Added buzzer playing demo song

src/SmartRFID.cpp

@@ -41,7 +41,7 @@ String SmartRFID::readTag()
         Serial.println(s);
         return s;
     }
-    return "error_reading_tag";
+    return "no_tag_detected";
 }
 
 /**

src/main.cpp

@@ -1,10 +1,12 @@
 #include "main.hpp"
 #include "secrets.hpp"
+#include "song.h"
 
 #define WIRE Wire
 
 #define SERVO_PIN 14         // D5
 #define POTENTIOMETER_PIN A0 // A0
+#define BUZZER_PIN 12        // D6
 
 // buttons
 #define TACTILE_BTN_LEFT 0  // D3
@@ -94,6 +96,9 @@ void loop()
   {
     smartDisplay.printWaitForRFIDScreen();
 
+    playSong();
+
+    // this blocks execution until a tag has been detected
     String uid = smartRFID.readTag();
 
     display.println(uid);
@@ -173,6 +178,27 @@ void loop()
   };
 }
 
+void playSong()
+{
+  int size = sizeof(durations) / sizeof(int);
+
+  for (int note = 0; note < size; note++)
+  {
+    // to calculate the note duration, take one second divided by the note type.
+    // e.g. quarter note = 1000 / 4, eighth note = 1000/8, etc.
+    int duration = 1000 / durations[note];
+    tone(BUZZER_PIN, melody[note], duration);
+
+    // to distinguish the notes, set a minimum time between them.
+    // the note's duration + 30% seems to work well:
+    int pauseBetweenNotes = duration * 1.30;
+    delay(pauseBetweenNotes);
+
+    // stop the tone playing:
+    noTone(BUZZER_PIN);
+  }
+}
+
 void toggle_led()
 {
   digitalWrite(LED_BUILTIN, !digitalRead(LED_BUILTIN));

src/main.hpp

@@ -17,6 +17,7 @@
 #include "TeaNetworking.hpp"
 #include "TeaData.hpp"
 
+void playSong();
 bool toggle_led(void *);
 void printMsg(const String &s);
 void printMsg(unsigned long l);

src/pitches.h

@@ -0,0 +1,96 @@
+// -------------------------------------------------
+// Copyright (c) 2021 HiBit <https://www.hibit.dev>
+// -------------------------------------------------
+
+#define NOTE_B0  31
+#define NOTE_C1  33
+#define NOTE_CS1 35
+#define NOTE_D1  37
+#define NOTE_DS1 39
+#define NOTE_E1  41
+#define NOTE_F1  44
+#define NOTE_FS1 46
+#define NOTE_G1  49
+#define NOTE_GS1 52
+#define NOTE_A1  55
+#define NOTE_AS1 58
+#define NOTE_B1  62
+#define NOTE_C2  65
+#define NOTE_CS2 69
+#define NOTE_D2  73
+#define NOTE_DS2 78
+#define NOTE_E2  82
+#define NOTE_F2  87
+#define NOTE_FS2 93
+#define NOTE_G2  98
+#define NOTE_GS2 104
+#define NOTE_A2  110
+#define NOTE_AS2 117
+#define NOTE_B2  123
+#define NOTE_C3  131
+#define NOTE_CS3 139
+#define NOTE_DB3 139
+#define NOTE_D3  147
+#define NOTE_DS3 156
+#define NOTE_EB3 156
+#define NOTE_E3  165
+#define NOTE_F3  175
+#define NOTE_FS3 185
+#define NOTE_G3  196
+#define NOTE_GS3 208
+#define NOTE_A3  220
+#define NOTE_AS3 233
+#define NOTE_B3  247
+#define NOTE_C4  262
+#define NOTE_CS4 277
+#define NOTE_D4  294
+#define NOTE_DS4 311
+#define NOTE_E4  330
+#define NOTE_F4  349
+#define NOTE_FS4 370
+#define NOTE_G4  392
+#define NOTE_GS4 415
+#define NOTE_A4  440
+#define NOTE_AS4 466
+#define NOTE_B4  494
+#define NOTE_C5  523
+#define NOTE_CS5 554
+#define NOTE_D5  587
+#define NOTE_DS5 622
+#define NOTE_E5  659
+#define NOTE_F5  698
+#define NOTE_FS5 740
+#define NOTE_G5  784
+#define NOTE_GS5 831
+#define NOTE_A5  880
+#define NOTE_AS5 932
+#define NOTE_B5  988
+#define NOTE_C6  1047
+#define NOTE_CS6 1109
+#define NOTE_D6  1175
+#define NOTE_DS6 1245
+#define NOTE_E6  1319
+#define NOTE_F6  1397
+#define NOTE_FS6 1480
+#define NOTE_G6  1568
+#define NOTE_GS6 1661
+#define NOTE_A6  1760
+#define NOTE_AS6 1865
+#define NOTE_B6  1976
+#define NOTE_C7  2093
+#define NOTE_CS7 2217
+#define NOTE_D7  2349
+#define NOTE_DS7 2489
+#define NOTE_E7  2637
+#define NOTE_F7  2794
+#define NOTE_FS7 2960
+#define NOTE_G7  3136
+#define NOTE_GS7 3322
+#define NOTE_A7  3520
+#define NOTE_AS7 3729
+#define NOTE_B7  3951
+#define NOTE_C8  4186
+#define NOTE_CS8 4435
+#define NOTE_D8  4699
+#define NOTE_DS8 4978
+#define REST     0

