I'm working on a project using an Arduino with a keypad, an LCD, and a buzzer. The idea is to set a code, and once the code is set, a countdown starts. During this countdown, the buzzer is supposed to beep at different frequencies depending on the remaining time:
However, I've encountered a problem where, when the buzzer should beep more fast, the beeping frequency doesn't change as expected. It continues to beep with the same interval as before.
Here's my code:
#include <Keypad.h>
#include <LiquidCrystal_I2C.h>
#include <Tone.h>
Tone tone1;
const byte ROWS = 4; // four rows
const byte COLS = 4; // four columns
char keys[ROWS][COLS] = {
{'1', '2', '3', 'A'},
{'4', '5', '6', 'B'},
{'7', '8', '9', 'C'},
{'*', '0', '#', 'D'}
};
byte rowPins[ROWS] = {5, 6, 7, 8}; // Connect row pins of the keypad to digital pins 5, 6, 7, 8
byte colPins[COLS] = {9, 10, 11, 12}; // Connect to the column pinouts of the keypad
Keypad keypad = Keypad(makeKeymap(keys), rowPins, colPins, ROWS, COLS);
int currentLength = 0;
char entered[4];
char password[4] = {'1', '2', '3', '4'};
bool settingCode = true; // Flag to indicate code setting mode
String newCode = ""; // Variable to store the new code
LiquidCrystal_I2C lcd(0x27, 16, 2); // Set the LCD address and dimensions
unsigned long previousMillis = 0;
const long interval = 1000; // Interval of 1 second
int countdown = 61; // Initial countdown value in seconds
void setup() {
tone1.begin(4); // Initialize the buzzer on pin 4
lcd.init(); // Initialize the LCD
lcd.backlight(); // Turn on backlight
lcd.setCursor(0, 0);
lcd.print("Set Code:");
pinMode(4, OUTPUT); // Set pin 4 as the buzzer pin
}
void loop() {
if (settingCode) {
char key = keypad.getKey();
if (key != NO_KEY && currentLength < 4) {
if (key == '#') {
currentLength = 0;
lcd.clear();
lcd.setCursor(0, 0);
lcd.print("Set Code:");
} else if (key != '*' && key != '#') {
lcd.setCursor(currentLength, 1);
lcd.print('*');
newCode += key;
currentLength++;
tone1.play(500); // Play a quieter tone when a key is pressed during code setting
delay(100);
tone1.stop(); // Stop the tone after the delay
}
}
if (currentLength == 4) {
lcd.clear();
lcd.setCursor(0, 0);
lcd.print("Code Set!");
tone1.play(600); // Play a slightly louder tone to indicate code setting completion
delay(2000);
tone1.stop(); // Stop the tone after the delay
lcd.clear();
lcd.print("Enter Code:");
settingCode = false;
currentLength = 0;
// Start the timer
previousMillis = millis();
}
} else {
unsigned long currentMillis = millis();
if (currentMillis - previousMillis >= interval) {
previousMillis = currentMillis;
countdown--;
lcd.setCursor(12, 0); // Set the cursor position for the timer display
lcd.print(" "); // Clear previous timer value
lcd.setCursor(12, 0);
lcd.print(countdown);
// Play beeping sound based on countdown value
if (countdown <= 60 && countdown > 30) {
tone1.play(2000); // Play the beep sound
delay(500); // Beep every 0.5 seconds
tone1.stop();
} else if (countdown <= 30 && countdown > 10) {
tone1.play(2000); // Play the beep sound
delay(250); // Beep every 0.25 seconds
tone1.stop();
} else if (countdown <= 10 && countdown > 5) {
tone1.play(2000); // Play the beep sound
delay(125); // Beep every 0.125 seconds
tone1.stop();
} else if (countdown <= 5 && countdown > 0) {
tone1.play(2000); // Play the beep sound
delay(63); // Beep every 0.063 seconds
tone1.stop();
} else if (countdown == 0) {
tone1.play(2000); // Continuous beeping
delay(50); // Beep every 0.05 seconds
tone1.stop();
}
}
char key = keypad.getKey();
if (key != NO_KEY && currentLength < 4) {
if (key == '#') {
currentLength = 0;
lcd.clear();
lcd.setCursor(0, 0);
lcd.print("Enter Code:");
} else if (key != '*' && key != '#') {
lcd.setCursor(currentLength, 1);
lcd.print('*');
entered[currentLength] = key;
currentLength++;
tone1.play(500); // Play a quieter tone when a key is pressed during code entry
delay(100);
tone1.stop(); // Stop the tone after the delay
}
}
if (currentLength == 4) {
if (entered[0] == newCode[0] && entered[1] == newCode[1] && entered[2] == newCode[2] && entered[3] == newCode[3]) {
lcd.clear();
lcd.setCursor(0, 0);
lcd.print("Bomb Defused");
tone1.play(700); // Play a slightly louder tone to indicate successful code entry
delay(2500);
tone1.stop(); // Stop the tone after the delay
lcd.clear();
settingCode = true;
newCode = "";
lcd.setCursor(0, 0);
lcd.print("Set Code:");
currentLength = 0;
countdown = 30; // Reset the countdown timer
} else {
lcd.clear();
lcd.setCursor(0, 0);
lcd.print("Wrong Password!");
tone1.play(400); // Play a slightly louder tone to indicate wrong password
delay(1500);
tone1.stop(); // Stop the tone after the delay
lcd.clear();
lcd.setCursor(0, 0);
lcd.print("Enter Code:");
currentLength = 0;
countdown -= 5; // Decrease the timer by 5 seconds for wrong password
if (countdown < 0) {
countdown = 0; // Ensure the countdown doesn't go negative
}
lcd.setCursor(12, 0); // Update the timer display on the LCD
lcd.print(" "); // Clear previous timer value
lcd.setCursor(12, 0);
lcd.print(countdown);
if (countdown <= 10) {
lcd.setCursor(1, 7);
lcd.print("Code: ");
lcd.setCursor(1, 13);
lcd.print(newCode);
}
}
}
}
}
