feat: add RC32 and RC52 buzzer example

README.md

@@ -32,6 +32,7 @@ The library declares these Arduino dependencies:
   [claws/BH1750](https://github.com/claws/BH1750)
 - `Adafruit NeoPixel`
 - `ESP32Servo` for ESP32-based RadioCore boards
+- `NonBlockingRTTTL` version 1.4.0 or newer for non-blocking buzzer melodies
 
 Dependency-aware Arduino tools can install these libraries automatically.
 RadioCore_Kit does not copy, wrap, or re-export them.
@@ -61,6 +62,7 @@ compile time.
 | `Soil_Moisture_Read` | Read and calibrate an analog soil moisture sensor | [Guide](examples/Soil_Moisture_Read/README.md) |
 | `NV3001B_Display` | Exercise the 128-by-220 color TFT | [Guide](examples/NV3001B_Display/README.md) |
 | `WS2812` | Run a three-color breathing animation | [Sketch](examples/WS2812/WS2812.ino) |
+| `Buzzer_Control` | Play and repeat an RTTTL melody through the board-designated buzzer output | [Sketch](examples/Buzzer_Control/Buzzer_Control.ino) |
 | `Motor_Control` | Drive two direction inputs on an external motor driver | [Sketch](examples/Motor_Control/Motor_Control.ino) |
 | `Relay_Control` | Toggle an active-high relay module | [Sketch](examples/Relay_Control/Relay_Control.ino) |
 | `Servo_Control` | Control both channels of an RS-SV01 servo driver | [Sketch](examples/Servo_Control/Servo_Control.ino) |
@@ -83,9 +85,10 @@ A new board declares only the capabilities it supports:
   `CO01_Read`, and `Soil_Moisture_Read`; CO01 also requires its control pin.
 - NV3001B pins, active levels, SPI frequency, and one supported display
   transport for `NV3001B_Display`.
-- A data pin for `WS2812`, two motor-driver inputs for `Motor_Control`, a relay
-  output and active level for `Relay_Control`, and two PWM pins plus driver
-  enable facts for `Servo_Control`.
+- A data pin for `WS2812`, a buzzer output pin and any shared peripheral power
+  control required by `Buzzer_Control`, two motor-driver inputs for
+  `Motor_Control`, a relay output and active level for `Relay_Control`, and two
+  PWM pins plus driver enable facts for `Servo_Control`.
 
 The shared examples currently support the ESP32/WiFi Kit Series and Heltec
 nRF52 peripheral APIs used by RC32, RCC6, and RC52. A board with a different

docs/CONTEXT.md

@@ -76,6 +76,10 @@ An external chain of individually addressable RGB pixels controlled by a
 single data signal.
 _Avoid_: generic RGB LED, onboard LED
 
+**Buzzer output**:
+The board-designated PWM output connected to a piezo buzzer or buzzer module.
+_Avoid_: tone pin, speaker output
+
 **Motor control input**:
 One of a pair of digital direction signals connected to an external motor
 driver; together the pair selects a stopped state or a drive direction.

