Making Arduino + Coin Sensor Project for Vending Machine

1boolean buttonPressed = false;
2int count = 0;
3int totalCount = 0;
4int  cents = 0;
5
6void setup() {
7  Serial.begin(19200);
8  attachInterrupt(digitalPinToInterrupt(2),  buttonCB, FALLING);
9  attachInterrupt(digitalPinToInterrupt(3), coinAcceptorCB,  FALLING);
10  pinMode(4, OUTPUT);
11}
12
13
14void buttonCB() {
15  Serial.println("Button  pressed");
16  buttonPressed = true;
17}
18
19void coinAcceptorCB() {
20  count  = count + 1;
21  cents = 10 * count;
22  Serial.print("Count = ");
23  Serial.println(count);
24  Serial.print(cents);
25  Serial.println(" cents received. ");
26
27}
28
29void  loop() {
30  if (buttonPressed) {
31    if (5 <= totalCount && totalCount < 10)  {
32//      DISPENSE WATER
33      digitalWrite(4, HIGH);
34      delay(5000);
35      digitalWrite(4, LOW);
36      buttonPressed = false;  
37//      SHOW RECEIPT
38      Serial.print("Total count: ");
39      Serial.println(totalCount);
40      totalCount = 0;
41    } else {
42      Serial.println("Insufficient. Minimum  is 50 Cents.");
43      buttonPressed = false;
44    }
45  }
46
47  delay(1000);
48  totalCount = totalCount + count;
49  count = 0;
50}