Arduino Countdown Timer

1//7 segement pin number - 7 segement light - arduino pin number
2
3//pin  11 - A = 12
4//pin 7 - B = 10
5//pin 4 - C = 8
6//pin 2 - D = 7
7//pin 1  - E = 6
8//pin 10 - F = 11
9//pin 5 - G = 9
10
11//pin 3 is decimal
12
13/*
1412  11  10  9 8 7
15|   |   |  | | | 
16    A
17   ---
18F |   | B
19  | G |
20   ---
21E |   | C
22  |   |
23   ---  . dec
24    D
25| | | | | |
261 2 3  4 5 6
27*/
28
29//pin 12 - first digit = 1
30//pin 9 - second digit = 2 
31//pin  8 - third digit = 3
32//pin 6 fourth digit = 4
33
34const int a = 12;
35const  int b = 10;
36const int c = 8;
37const int d = 7;
38const int e = 6;
39const  int f = 11;
40const int g = 9;
41int p = 0;
42
43int startStopReset = 13; 
44
45const  int d1 =1;
46const int d2 =2;
47const int d3 =3;
48const int d4 =4;
49
50long  n = 60000; //start time -> CAN CHANGE TO WHATEVER TIME YOU WANT
51int x = 100;  
52int del = 55; //delay value
53 
54void setup()
55{
56  pinMode(d1, OUTPUT);
57  pinMode(d2, OUTPUT);
58  pinMode(d3, OUTPUT);
59  pinMode(d4, OUTPUT);
60  pinMode(a,  OUTPUT);
61  pinMode(b, OUTPUT);
62  pinMode(c, OUTPUT);
63  pinMode(d, OUTPUT);
64  pinMode(e, OUTPUT);
65  pinMode(f, OUTPUT);
66  pinMode(g, OUTPUT);
67  pinMode(p,  OUTPUT);
68  pinMode(startStopReset, INPUT); 
69  digitalWrite(startStopReset,  HIGH); 
70}
71 
72void loop()
73{
74  digitalWrite (p, HIGH);
75
76  clearLEDs();
77  pickDigit(1);
78  pickNumber((n/x/1000)%10);
79  delayMicroseconds(del);
80  
81  clearLEDs();
82  pickDigit(2);
83  pickNumber((n/x/100)%10);
84  delayMicroseconds(del);
85  
86  clearLEDs();
87  pickDigit(3);
88  dispDec(3);
89  pickNumber((n/x/10)%10);
90  delayMicroseconds(del);
91 
92  clearLEDs();
93  pickDigit(4);
94  pickNumber(n/x%10);
95  delayMicroseconds(del);
96 
97  n--; //'n++' for stopwatch
98 
99  if (digitalRead(13)  == LOW)
100  {
101    n = 60000; //re-start time -> CHANGE TO WHATEVER TIME YOU  ORIGONALLY SET (start time)
102  }
103}
104 
105void pickDigit(int x) //changes  digit
106{
107  digitalWrite(d1, HIGH);
108  digitalWrite(d2, HIGH);
109  digitalWrite(d3,  HIGH);
110  digitalWrite(d4, HIGH);
111 
112  switch(x)
113  {
114  case 1: 
115    digitalWrite(d1, LOW); 
116    break;
117  case 2: 
118    digitalWrite(d2,  LOW); 
119    break;
120  case 3: 
121    digitalWrite(d3, LOW);
122    digitalWrite(p,  HIGH); //new 
123    break;
124  default: 
125    digitalWrite(d4, LOW); 
126    break;
127  }
128}
129 
130void pickNumber(int x) //changes value of number
131{
132  switch(x)
133  {
134  default: 
135    zero(); 
136    break;
137  case 1: 
138    one(); 
139    break;
140  case 2: 
141    two(); 
142    break;
143  case 3: 
144    three();  
145    break;
146  case 4: 
147    four(); 
148    break;
149  case 5: 
150    five();  
