#include #include #include // === Pin definitions === #define MIC_PIN 32 // Analog input for microphone amplifier output (e.g. MAX9814 OUT) #define SPEAKER_PIN 25 // DAC output for audio amplifier/speaker #define LED_PIN 23 // Single LED lights up when receiving audio #define PTT_PIN 34 // Push-to-Talk button (uses INPUT_PULLUP logic) #define POT_PIN 35 // Linear 10k potentiometer for pitch control (playback speed) #define AMP_SHUTDOWN_PIN 21 // PAM8302A shutdown pin (active HIGH: amp ON, LOW: amp OFF) #define NEOPIX_MIC_PIN 19 // Data pin for 24-LED NeoPixel ring (for microphone VU) #define NEOPIX_MIC_NUM 24 #define NEOPIX_RX_PIN 18 // Data pin for 12-LED NeoPixel ring (for received audio VU) #define NEOPIX_RX_NUM 12 #define AUDIO_BLOCK 128 // Number of audio samples per packet Adafruit_NeoPixel micRing(NEOPIX_MIC_NUM, NEOPIX_MIC_PIN, NEO_GRB + NEO_KHZ800); // Microphone VU (big ring) Adafruit_NeoPixel rxRing(NEOPIX_RX_NUM, NEOPIX_RX_PIN, NEO_GRBW + NEO_KHZ800); // Received audio VU (small ring, white for clarity) // === MAC address of the other ESP32 === // CHANGE this to the address of your partner board! uint8_t peer_mac[6] = { 0xA8, 0x42, 0xE3, 0x90, 0x9D, 0xD0 }; // === Buffers for audio data === uint8_t audioBlock[AUDIO_BLOCK]; // For sending audio volatile bool newBlock = false; // Set true when a new audio packet arrives uint8_t rxBlock[AUDIO_BLOCK]; // For receiving audio portMUX_TYPE mux = portMUX_INITIALIZER_UNLOCKED; // For interrupt safety // === Noise Gate === const int noiseThreshold = 10; // Increase to reduce background noise, lower for more sensitivity // === Amp ON delay timeout === unsigned long lastAudioTime = 0; const unsigned long ampTimeout = 150; // ms after last audio before turning amp OFF // === VU-Meter helper: classic green → yellow → red (works for both GRB and GRBW) === void showVUMeter(Adafruit_NeoPixel &ring, int numPixels, float loudness, float maxLoudness, float brightness = 0.2) { int level = map(loudness, 0, maxLoudness, 0, numPixels); if (level < 0) level = 0; if (level > numPixels) level = numPixels; for (int i = 0; i < numPixels; i++) { uint32_t color = 0; float pos = (float)i / numPixels; if (i < level) { // Classic VU colors: green, yellow, red (dimmable) uint8_t r = 0, g = 0, b = 0, w = 0; if (pos < 0.6) { r = 0; g = 255; b = 0; } else if (pos < 0.8) { r = 255; g = 255; b = 0; } else { r = 255; g = 0; b = 0; } r = uint8_t(r * brightness); g = uint8_t(g * brightness); b = uint8_t(b * brightness); if (numPixels == NEOPIX_RX_NUM) // 12er RX ring: white + color color = ring.Color(r, g, b, uint8_t(64 * brightness)); else // 24er MIC ring: classic color color = ring.Color(r, g, b); } ring.setPixelColor(i, color); } ring.show(); } // === ESP-NOW: Called when a packet is received === void onReceive(const esp_now_recv_info_t *info, const uint8_t *data, int len) { // Only accept audio when NOT sending yourself! if (len == AUDIO_BLOCK && !newBlock && digitalRead(PTT_PIN) == LOW) { portENTER_CRITICAL_ISR(&mux); memcpy(rxBlock, data, AUDIO_BLOCK); // Copy received data to buffer newBlock = true; // Mark as ready for playback portEXIT_CRITICAL_ISR(&mux); lastAudioTime = millis(); // Update last audio timestamp } } void setup() { Serial.begin(115200); // Serial for debug (optional) WiFi.mode(WIFI_STA); // Station mode only WiFi.disconnect(); delay(100); // --- Print this board's MAC address for pairing/debug --- Serial.print("My MAC address: "); Serial.println(WiFi.macAddress()); // ESP-NOW initialization if (esp_now_init() != ESP_OK) { Serial.println("ESP-NOW init failed!"); while (true); } // Peer setup (MAC of the other board) esp_now_del_peer(peer_mac); // Remove in case it exists esp_now_peer_info_t peerInfo; memset(&peerInfo, 0, sizeof(peerInfo)); memcpy(peerInfo.peer_addr, peer_mac, 6); peerInfo.channel = 0; peerInfo.encrypt = false; peerInfo.ifidx = WIFI_IF_STA; if (esp_now_add_peer(&peerInfo) != ESP_OK) { Serial.println("Adding peer failed!"); while (true); } // Register packet receive handler esp_now_register_recv_cb(onReceive); // Pin setup pinMode(PTT_PIN, INPUT_PULLUP); // Button: HIGH when not pressed, LOW when pressed pinMode(LED_PIN, OUTPUT); pinMode(POT_PIN, INPUT); // Potentiometer for pitch control pinMode(AMP_SHUTDOWN_PIN, OUTPUT); digitalWrite(LED_PIN, LOW); // LED OFF at startup digitalWrite(AMP_SHUTDOWN_PIN, LOW); // Amp OFF at startup // NeoPixel initialization micRing.begin(); micRing.show(); // all LEDs off rxRing.begin(); rxRing.show(); // all LEDs off Serial.println("ROBUSTRingPhone ready!"); } void loop() { static int silentMid = 1350; // Value for silence (use Serial plotter to find) static double gain = 0.0075; // Lower for loud mic, higher for weak mic // === SENDING: If PTT button is pressed, sample and transmit audio === if (digitalRead(PTT_PIN) == HIGH) { // HIGH means button is pressed! int maxMic = 0; int minMic = 4095; for (int i = 0; i < AUDIO_BLOCK; i++) { int raw = analogRead(MIC_PIN); // Microphone ADC reading int signal = abs(raw - silentMid); // Distance from silence if (raw > maxMic) maxMic = raw; if (raw < minMic) minMic = raw; int val = (raw - silentMid) * gain + 127; if (signal < noiseThreshold) { val = 127; } if (val < 0) val = 0; if (val > 255) val = 255; audioBlock[i] = val; delayMicroseconds(125); // 8kHz sample rate } esp_now_send(peer_mac, audioBlock, AUDIO_BLOCK); // Transmit audio int micLoudness = maxMic - minMic; showVUMeter(micRing, NEOPIX_MIC_NUM, micLoudness, 2000, 0.18); // 0.18 = dimmer rxRing.clear(); rxRing.show(); } else { micRing.clear(); micRing.show(); rxRing.clear(); rxRing.show(); } // === RECEIVING: If a new audio block is available and PTT NOT pressed, play it back === if (newBlock && digitalRead(PTT_PIN) == LOW) { digitalWrite(LED_PIN, HIGH); digitalWrite(AMP_SHUTDOWN_PIN, HIGH); // Enable amplifier for playback delay(1); portENTER_CRITICAL(&mux); newBlock = false; portEXIT_CRITICAL(&mux); int potVal = analogRead(POT_PIN); // 0...4095 int playbackDelay = map(potVal, 0, 4095, 90, 220); int maxRx = 0; int minRx = 255; for (int i = 0; i < AUDIO_BLOCK; i++) { if (rxBlock[i] > maxRx) maxRx = rxBlock[i]; if (rxBlock[i] < minRx) minRx = rxBlock[i]; } int rxLoudness = maxRx - minRx; showVUMeter(rxRing, NEOPIX_RX_NUM, rxLoudness, 20, 0.14); for (int i = 0; i < AUDIO_BLOCK; i++) { dacWrite(SPEAKER_PIN, rxBlock[i]); delayMicroseconds(playbackDelay); } lastAudioTime = millis(); // Update last audio timestamp digitalWrite(LED_PIN, LOW); } // --- Amp shutdown logic: turn amp OFF after timeout with no audio received --- if (digitalRead(AMP_SHUTDOWN_PIN) == HIGH && (millis() - lastAudioTime > ampTimeout)) { digitalWrite(AMP_SHUTDOWN_PIN, LOW); // Mute amp if no audio recently } } /* ----------------------------------------- Hardware wiring and project notes: ----------------------------------------- - MIC_PIN (GPIO32): Connect OUT of your microphone amplifier (e.g., MAX9814, MAX4466). - SPEAKER_PIN (GPIO25): Connect to audio amp (e.g., PAM8302A IN+). - LED_PIN (GPIO23): Anode (long leg) of LED to pin, cathode via resistor (e.g., 220Ω) to GND. - PTT_PIN (GPIO34): One side of pushbutton to this pin, other side to GND. - POT_PIN (GPIO35): Center of a 10k linear potentiometer to this pin, ends to 3.3V and GND. - AMP_SHUTDOWN_PIN (GPIO21): Connect to SHDN pin of PAM8302A. HIGH = ON, LOW = OFF. - NEOPIX_MIC_PIN (GPIO19): Data in for **24-LED NeoPixel ring** (VU meter for microphone, GRB/RGB). - NEOPIX_RX_PIN (GPIO18): Data in for **12-LED NeoPixel ring** (VU meter for received audio, GRBW/RGBW). - Both ESP32s must use this code, but each with the other's MAC in peer_mac[]. - Only one person can transmit at a time (real walkie-talkie behavior). - "Pitch control": Turn potentiometer to change voice pitch of received audio in real time. - "VU meter": Rings show audio loudness bar & color gradient in real time. - Tune gain, silentMid, noiseThreshold, and VU meter scaling for best audio with your parts! */