Extract buzzer to separate file

bme280.ino

@@ -2,7 +2,7 @@
 
 BME280 sensor;
 
-void initTemperature() {
+void initBME280() {
   sensor.init();
 }
 

buzzer.ino

@@ -0,0 +1,46 @@
+#include <Arduino.h>
+
+SAMDTimer BuzzerTimer(TIMER_TC5);
+bool attached = false;
+
+void initBuzzer() {
+  pinMode(BUZZER_PIN, OUTPUT);
+}
+
+volatile bool buzzing = false;
+void buzzerISR() {
+  digitalWrite(BUZZER_PIN, buzzing ? LOW : HIGH);
+  buzzing = !buzzing;
+  //digitalToggle(BUZZER_PIN);
+}
+
+void buzz() {
+  if (attached)
+    BuzzerTimer.enableTimer();
+  else
+    BuzzerTimer.attachInterrupt(BUZZER_FREQ *2, buzzerISR);
+}
+
+void noBuzz() {
+  BuzzerTimer.disableTimer();
+}
+
+/*
+// https://forum.arduino.cc/t/adding-a-toggle-function-to-wiring-digital-c/975608
+void digitalToggle(uint8_t pin) {
+  uint8_t timer = digitalPinToTimer(pin);
+  uint8_t bit = digitalPinToBitMask(pin);
+  uint8_t port = digitalPinToPort(pin);
+  volatile uint8_t *out;
+  
+  if (port == NOT_A_PIN) return;
+  if (timer != NOT_ON_TIMER) turnOffPWM(timer);
+  
+  out = portOutputRegister(port);
+  
+  uint8_t oldSREG = SREG;
+  cli();
+  *out ^= bit;
+  SREG = oldSREG;
+}
+*/

metronom.ino

@@ -2,7 +2,6 @@
 #include "SAMD_ISR_Timer.h"
 
 SAMDTimer TaskTimer(TIMER_TC3);
-SAMDTimer BuzzerTimer(TIMER_TC5);
 SAMD_ISR_Timer TasksISRs;
 
 void TasksHandler(void) { TasksISRs.run(); }
@@ -26,40 +25,25 @@ volatile float temperature = 0.0;
 
 void setup() {
   initButton();
-  initTemperature();
+  initBME280();
+  initBuzzer();
   initTube();
 
-  pinMode(BUZZER_PIN, OUTPUT);
+  TaskTimer.attachInterruptInterval_MS(20, TasksHandler);
-  BuzzerTimer.attachInterrupt(BUZZER_FREQ *2, buzz);
-  BuzzerTimer.disableTimer();
-
-  TaskTimer.attachInterruptInterval_MS(25, TasksHandler);
   TasksISRs.setInterval(PERIOD_MS, runMetronome);
   TasksISRs.setInterval(PERIOD_MS, readTemperature);
   TasksISRs.setInterval(PERIOD_MS, updateTube);
 }
 
-volatile bool buzzing = false;
-void buzz() {
-  digitalWrite(BUZZER_PIN, buzzing ? LOW : HIGH);
-  buzzing = !buzzing;
-}
-
-void stopBuzzer() {
-  BuzzerTimer.disableTimer();
-  digitalWrite(BUZZER_PIN, LOW);
-}
-
 void runMetronome() {
   if (countdown > 0) {
     countdown -= 1;
 
     digitalWrite(BUTTON_LED_PIN, countdown % 2 ? HIGH : LOW);
   } else if (countdown == 0) {
-    TasksISRs.setTimeout(100, stopBuzzer);
+    TasksISRs.setTimeout(100, noBuzz);
-    BuzzerTimer.enableTimer();
+    buzz();
   }
 }
 
-void loop() {
+void loop() {}
-}

tube.ino

@@ -3,7 +3,7 @@
 Seeed_Digital_Tube tube;
 
 void initTube() {
-  // Wire initialized by temperature sensor
+  // Wire initialized by BME280 sensor
   tube.setTubeType(TYPE_4, TYPE_4_DEFAULT_I2C_ADDR);
   tube.setBrightness(15);
   tube.setBlinkRate(BLINK_OFF);