Arduino Countdown Timer

A 60-second timer (adjustable) countdown clock.

Jan 26, 2019

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89067 views

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20 respects

smart appliances

clocks

timer

Components and supplies

Jumper wires (generic)

SparkFun 7-Segment Serial Display - Red

Breadboard (generic)

Arduino Mega 2560

USB-A to Mini-USB Cable

Apps and platforms

Arduino IDE

Project description

Code

The code

arduino

Use this code to run your 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}

//7 segement pin number - 7 segement light - arduino pin number

//pin  11 - A = 12
//pin 7 - B = 10
//pin 4 - C = 8
//pin 2 - D = 7
//pin 1  - E = 6
//pin 10 - F = 11
//pin 5 - G = 9

//pin 3 is decimal

/*
12  11  10  9 8 7
|   |   |  | | | 
    A
   ---
F |   | B
  | G |
   ---
E |   | C
  |   |
   ---  . dec
    D
| | | | | |
1 2 3  4 5 6
*/

//pin 12 - first digit = 1
//pin 9 - second digit = 2 
//pin  8 - third digit = 3
//pin 6 fourth digit = 4

const int a = 12;
const  int b = 10;
const int c = 8;
const int d = 7;
const int e = 6;
const  int f = 11;
const int g = 9;
int p = 0;

int startStopReset = 13; 

const  int d1 =1;
const int d2 =2;
const int d3 =3;
const int d4 =4;

long  n = 60000; //start time -> CAN CHANGE TO WHATEVER TIME YOU WANT
int x = 100;  
int del = 55; //delay value
 
void setup()
{
  pinMode(d1, OUTPUT);
  pinMode(d2, OUTPUT);
  pinMode(d3, OUTPUT);
  pinMode(d4, OUTPUT);
  pinMode(a,  OUTPUT);
  pinMode(b, OUTPUT);
  pinMode(c, OUTPUT);
  pinMode(d, OUTPUT);
  pinMode(e, OUTPUT);
  pinMode(f, OUTPUT);
  pinMode(g, OUTPUT);
  pinMode(p,  OUTPUT);
  pinMode(startStopReset, INPUT); 
  digitalWrite(startStopReset,  HIGH); 
}
 
void loop()
{
  digitalWrite (p, HIGH);

  clearLEDs();
  pickDigit(1);
  pickNumber((n/x/1000)%10);
  delayMicroseconds(del);
  
  clearLEDs();
  pickDigit(2);
  pickNumber((n/x/100)%10);
  delayMicroseconds(del);
  
  clearLEDs();
  pickDigit(3);
  dispDec(3);
  pickNumber((n/x/10)%10);
  delayMicroseconds(del);
 
  clearLEDs();
  pickDigit(4);
  pickNumber(n/x%10);
  delayMicroseconds(del);
 
  n--; //'n++' for stopwatch
 
  if (digitalRead(13)  == LOW)
  {
    n = 60000; //re-start time -> CHANGE TO WHATEVER TIME YOU  ORIGONALLY SET (start time)
  }
}
 
void pickDigit(int x) //changes  digit
{
  digitalWrite(d1, HIGH);
  digitalWrite(d2, HIGH);
  digitalWrite(d3,  HIGH);
  digitalWrite(d4, HIGH);
 
  switch(x)
  {
  case 1: 
    digitalWrite(d1, LOW); 
    break;
  case 2: 
    digitalWrite(d2,  LOW); 
    break;
  case 3: 
    digitalWrite(d3, LOW);
    digitalWrite(p,  HIGH); //new 
    break;
  default: 
    digitalWrite(d4, LOW); 
    break;
  }
}
 
void pickNumber(int x) //changes value of number
{
  switch(x)
  {
  default: 
    zero(); 
    break;
  case 1: 
    one(); 
    break;
  case 2: 
    two(); 
    break;
  case 3: 
    three();  
    break;
  case 4: 
    four(); 
    break;
  case 5: 
    five();  
    break;
  case 6: 
    six(); 
    break;
  case 7: 
    seven();  
    break;
  case 8: 
    eight(); 
    break;
  case 9: 
    nine();  
    break;
  }
}
 
void dispDec(int x)
{
  digitalWrite(p,  LOW);
}
 
void clearLEDs()
{
  digitalWrite(a, LOW);
  digitalWrite(b,  LOW);
  digitalWrite(c, LOW);
  digitalWrite(d, LOW);
  digitalWrite(e,  LOW);
  digitalWrite(f, LOW);
  digitalWrite(g, LOW);
  digitalWrite(p,  LOW);
}
 
void zero()
{
  digitalWrite(a, HIGH);
  digitalWrite(b,  HIGH);
  digitalWrite(c, HIGH);
  digitalWrite(d, HIGH);
  digitalWrite(e,  HIGH);
  digitalWrite(f, HIGH);
  digitalWrite(g, LOW);
}
 
void  one()
{
  digitalWrite(a, LOW);
  digitalWrite(b, HIGH);
  digitalWrite(c,  HIGH);
  digitalWrite(d, LOW);
  digitalWrite(e, LOW);
  digitalWrite(f,  LOW);
  digitalWrite(g, LOW);
}
 
