Upload main.c

led_countdown/main.c

+#include "pico/stdlib.h"
+#include "hardware/pwm.h"
+#include "hardware/clocks.h"
+
+const int FIRST_LED_PIN = 0;
+const int LAST_LED_PIN = 28;
+const int BUZZER_PIN = 18;
+
+void sound_buzzer() {
+    gpio_set_function(BUZZER_PIN, GPIO_FUNC_PWM);
+    uint slice_num = pwm_gpio_to_slice_num(BUZZER_PIN);
+    uint16_t pwm_count = pwm_gpio_to_channel(BUZZER_PIN);
+
+    uint frequency = 200;
+
+    float divider = 1.0f;
+    uint32_t sys_clk_freq = clock_get_hz(clk_sys);
+    uint32_t wrap_value = sys_clk_freq / (divider * frequency);
+    while (wrap_value > 65535) {
+        divider *= 2.0f;
+        wrap_value = sys_clk_freq / (divider * frequency);
+    }
+
+    pwm_set_clkdiv(slice_num, divider);
+    pwm_set_wrap(slice_num, wrap_value);
+
+    uint32_t dutyCycle = wrap_value / 2;
+    pwm_set_chan_level(slice_num, pwm_count, dutyCycle);
+
+    pwm_set_enabled(slice_num, true);
+    sleep_ms(200);  // Sound the buzzer for 200 milliseconds
+    pwm_set_enabled(slice_num, false);
+}
+
+bool valid_led(int pin) {
+    if (pin == 23 || pin == 24 || pin == 25) {
+        return false;
+    } else {
+        return true;
+    }
+}
+
+
+int main() {
+    // Use for debugging
+    stdio_init_all();
+
+    // Initialise LED pins as output
+    for (int pin = FIRST_LED_PIN; pin <= LAST_LED_PIN; pin++) {
+        if (valid_led(pin)) {
+        gpio_init(pin);
+        gpio_set_dir(pin, GPIO_OUT);
+        }
+    }
+
+    // Turn on all LEDs
+    for (int pin = FIRST_LED_PIN; pin <= LAST_LED_PIN; pin++) {
+        if (valid_led(pin)) {
+        gpio_put(pin, 1);
+        }
+    }
+    sleep_ms(1000);
+
+    // Turn off each LED one by one each second
+    for (int pin = FIRST_LED_PIN; pin <= LAST_LED_PIN; pin++) {
+        if (valid_led(pin)) {
+            gpio_put(pin, 0);
+            sleep_ms(1000);
+        }
+    }
+
+    sound_buzzer();
+
+
+    return 0;
+}