How to Drive a 7 Segment Display with HCF4511

1/*
2  Example of how to drive a seven segment display using HCF4511  or similar
3
4 This sketch drive the display in order to show a number from  0 to 9 everytime a button connected to A0 is pressed.
5 
6*/
7
8//Declaration  of Arduino pins used as HCF4511 inputs
9const int A=2;
10const int B=3;
11const  int C=4;
12const int D=5;
13
14void setup() {
15  pinMode(A0, INPUT);
16  pinMode(A,  OUTPUT); //LSB
17  pinMode(B, OUTPUT);
18  pinMode(C, OUTPUT);
19  pinMode(D,  OUTPUT); //MSB
20
21}
22
23int count = 0; //the variable used to show the number
24
25void  loop() {
26  if (digitalRead(A0) == LOW) //if button is pressed
27    {
28    count++;  
29    delay(200); //the delay prevent from button bouncing
30    if (count ==  10) //we want to count from 0 to 9!
31      count = 0;
32    to_BCD(); //convert  to binary
33    }
34   
35  if (count == 10)
36    count = 0;
37  
38}
39
40void  to_BCD()
41{
42    if (count == 0) //write 0000
43	{
44      digitalWrite(A,  LOW);
45      digitalWrite(B, LOW);
46      digitalWrite(C, LOW);
47      digitalWrite(D,  LOW);
48    }
49    
50    if (count == 1) //write 0001
51	{
52      digitalWrite(A,  HIGH);
53      digitalWrite(B, LOW);
54      digitalWrite(C, LOW);
55      digitalWrite(D,  LOW);
56    }
57    
58    if (count == 2) //write 0010
59	{
60      digitalWrite(A,  LOW);
61      digitalWrite(B, HIGH);
62      digitalWrite(C, LOW);
63      digitalWrite(D,  LOW);
64    }
65    
66    if (count == 3) //write 0011
67	{
68      digitalWrite(A,  HIGH);
69      digitalWrite(B, HIGH);
70      digitalWrite(C, LOW);
71      digitalWrite(D,  LOW);
72    }
73    
74    if (count == 4) //write 0100
75	{
76      digitalWrite(A,  LOW);
77      digitalWrite(B, LOW);
78      digitalWrite(C, HIGH);
79      digitalWrite(D,  LOW);
80    }
81    
82    if (count == 5) //write 0101
83	{
84      digitalWrite(A,  HIGH);
85      digitalWrite(B, LOW);
86      digitalWrite(C, HIGH);
87      digitalWrite(D,  LOW);
88    }
89    
90    if (count == 6) //write 0110
91	{
92      digitalWrite(A,  LOW);
93      digitalWrite(B, HIGH);
94      digitalWrite(C, HIGH);
95      digitalWrite(D,  LOW);
96    }
97    
98    if (count == 7) //write 0111
99	{
100      digitalWrite(A,  HIGH);
101      digitalWrite(B, HIGH);
102      digitalWrite(C, HIGH);
103      digitalWrite(D,  LOW);
104    }
105    
106    if (count == 8) //write 1000
107	{
108      digitalWrite(A,  LOW);
109      digitalWrite(B, LOW);
110      digitalWrite(C, LOW);
111      digitalWrite(D,  HIGH);
112    }
113    
114    if (count == 9) //write 1001
115	{
116      digitalWrite(A,  HIGH);
117      digitalWrite(B, LOW);
118      digitalWrite(C, LOW);
119      digitalWrite(D,  HIGH);
120    } 
121}
122