151    break;
152  case 6: 
153    six(); 
154    break;
155  case 7: 
156    seven();  
157    break;
158  case 8: 
159    eight(); 
160    break;
161  case 9: 
162    nine();  
163    break;
164  }
165}
166 
167void dispDec(int x)
168{
169  digitalWrite(p,  LOW);
170}
171 
172void clearLEDs()
173{
174  digitalWrite(a, LOW);
175  digitalWrite(b,  LOW);
176  digitalWrite(c, LOW);
177  digitalWrite(d, LOW);
178  digitalWrite(e,  LOW);
179  digitalWrite(f, LOW);
180  digitalWrite(g, LOW);
181  digitalWrite(p,  LOW);
182}
183 
184void zero()
185{
186  digitalWrite(a, HIGH);
187  digitalWrite(b,  HIGH);
188  digitalWrite(c, HIGH);
189  digitalWrite(d, HIGH);
190  digitalWrite(e,  HIGH);
191  digitalWrite(f, HIGH);
192  digitalWrite(g, LOW);
193}
194 
195void  one()
196{
197  digitalWrite(a, LOW);
198  digitalWrite(b, HIGH);
199  digitalWrite(c,  HIGH);
200  digitalWrite(d, LOW);
201  digitalWrite(e, LOW);
202  digitalWrite(f,  LOW);
203  digitalWrite(g, LOW);
204}
205 
206void two()
207{
208  digitalWrite(a,  HIGH);
209  digitalWrite(b, HIGH);
210  digitalWrite(c, LOW);
211  digitalWrite(d,  HIGH);
212  digitalWrite(e, HIGH);
213  digitalWrite(f, LOW);
214  digitalWrite(g,  HIGH);
215}
216 
217void three()
218{
219  digitalWrite(a, HIGH);
220  digitalWrite(b,  HIGH);
221  digitalWrite(c, HIGH);
222  digitalWrite(d, HIGH);
223  digitalWrite(e,  LOW);
224  digitalWrite(f, LOW);
225  digitalWrite(g, HIGH);
226}
227 
228void four()
229{
230  digitalWrite(a, LOW);
231  digitalWrite(b, HIGH);
232  digitalWrite(c, HIGH);
233  digitalWrite(d, LOW);
234  digitalWrite(e, LOW);
235  digitalWrite(f, HIGH);
236  digitalWrite(g, HIGH);
237}
238 
239void five()
240{
241  digitalWrite(a, HIGH);
242  digitalWrite(b, LOW);
243  digitalWrite(c, HIGH);
244  digitalWrite(d, HIGH);
245  digitalWrite(e, LOW);
246  digitalWrite(f, HIGH);
247  digitalWrite(g, HIGH);
248}
249  
250void six()
251{
252  digitalWrite(a, HIGH);
253  digitalWrite(b, LOW);
254  digitalWrite(c,  HIGH);
255  digitalWrite(d, HIGH);
256  digitalWrite(e, HIGH);
257  digitalWrite(f,  HIGH);
258  digitalWrite(g, HIGH);
259}
260 
261void seven()
262{
263  digitalWrite(a,  HIGH);
264  digitalWrite(b, HIGH);
265  digitalWrite(c, HIGH);
266  digitalWrite(d,  LOW);
267  digitalWrite(e, LOW);
268  digitalWrite(f, LOW);
269  digitalWrite(g,  LOW);
270}
271 
272void eight()
273{
274  digitalWrite(a, HIGH);
275  digitalWrite(b,  HIGH);
276  digitalWrite(c, HIGH);
277  digitalWrite(d, HIGH);
278  digitalWrite(e,  HIGH);
279  digitalWrite(f, HIGH);
280  digitalWrite(g, HIGH);
281}
282 
283void  nine()
284{
285  digitalWrite(a, HIGH);
286  digitalWrite(b, HIGH);
287  digitalWrite(c,  HIGH);
288  digitalWrite(d, HIGH);
289  digitalWrite(e, LOW);
290  digitalWrite(f,  HIGH);
291  digitalWrite(g, HIGH);
292}