src/song.h

@@ -0,0 +1,43 @@
+#include "pitches.h"
+
+int melody[] = {
+  REST, REST, REST, NOTE_DS4, 
+  NOTE_E4, REST, NOTE_FS4, NOTE_G4, REST, NOTE_DS4,
+  NOTE_E4, NOTE_FS4,  NOTE_G4, NOTE_C5, NOTE_B4, NOTE_E4, NOTE_G4, NOTE_B4,   
+  NOTE_AS4, NOTE_A4, NOTE_G4, NOTE_E4, NOTE_D4, 
+  NOTE_E4, REST, REST, NOTE_DS4,
+  
+  NOTE_E4, REST, NOTE_FS4, NOTE_G4, REST, NOTE_DS4,
+  NOTE_E4, NOTE_FS4,  NOTE_G4, NOTE_C5, NOTE_B4, NOTE_G4, NOTE_B4, NOTE_E5,
+  NOTE_DS5,   
+  NOTE_D5, REST, REST, NOTE_DS4, 
+  NOTE_E4, REST, NOTE_FS4, NOTE_G4, REST, NOTE_DS4,
+  NOTE_E4, NOTE_FS4,  NOTE_G4, NOTE_C5, NOTE_B4, NOTE_E4, NOTE_G4, NOTE_B4,   
+  
+  NOTE_AS4, NOTE_A4, NOTE_G4, NOTE_E4, NOTE_D4, 
+  NOTE_E4, REST,
+  REST, NOTE_E5, NOTE_D5, NOTE_B4, NOTE_A4, NOTE_G4, NOTE_E4,
+  NOTE_AS4, NOTE_A4, NOTE_AS4, NOTE_A4, NOTE_AS4, NOTE_A4, NOTE_AS4, NOTE_A4,   
+  NOTE_G4, NOTE_E4, NOTE_D4, NOTE_E4, NOTE_E4, NOTE_E4
+};
+
+int durations[] = {
+  2, 4, 8, 8, 
+  4, 8, 8, 4, 8, 8,
+  8, 8,  8, 8, 8, 8, 8, 8,   
+  2, 16, 16, 16, 16, 
+  2, 4, 8, 4,
+  
+  4, 8, 8, 4, 8, 8,
+  8, 8,  8, 8, 8, 8, 8, 8,
+  1,   
+  2, 4, 8, 8, 
+  4, 8, 8, 4, 8, 8,
+  8, 8,  8, 8, 8, 8, 8, 8,   
+  
+  2, 16, 16, 16, 16, 
+  4, 4,
+  4, 8, 8, 8, 8, 8, 8,
+  16, 8, 16, 8, 16, 8, 16, 8,   
+  16, 16, 16, 16, 16, 2
+};