DRAFT lora

Author: pschatzmann

src/AudioTools/Communication/AudioLoRa.h

@@ -0,0 +1,135 @@
+#include "AudioTools/CoreAudio/Buffers.h"
+#include "LoRa.h"
+
+// define the default pins used by the transceiver module
+#define ss 8
+#define rst 12
+#define dio0 14
+
+namespace audio_tools {
+
+/**
+ * @brief LoRa Audio Configuration with default values maximised for
+ * speed.
+ * @author Phil Schatzmann
+ * @copyright GPLv3
+
+    Heltec LoRa 32 Lora Pins:
+        NSS: 8
+        SCK: 9
+        MOSI: 10
+        MISO: 11
+        RST: 12
+        BUSY: 13
+        DIO1: 14
+
+ */
+
+struct AudioLoRaConfig : public AudioInfo {
+  int32_t spi_speed = 8E6;
+  int max_size = 200;
+  int frequency = 868E6;  // (433E6, 868E6, 915E6)
+  int sync_word = 0xF3;
+  int tx_power = 20;          // 2-20;
+  int spreading_factor = 12;  // 6-12
+  int signal_bandwidth =
+      7.8E3;  // 7.8E3, 10.4E3, 15.6E3, 20.8E3, 31.25E3, 41.7E3,
+              // 62.5E3, 125E3, 250E3, and 500E3.
+  int pin_ss = ss;
+  int pin_rst = rst;
+  int pin_dio0 = dio0;
+  bool process_audio_info = true;
+};
+
+/**
+ * @brief LoRa Audio Sending and Receiving
+ * @author Phil Schatzmann
+ * @copyright GPLv3
+ */
+class AudioLoRa : public AudioStream {
+ public:
+  AudioLoRaConfig defaultConfig() {
+    AudioLoRaConfig rc;
+    return rc;
+  }
+
+  void setAudioInfo(AudioInfo info) {
+    cfg.sample_rate = info.sample_rate;
+    cfg.channels = info.channels;
+    cfg.bits_per_sample = info.bits_per_sample;
+    AudioStream::setAudioInfo(info);
+  }
+
+  bool begin(AudioLoRaConfig config) {
+    cfg = config;
+    AudioStream::setAudioInfo(config);
+    return begin();
+  }
+
+  bool begin() {
+    TRACEI();
+    buffer.resize(cfg.max_size);
+    LoRa.setSignalBandwidth(cfg.signal_bandwidth);
+    LoRa.setSpreadingFactor(cfg.spreading_factor);
+    LoRa.setTxPower(cfg.tx_power);
+    LoRa.setSPIFrequency(cfg.spi_speed);
+    LoRa.setPins(cfg.pin_ss, cfg.pin_rst, cfg.pin_dio0);
+    LoRa.setSyncWord(cfg.sync_word);
+    bool rc = LoRa.begin(cfg.frequency);
+    if (cfg.process_audio_info) {
+      writeAudioInfo();
+    }
+    return rc;
+  }
+
+  void end() { LoRa.end(); }
+
+  size_t readBytes(uint8_t* data, size_t len) {
+    TRACEI();
+    size_t packetSize = LoRa.parsePacket();
+    if (cfg.process_audio_info && packetSize == sizeof(AudioInfo)) {
+      readAudioInfo();
+      packetSize = LoRa.parsePacket();
+    }
+    int toRead = min(len, packetSize);
+    int read = LoRa.readBytes(data, toRead);
+    return read;
+  }
+
+  int available() { return cfg.max_size; }
+
+  int availableForWrite() { return cfg.max_size; }
+
+  size_t write(const uint8_t* data, size_t len) {
+    TRACEI();
+    for (int j = 0; j < len; j++) {
+      buffer.write(data[j]);
+      if (buffer.isFull()) {
+        LoRa.beginPacket();
+        LoRa.write(buffer.data(), buffer.available());
+        LoRa.endPacket();
+        buffer.clear();
+      }
+    }
+    return len;
+  }
+
+ protected:
+  AudioLoRaConfig cfg;
+  SingleBuffer<uint8_t> buffer;
+
+  void readAudioInfo() {
+    AudioInfo tmp;
+    int read = LoRa.readBytes((uint8_t*)&tmp, sizeof(AudioInfo));
+    setAudioInfo(tmp);
+  }
+
+  void writeAudioInfo() {
+    LoRa.beginPacket();
+    AudioInfo ai = audioInfo();
+    LoRa.write((uint8_t*)&ai, sizeof(ai));
+    LoRa.endPacket();
+  }
+};
+
+}  // namespace audio_tools

src/AudioTools/CoreAudio/AudioStreams.h

@@ -752,6 +752,7 @@ class MeasuringStream : public ModifyingStream {
       return true;
     }
 
+    /// Trigger reporting in frames (=samples) per second
     void setFrameSize(int size){
       frame_size = size;
     }