waterTankAlarm(); //calling function to warn user about
226  water tank level</p><p>  //small condition for screen refreshing and measurement
227  of DHT sensor
228  if (currentMillis-debutMillis>timePeriod){ //end of a period
229
230    debutMillis=currentMillis; //define the begining of a new period
231    toDisplay();
232  //refresh of the screen regarding "valToDisplay" value
233    humMeasurePeriod++;
234  //DHT sensor values are measured every 20 times the screens is refreshed
235    if
236  (humMeasurePeriod>20){ //go to measure DHT values
237          readTempHum();
238
239          humMeasurePeriod=0;
240    }</p><p>  } </p><p>}</p>