Custom Chess Clock

1#include <LCD-I2C.h>
2LCD_I2C lcd(0x27, 16, 2);
3
4#define RIGHT true
5#define LEFT false
6
7const int leftButton = 4;
8const int rightButton = 3;
9const int limit = 2;
10const int Rpot = A6;
11const int Lpot = A7;
12
13volatile unsigned long NOW;
14volatile unsigned long THEN;
15
16volatile long Rtime;
17volatile long Ltime;
18
19volatile bool limitState;
20
21void setup() {
22  Serial.begin(9600);
23  pinMode(leftButton, INPUT);
24  pinMode(rightButton, INPUT);
25  pinMode(limit, INPUT);
26  pinMode(Rpot, INPUT);
27  pinMode(Lpot, INPUT);
28
29  attachInterrupt(digitalPinToInterrupt(limit), timeTrigger, CHANGE);
30
31  limitState = digitalRead(limit);
32
33  lcd.begin();
34  lcd.display();
35  lcd.backlight();
36}
37
38void reset() {
39  Rtime = 100 * 60 * map(analogRead(Rpot), 0, 1023, 300, 0);
40  Ltime = 100 * 60 * map(analogRead(Lpot), 0, 1023, 300, 0);
41  printTime();
42
43  return delay(500);  // prevent bouncing
44}
45
46void timeTrigger() {
47  static unsigned long last_interrupt_time = 0;
48  unsigned long interrupt_time = millis();
49
50  if (interrupt_time - last_interrupt_time > 200) { limitState = !limitState; }
51
52  last_interrupt_time = interrupt_time;
53}
54
55long deduction() {
56  NOW = millis();
57  long elapsed = NOW - THEN;
58
59  THEN = NOW;
60
61  return elapsed;
62}
63
64void countDown() {
65  if (limitState == RIGHT) { Rtime -= deduction(); }
66  if (limitState == LEFT) { Ltime -= deduction(); }
67
68  Rtime = max(Rtime, 0);
69  Ltime = max(Ltime, 0);
70}
71
72void printTime() {
73  /* Serial.print("Rtime: ");
74  Serial.print(Rtime);
75
76  Serial.print("    ");
77
78  Serial.print("Ltime: ");
79  Serial.print(Ltime);
80
81  Serial.print("    ");
82
83  Serial.print("deduction: ");
84  Serial.print(deduction());
85
86  Serial.print("    ");
87
88  Serial.print("limitState: ");
89  Serial.println(limitState); */
90
91  int r_total_s = Rtime / 1000;
92  int l_total_s = Ltime / 1000;
93
94  int r_time_m = r_total_s / 60;
95  int r_time_s = r_total_s % 60;
96
97  int l_time_m = l_total_s / 60;
98  int l_time_s = l_total_s % 60;
99
100
101
102  lcd.setCursor(0, 0);
103  lcd.print("00:00");
104
105  if (r_time_m < 10) {
106    lcd.setCursor(1, 0);
107  } else {
108    lcd.setCursor(0, 0);
109  }
110  lcd.print(r_time_m);
111
112  if (r_time_s < 10) {
113    lcd.setCursor(4, 0);
114  } else {
115    lcd.setCursor(3, 0);
116  }
117
118  lcd.print(r_time_s);
119
120
121  lcd.setCursor(11, 0);
122  lcd.print("00:00");
123
124  if (l_time_m < 10) {
125    lcd.setCursor(12, 0);
126  } else {
127    lcd.setCursor(11, 0);
128  }
129  lcd.print(l_time_m);
130
131  if (l_time_s < 10) {
132    lcd.setCursor(15, 0);
133  } else {
134    lcd.setCursor(14, 0);
135  }
136
137  lcd.print(l_time_s);
138}
139
140void start() {
141  THEN = millis();
142
143  while (Rtime > 0 && Ltime > 0) {
144    boolean shouldReset = digitalRead(leftButton) && digitalRead(rightButton);
145
146    if (shouldReset) { return reset(); }
147
148    countDown();
149
150    printTime();
151  }
152}
153
154void loop() {
155  if (digitalRead(leftButton)) { reset(); }
156
157  if (digitalRead(rightButton)) { start(); }
158}