examples/Buzzer_Control/Buzzer_Control.ino

@@ -0,0 +1,86 @@
+/*
+ * Plays the Meshtastic default RTTTL notification melody through the
+ * board-designated buzzer output: RC32 GPIO48 or RC52 P0.05. RCC6 has no
+ * supported buzzer output.
+ *
+ * Playback is non-blocking. The melody repeats five seconds after it finishes.
+ * Define BUZZER_RTTTL or BUZZER_REPLAY_INTERVAL_MS before this sketch content
+ * to use a different melody or replay interval.
+ */
+#ifndef BUZZER_RTTTL
+#define BUZZER_RTTTL                                                          \
+  "24:d=32,o=5,b=565:f6,p,f6,4p,p,f6,p,f6,2p,p,b6,p,b6,p,b6,p,b6,p,b,p," \
+  "b,p,b,p,b,p,b,p,b,p,b,p,b,1p.,2p.,p"
+#endif
+
+#ifndef BUZZER_REPLAY_INTERVAL_MS
+#define BUZZER_REPLAY_INTERVAL_MS 5000UL
+#endif
+
+#include <Arduino.h>
+#include <RadioCore_Kit.h>
+
+#if !RADIOCORE_HAS_BUZZER
+#error "Buzzer_Control requires a RadioCore board with a supported buzzer output."
+#else
+
+#include <NonBlockingRtttl.h>
+
+namespace {
+
+constexpr char kRingtone[] = BUZZER_RTTTL;
+
+uint32_t playbackFinishedAt = 0;
+bool replayPending = false;
+
+void startPlayback(bool replay)
+{
+  rtttl::begin(RADIOCORE_BUZZER_PIN, kRingtone);
+  replayPending = false;
+  Serial.println(
+      replay ? F("Buzzer replay started") : F("Buzzer playback started"));
+}
+
+} // namespace
+
+void setup()
+{
+  Serial.begin(115200);
+
+  pinMode(RADIOCORE_BUZZER_PIN, OUTPUT);
+  digitalWrite(RADIOCORE_BUZZER_PIN, LOW);
+
+#if RADIOCORE_HAS_SENSOR_POWER_CTRL
+  pinMode(RADIOCORE_SENSOR_POWER_CTRL_PIN, OUTPUT);
+  digitalWrite(
+      RADIOCORE_SENSOR_POWER_CTRL_PIN,
+      RADIOCORE_SENSOR_POWER_ON);
+  delay(RADIOCORE_SENSOR_POWER_WARMUP_MS);
+#endif
+
+  Serial.println();
+  Serial.println(F("RadioCore buzzer control example"));
+  startPlayback(false);
+}
+
+void loop()
+{
+  if (rtttl::isPlaying()) {
+    rtttl::play();
+
+    if (!rtttl::isPlaying()) {
+      playbackFinishedAt = millis();
+      replayPending = true;
+      Serial.println(F("Buzzer playback finished"));
+    }
+
+    return;
+  }
+
+  if (replayPending &&
+      millis() - playbackFinishedAt >= BUZZER_REPLAY_INTERVAL_MS) {
+    startPlayback(true);
+  }
+}
+
+#endif // RADIOCORE_HAS_BUZZER

library.properties

@@ -8,4 +8,4 @@ category=Device Control
 url=https://github.com/HelTecAutomation/RadioCore_Library
 architectures=*
 includes=RadioCore_Kit.h
-depends=Adafruit BME280 Library, BH1750 (>=1.3.0), Adafruit NeoPixel, ESP32Servo
+depends=Adafruit BME280 Library, BH1750 (>=1.3.0), Adafruit NeoPixel, ESP32Servo, NonBlockingRTTTL (>=1.4.0)

src/RadioCoreBoardConfig.h

@@ -23,6 +23,7 @@
 #define RADIOCORE_NV3001B_USE_HARDWARE_SPI 0
 #define RADIOCORE_NV3001B_USE_SOFTWARE_SPI 0
 #define RADIOCORE_HAS_WS2812 0
+#define RADIOCORE_HAS_BUZZER 0
 #define RADIOCORE_HAS_MOTOR_CONTROL 0
 #define RADIOCORE_HAS_RELAY_CONTROL 0
 #define RADIOCORE_HAS_SERVO_CONTROL 0

src/boards/heltec_rc32.h

@@ -66,6 +66,9 @@
 #define RADIOCORE_HAS_WS2812 1
 #define RADIOCORE_WS2812_DATA_PIN 5
 
+#define RADIOCORE_HAS_BUZZER 1
+#define RADIOCORE_BUZZER_PIN 48
+
 #define RADIOCORE_HAS_MOTOR_CONTROL 1
 #define RADIOCORE_MOTOR_IN1_PIN 41
 #define RADIOCORE_MOTOR_IN2_PIN 42

src/boards/heltec_rc52.h

@@ -57,6 +57,9 @@
 #define RADIOCORE_HAS_WS2812 1
 #define RADIOCORE_WS2812_DATA_PIN (0 + 9) // P0.09
 
+#define RADIOCORE_HAS_BUZZER 1
+#define RADIOCORE_BUZZER_PIN (0 + 5) // P0.05
+
 #define RADIOCORE_HAS_MOTOR_CONTROL 1
 #define RADIOCORE_MOTOR_IN1_PIN (32 + 1) // P1.01
 #define RADIOCORE_MOTOR_IN2_PIN (0 + 20) // P0.20

src/boards/heltec_rcc6.h

@@ -46,6 +46,8 @@
 #define RADIOCORE_HAS_WS2812 1
 #define RADIOCORE_WS2812_DATA_PIN 2
 
+#define RADIOCORE_HAS_BUZZER 0
+
 #define RADIOCORE_HAS_MOTOR_CONTROL 1
 #define RADIOCORE_MOTOR_IN1_PIN 3
 #define RADIOCORE_MOTOR_IN2_PIN 4