void two()
{
  digitalWrite(a,  HIGH);
  digitalWrite(b, HIGH);
  digitalWrite(c, LOW);
  digitalWrite(d,  HIGH);
  digitalWrite(e, HIGH);
  digitalWrite(f, LOW);
  digitalWrite(g,  HIGH);
}
 
void three()
{
  digitalWrite(a, HIGH);
  digitalWrite(b,  HIGH);
  digitalWrite(c, HIGH);
  digitalWrite(d, HIGH);
  digitalWrite(e,  LOW);
  digitalWrite(f, LOW);
  digitalWrite(g, HIGH);
}
 
void four()
{
  digitalWrite(a, LOW);
  digitalWrite(b, HIGH);
  digitalWrite(c, HIGH);
  digitalWrite(d, LOW);
  digitalWrite(e, LOW);
  digitalWrite(f, HIGH);
  digitalWrite(g, HIGH);
}
 
void five()
{
  digitalWrite(a, HIGH);
  digitalWrite(b, LOW);
  digitalWrite(c, HIGH);
  digitalWrite(d, HIGH);
  digitalWrite(e, LOW);
  digitalWrite(f, HIGH);
  digitalWrite(g, HIGH);
}
  
void six()
{
  digitalWrite(a, HIGH);
  digitalWrite(b, LOW);
  digitalWrite(c,  HIGH);
  digitalWrite(d, HIGH);
  digitalWrite(e, HIGH);
  digitalWrite(f,  HIGH);
  digitalWrite(g, HIGH);
}
 
void seven()
{
  digitalWrite(a,  HIGH);
  digitalWrite(b, HIGH);
  digitalWrite(c, HIGH);
  digitalWrite(d,  LOW);
  digitalWrite(e, LOW);
  digitalWrite(f, LOW);
  digitalWrite(g,  LOW);
}
 
void eight()
{
  digitalWrite(a, HIGH);
  digitalWrite(b,  HIGH);
  digitalWrite(c, HIGH);
  digitalWrite(d, HIGH);
  digitalWrite(e,  HIGH);
  digitalWrite(f, HIGH);
  digitalWrite(g, HIGH);
}
 
void  nine()
{
  digitalWrite(a, HIGH);
  digitalWrite(b, HIGH);
  digitalWrite(c,  HIGH);
  digitalWrite(d, HIGH);
  digitalWrite(e, LOW);
  digitalWrite(f,  HIGH);
  digitalWrite(g, HIGH);
}

Downloadable files

The schematic

Use this connection diagram to connect your 4 digit display to your arduino

The schematic

Use this connection diagram to connect your 4 digit display to your arduino

The schematic

Comments

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carlosca001

2 years ago

HI thanks for the info

Anonymous user

2 years ago

maybe I don't understand something, but why my timer stopped 8888 I tried to mess around with the code, but nothing happened, please tell me

ebolson

2 years ago

same thing happened to me, did you have any luck?

Anonymous user

2 years ago

Can I make this loop (As in auto-reset and restart) Thanks

helpmefirstineedhelp

2 years ago

hi I was wondering if you can use a arduino uno in this project?

lplnmdh

2 years ago

can you fix this for me plz i want this for watering system unsigned long Levent = 10000 ; unsigned long Pevent = 10000 ; static unsigned long preTL = 0 ; static unsigned long preTP = 0 ; int MAXL = 5000; void setup() { Serial.begin(9600); } void loop() { unsigned long currenttime = millis(); if (currenttime - preTL >= Levent) { // do Thing A } else if (currenttime - perTL >= MAXL) { // do Thing B } else { // do Thing C } if(currenttime - preTP >= Pevent) { //relay turn on cods delay (100000); //relay turn off cods delay (500); preTP = currenttime ; } }

sdeornellas

2 years ago

Sorry, very new over here. In the diagram/schematic there are no indications for what pins to connect to on the spark fun timer board. Additionally, in the mage for the project itself it looks like just the display is used, not the board it ships mounted to. Am I missing something obvious? how do I know what leads to connect to the Arduino?

siebeettema

2 years ago

can I set the timer to hours or minutes instead of seconds ???

Anonymous user

3 years ago

maybe I don't understand something, but why my timer stopped 8888 I tried to mess around with the code, but nothing happened, please tell me

sdeornellas

3 years ago

Anonymous user

4 years ago

Can I make this loop (As in auto-reset and restart) Thanks

ebolson

2 years ago

try an if statement that if n=0 set n to start time

ebolson

4 years ago

If i adjusted the pick number in lines 78,83,89,94 would it be possible to have the display show tenths and hundreths of a second? also, where does pin 0 connect? p is used to clear the display but you dont say where it connects.

Anonymous user

2 years ago

I changed the 100 to 10 on line 51 and it gave me hundredth

Anonymous user

2 years ago

maybe I don't understand something, but why my timer stopped 8888 I tried to mess around with the code, but nothing happened, please tell me

lplnmdh

5 years ago

siebeettema

5 years ago

can I set the timer to hours or minutes instead of seconds ???

tylerpeppy

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16 Projects

Intro

Components and supplies

Apps and platforms

Project description

Code

Downloadable files