4/4 Metronome With LEDs and Sound

1//IMPORTANT NOTE: This code only reflects the Tinkercad simulator setup. If using the Arduino Modulino components (buzzer and knob) listed in the components section of this project page, code for those pieces would look slightly different. Adjust as needed 
2
3#include <LiquidCrystal.h>
4
5//pin variables
6const int SPEAKER = 13;
7const int YELLOW_LED = 12;
8const int BLUE_LED1 = 11;
9const int BLUE_LED2  = 10;
10const int BLUE_LED3 = 9;
11const int DIAL = A0;
12//lcd pin variables
13const int RS = 2;
14const int E = 4;
15const int DB4 = 5;
16const int DB5 = 6;
17const int DB6 = 7;
18const int DB7 = 8;
19
20//instantiate lcd object
21LiquidCrystal lcd(RS, E, DB4, DB5, DB6, DB7);
22
23//for counting beats in the time signature
24int beatCount = 1;
25
26void setup()
27{
28  //set input/output pins
29  pinMode(SPEAKER, OUTPUT);
30  pinMode(YELLOW_LED, OUTPUT);
31  pinMode(BLUE_LED1, OUTPUT);
32  pinMode(BLUE_LED2, OUTPUT);
33  pinMode(BLUE_LED3, OUTPUT);
34  pinMode(DIAL, INPUT);
35  
36  //declare rows and columns of lcd
37  lcd.begin(16, 2);
38}
39
40void loop()
41{
42  //map the dial's value to the beats per minute range of 50 to 300
43  int bpm = map(analogRead(DIAL),0, 1023, 50, 300);
44  
45  //lcd print
46  lcd.setCursor(0,0);
47  lcd.print("Time Sig: 4/4");
48  lcd.setCursor(0, 1);
49  lcd.print("BPM: ");
50  lcd.setCursor(5, 1);
51  lcd.print(bpm);
52  //clear third digit on display if bpm is two digits
53  if(bpm < 100) {
54    lcd.setCursor(7, 1);
55    lcd.print("  ");
56  }
57 
58  //set time of each individual beat based on bpm
59  //60000 = 1 minute
60  int beatInterval = 60000 / bpm;
61  
62  //in 4/4 time signature there are four beats
63  //first beat of each 4 beats will be a different tone
64  //and different color light to indicate start of new measure
65  if(beatCount == 1) {
66    //higher note at start of measure
67    //tone plays for half the length of the beat to leave a pause
68    tone(SPEAKER, 1025, beatInterval / 2);
69    //turn on and off appropraite lights
70    digitalWrite(YELLOW_LED, HIGH);
71    digitalWrite(BLUE_LED1, LOW);
72    digitalWrite(BLUE_LED2, LOW);
73    digitalWrite(BLUE_LED3, LOW);
74    //keep respective light on for whole beat
75    delay(beatInterval);
76  } else {
77    //lower tone for the rest of the measure
78    tone(SPEAKER, 775, beatInterval / 2);
79    //tone is the same for beats 2-4
80    //but will have different lights on
81    if(beatCount == 2) {
82      digitalWrite(BLUE_LED1, HIGH);
83      digitalWrite(YELLOW_LED, LOW);
84      digitalWrite(BLUE_LED2, LOW);
85      digitalWrite(BLUE_LED3, LOW);
86      delay(beatInterval);
87    } else if(beatCount == 3) {
88      digitalWrite(BLUE_LED2, HIGH);
89      digitalWrite(YELLOW_LED, LOW);
90      digitalWrite(BLUE_LED1, LOW);
91      digitalWrite(BLUE_LED3, LOW);
92      delay(beatInterval);
93    } else {
94      digitalWrite(BLUE_LED3, HIGH);
95      digitalWrite(YELLOW_LED, LOW);
96      digitalWrite(BLUE_LED1, LOW);
97      digitalWrite(BLUE_LED2, LOW);
98      delay(beatInterval);
99    }
100  }
101  
102  //incriment beat count or reset beat count after 4
103  if(beatCount < 4)
104    beatCount++;
105  else
106    beatCount = 1;
107  
108}