Tempeh Incubator

1#include <Wire.h> //  I2C/TWI comunication library
2#include "rgb_lcd.h"  //  "Grove" lcd library
3#include <dht.h>  //  sensor library using lib from  https://www.ardumotive.com/how-to-use-dht-22-sensor-en.html
4
5
6
7#define  DHTTYPE DHT22 //  defines sensor type - DHT 22 (AM2302)
8
9
10
11//  replacements
12dht  DHT;
13rgb_lcd lcd;
14
15
16
17//  pins set up
18const int DHT22_PIN = 2;  //  set up DHT22
19const int Up_buttonPin   = 12;  //  set up the pushbutton  (+)
20const int Down_buttonPin = 13;  //  set up the pushbutton (-)
21const int  Bulb_ON = 3;  //  set up the ON led (green)
22const int Bulb_OFF = 5; //  set up  the OFF led (red)
23const int Relay = 4;  //  set up the relay
24
25
26
27//  variables
28int Temp_limit = 30;  //  counter for the number of button presses
29int  up_buttonState = 0; //  current state of the up button
30int up_lastButtonState  = 0; //  previous state of the up button
31int down_buttonState = 0; //  current  state of the up button
32int down_lastButtonState = 0; //  previous state of the  up button
33int i;  //  loop counter
34int state_change_counter = 0; //  num of  state change during the procces
35float hum;  //  stores humidity value
36float  temp; //  stores temperature value
37bool bPress = false;  //  helps us to detect  when the state of buttons has changed
38bool state_helper = true; //  helps to  determine num of state change during the procces
39
40
41
42void setup ()
43{
44  Serial.begin (9600);
45  //  set up I/O
46  pinMode (Up_buttonPin , INPUT_PULLUP);
47  pinMode (Down_buttonPin , INPUT_PULLUP);
48  pinMode (Relay, OUTPUT);
49  pinMode  (Bulb_OFF, OUTPUT);
50  pinMode (Bulb_ON, OUTPUT);
51  lcd.begin (16, 2);  //  set up the LCD's number of columns and rows:
52  PrintTLimit ();
53  delay (2000);
54  PrintTandH ();
55  digitalWrite (Relay, LOW);
56  digitalWrite (Bulb_OFF, LOW);
57  digitalWrite (Bulb_ON, LOW);
58}
59
60
61
62void loop ()
63{
64  if (temp  <= Temp_limit - 0.5)
65  {
66    while (temp < Temp_limit + 0.5)
67    {
68      Relay_ON ();
69      if (state_helper)   // counts relay state changes
70      {
71        state_change_counter ++;
72        state_helper = false;
73      }
74      checkUp ();
75      checkDown ();
76      if (temp >= Temp_limit  + 0.5)
77        break;
78      if (bPress)
79        Delay_screen ();
80      PrintTandH  ();
81    }
82  }
83  else
84  {
85    Relay_OFF ();
86    state_helper =  true;
87    checkUp ();
88    checkDown ();
89    if (bPress)
90      Delay_screen  ();
91    PrintTandH ();
92  }
93}
94
95
96
97// checks UP button
98void  checkUp ()
99{
100  up_buttonState = digitalRead (Up_buttonPin);
101  // compare  the buttonState to its previous state
102  if (up_buttonState != up_lastButtonState)  
103  {
104    if (up_buttonState == LOW)  // if the current state is LOW then the  button went from on to off:
105    {
106      bPress = true;
107      Temp_limit  ++;
108      i = 0;
109    } 
110    delay (50);    // delay to avoid bouncing
111  }
112  up_lastButtonState = up_buttonState;    // save the current state as the  last state, for next time through the loop
113}
114
115
116
117// checks DOWN button
118void  checkDown ()
119{
120  down_buttonState = digitalRead (Down_buttonPin);
121  if  (down_buttonState != down_lastButtonState)   // compares the buttonState to its  previous state
122  {
123    // if the state has changed, increment the counter
124    if (down_buttonState == LOW)  // if the current state is LOW then the button  went from on to off:
125    {
126      bPress = true;
127      Temp_limit --;
128      i = 0;
129    } 
130    delay (50);   // delay to avoid bouncing
131  }
132  down_lastButtonState = down_buttonState;  // save the current state as the last  state, for next time through the loop
133}
134
135
136
137// turns on the relay
138void  Relay_ON ()
139{
140  // configuration for Relay and leds
141  digitalWrite (Bulb_OFF,  LOW);
142  digitalWrite (Relay, HIGH);
143  analogWrite (Bulb_ON, 10); // reduces  power supply to decrease the led's brightness
144}
145
146
147
148//  turns off  the relay
149void Relay_OFF ()
150{
151  // configuration for Relay and leds
152  analogWrite (Bulb_OFF, 40); // reduces power supply to decrease the led's brightness
153  digitalWrite (Relay, LOW);
154  digitalWrite (Bulb_ON, LOW);   
155}
156
157
158
159//  captures temperature limit screen for couple seconds
160void Delay_screen ()
161{
162  Save_Mode ();
163  for (i = 0; i < 10; ++i) // delays the temperature limit print  on LCD
164  {
165    checkUp ();
166    checkDown ();
167    PrintTLimit ();
168  }
169  bPress = false;
170  PrintTandH ();
171}
172
173
174
175//  configuration  for Relay and leds, saves the system from overheating while pushing buttons
176void  Save_Mode ()
177{
178    digitalWrite (Relay, LOW);
179    analogWrite (Bulb_OFF,  40);
180    digitalWrite (Bulb_ON, LOW);
181    lcd.clear ();
182}
183
184
185
186//  prints tempearure limit screen
187void PrintTLimit ()
188{
189  lcd.clear ();
190  lcd.setCursor (0, 0);
191  lcd.print ("Limit (T)");
192  lcd.setCursor (2,1);
193  lcd.print (Temp_limit);
194  lcd.setCursor (6,1);
195  lcd.print ("O/I=");
196  lcd.setCursor (10,1);
197  lcd.print (state_change_counter);
198  delay (100);  // delay to avoid LCD bouncing
199}
200
201
202
203//  prints the main screen  with temperature and humidity observation
204void PrintTandH ()
205{
206  lcd.clear  ();
207  int chk = DHT.read22 (DHT22_PIN);
208  hum = DHT.humidity;     // read  humidity data and store it to variable hum
209  temp = DHT.temperature; // read  temerature data and store it to variable temp
210  lcd.setCursor (0, 0);  // set  the cursor to column 0, line 0
211  lcd.print ("Humidity(%):"); // print text
212  lcd.print (hum); //  print humidity value
213  lcd.setCursor (0, 1);  // set the  cursor to column 0, line 1
214  lcd.print ("Temperature:"); // print text
215  lcd.print (temp);  // print temperature value
216  delay (100);  // delay to avoid  LCD bouncing
217}
218